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Discussion Starter · #1 · (Edited)
How many here match prep there rifle cartridge cases ?

I do the full match prep with first full length sizing with a conventional die with the pull trough neck sizing button, but lube the outside of the case body and inside of the case neck with RCBS Case Lube 2. Lubing the inside of the case neck helps by not stretching the case neck and from galling the brass.

As for neck turning first using a RCBS Case Trimmer 2 for the ruff turn with a drill attached to the shaft and use Tap Magic non ferrous metal cutting fluid to lubricate the pilot and for the outside neck cutting, then finish turn with a K&M hand tool of which that is between .001”-.002”. I trim the necks with a Forster as it has only .0004” runout. I use 90 weight gear lube on the shafts of both the RCBS and Forster tools as lubrication, and it also dampens the shafts. I also make my own pilots for the RCBS and Forster. For the case neck inside chamfer I used a Redding 15° tool and outside a RCBS tool that I chuck into drill set on slow. Then I polish the chamfers with a tool made from a 1/2” socket with a hex shaft with a wad of 0000 steel wool in it held in place with a patch of Velcro hook. This polishing of the case mouth alleviates any bullet jacket scoring/shaving when seating the bullets. The main reason for case neck turning is that case neck tension is more consistent, and a more concentric release of the bullet in relation to the barrels bore. Case neck trimming mite have to be done periodically as case necks grow in length from brass flow, or if a conventional pull through neck sizing button is used regardless of lubricating the inside of the case neck. If anyone would like to see my DIY case mouth polishing tool, I’ll post an image of it.

I been using a RCBS Primer Pocket Uniforming tool chucked in a drill on low speed for squaring the primer pocket and creating a consistent depth that I modified to be able to adjust the depth of cut. I also use the Tap Magic cutting fluid for cutting the primer pockets for the original cut. This lubricates the cutting and also lubricates the case head to mitigate galling. The original cutting is done usually with two to four cutting as the cutter will load up with brass shaving to which I use a tooth brush to clean the shavings of the cutter. Plus doing the original cut in several cuts reduces the possibility of chatter. After the first primer depth cutting, I’ll reuse the the tool to clean out primer residue and if a high pressure load is the node the cartridge/firearm is most accurate at mite compress the brass case head and reduce the primer pocket depth by anywhere from .001-.0015”. This is important in maintaining the same firing pin travel and primer hight. How much the bass case head/primer pocket will compress is dependent on the brand of cases, and some times the particular lot, as some brands the copper zinc alloying can vary, or how high a pressure the cartridge is loaded to. After the primer pocket has been depth cut, I use a #1 center drill hand turned to cut a very slight chamfer to the primer pocket flash hole. If anyone would see my modified tool, I’ll post an image of it and how I modified it.

The inside of flash hole in the case I been using a RCBS flash hole deburring tool I modified by using a short piece of 1/8” brass tube that depth of cut is adjustable by the tube stopping against the tools pilot, but the pilot tool doesn’t stop against the case mouth so the tool isn’t dependent on the case neck length. Most primer flash holes are punched from the outside of the case which creates a burr inside the case. Using my method removes the burr and only cuts a very slight chamfer to the flash hole. K&M makes a inside flash hole deburring tool that incorporates a depth stop, but I found the floating pilot to be difficult to be positively centered in the case mouth. This operation is needed to be done once as subsequent firings will not affect it. If anyone would like to see my modified tool, I’ll post an image of it.

After all this prep work is done, I’ll run the cases in a vibratory case polisher with new corn cob for an hour or so to clean out and off all the various lubricants I used.

As for resizing the fired cases, I use Redding bushing neck dies, be it just neck or full length resizing. These types of dies although are more expensive then a more conventional resizing die with a pull through neck sizing button, the neck bushing will not stretch the brass neck or over work the brass which because of the copper in the brass alloy can be work harden, which will affect case neck tension which affect accuracy. Plus a pull through type of neck sizing button can stretch the case neck and create case neck runout. The only caveat in using neck bushing dies, is that they are most beneficial if the case necks have been turn to a consistent thickness. If the case necks are not turned, then a conventional resizing die with a neck sizing button is more suitable.

I would go into case neck annealing, but that is a science in of itself that if done improperly will adversely affect accuracy or even ruin the cases and possibly causing damage to the firearm, or more importantly the shooter.

Now the truth is that for each case it takes about ten or so minutes to perform all of these operations. I know this is more time then most would want to spend working on one case at a time, but if the particular rifle will shoot 1/2” or less groups, the accuracy potential can only be increased by full match prepping. I actually take it one step further by full match prepping more cartridge cases then I’ll want by weighing and segregating by weight. This will assure me that volume of the cases are as close as possible to all being the same. The reason this important is if the volume of the individual cases varies, the chamber pressure will vary with each case. If the volume of each case is the same, then the chamber pressure will as close to the same, and the barrel harmonics will be as close to the same from shot to shot, and that is one of the important aspects to obtaining an accurate load for a rifle, finding that node where the barrel is happy and humming the same tune.

Just to clarify, I do not compete in Benchrest, or F-Class, but I am obsessed with accuracy which paid off when I used to compete in IHMSA competition, and helped me win many matches in the Unlimited Class. If any Benchrest, F-Class, or PRS shooters have anything to add to this, feel free.
 

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Discussion Starter · #3 ·
Here is the tools I referred to that I’ve modified.

This the tool I use to polish the case mouth edge after I do the inside/outside chamfer. In this case I using a 13mm drive socket (about $2.00-$3.00) i, but if a larger case is being worked, use a larger socket. The steel wool in this one has been used on about 50 cases. After that many, I’ll pull the steel wool out and reposition it. Each tuft of steel wool good for about 200 cases. Like I stated in my previous write up, I have a disc of Velcro hook in the bottom of the socket well to hold tge steel wool from grabbing the case mouth edge and spinning in the socket well. The Velcro has a self adhesive back. This type of Velcro can be found at some hardware stores, or order it on line. Just make sure it has a self adhesive backing. I should mention that I saw this ifea from another gun forum, so I’m not claiming any credit for it.
Automotive lighting Auto part Metal Fashion accessory Circle


This is the modified RCBS Primer Pocket Uniform ing tool. What I did was heat the blacked steel cutter holder to break the bond of the tread lock from the factory. Loosen the set screw, and with pliers with a strip of leather in the jaws grab the side of the carbide cutter and carefully pull the cutter out. I stress that this is done with care as carbide does chip somewhat easily. Once the cutter is removed the 10-24 threaded shaft mite need heat to break the bond of thread lock to back it out. There is a hex socket well on the exposed end that screw where a key screw wrench will fit into for removal. Once the threaded shaft is out, use a #29/.136” (about $2.00 from a hardware store) drill bit to dill completely through the treaded hole in the cutter holder. Use a 8-32 tap (about $3.00-$5.00 at a hardware store) to finish cutting the threads all the way through and out of the socket the cutter sets in. Reassemble the cutter and set screw. Set the depth of the cutter with a caliper, and lock the side set screw and the 8-32 nut on the threaded shaft.
Household hardware Nickel Gas Cylinder Auto part

Product Liquid Fluid Material property Gas

This a SAAMI spec chart of primer pocket depths.
Rectangle Product Slope Font Parallel


Here is the RCBS Internal Primer Flash Hole Deburring Tool that only modification is the 1/8” I.D. brass tube (about $5.00 for a12” tube at most hardware stores) slipped over the cutters shaft. The particular pilot shown is a 25 caliber, but I have pilots in other calibers. The various lengths of brass tube are several cartridges with the longest one shown is for any cartridge case based on the 308 Win. The two shorter examples are for 22-250 and 223 Rem. The operation is to cut the length of brass tube with a small plumbing wheeled metal tubing cutter (about $5.00) so when the depth of cut in the flash hole has the pilot only entering the case mouth to about 2/3rds to 3/4trs of its length. Tighten the set screw (not shown) between the two knurlings. After the flash hole has been deburred, remove the tool from the case and slide the brass forth and back to loosen the flash hole burr shaving out to clear the cutter for the next cartridge.
Product Office supplies Font Material property Wood

This last image illustrates the amount of extension the cutter needed to be. Only the flash hole burr and a slight chamfer is needed to be removed from inside the cartridge case.
Wood Tints and shades Beige Metal Rectangle
 

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I guess I take a lot of short cuts…….
 

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I went down a similar rabbit hole. Tried to make everything perfect. Bone stock off the rack rig may or may not compete well with a custom. I went through numerous TC barrels and tinkering with XP’s when I was hard core in IHMSA. Loved SW, never could get it to shoot worth a decent score. An FA 353 arrived, a little work. First score was a 39x40,numerous 40x40 after that, actually used it for a “P” gun as well.

I honestly believe tinkering with things we believe make a rig shoot better is more a confidence booster than anything.
I have not cleaned a primer pocket in years.
I never neck turn unless it is spec’d that way.

My F class rifle sees little more than what I do for my varmint rifles. Lol, others shoot my rifle better than I do

Out of the dozen varmint rifles I have from 17-6mm, all satisfy my needs and shoot well at distances I use them at.
 

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Years ago, when I shot High Power Rifle, I learned quickly that I needed to deburr the flash hole and to use quality match bullets like Sierra or Hornady. Those two things dropped my group size to about 1/4 to 1/3 the former size. I do set up my dies and do watch OAL and trimming as the brass grows. I do segregate my brass to the rifle and don't mix brass between rifles, and NS only for my bolt guns, until I finally need to set back a shoulder. Don't shoot BR, and never got into neck turning.
 

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I basically do all the case prep except for neck turning. I have found the case prep does make a difference and is worthwhile doing. I hardly ever neck size anymore, I do with virgin brass for the 1st loading and then I bump the shoulder back .001 on my brass with FL sizing die each loading.
 

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Nice detailed write up PRR.

Before I load a case I trim it to length, deburr both the inside and outside, deburr the flash hole and uniform the primer pocket. I also remove any primer crimp. I only neck turn for my tight neck rifles. I also only neck size for those rifles. Everything else gets full length sized. I have carbide expander balls for the calibers that I load the most. I seat he primers with a Sinclair hand priming tool. Most of my case prep tools are Wilson, Sinclair or K&M.

Varmint Al discussed using a nut driver with steel wool to polish the case mouth but I've never done it. His web site is interesting and worth a look.
 

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If you look at your necks with a 12x loupe you will see just how important the steel wool spinner is. I made mine out of copper pipe caps like Varmint Al after reading his website. It makes a big difference..
 

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I have a routine that I follow for each cartridge / rifle. Some of the steps are common, but not all. Coming back from the range, the first thing I do is run the casings through a DeCap Die (RCBS). Then I run them through a tumbler to get them nice and clean. Then I neck / full length resize without the decapping rod and expander (RCBS / Redding / Lee). I use a separate neck mandrel die to expand the neck .001 - I use a graphite powder on the neck during this operation (LE Wilson). I verify case length and trim, chamfer and debur. I only clean the primer pocket because when the cases are new I uniform the primer pocket and flash hole then. I keep all of my brass in lots and I leave a punch list of the steps that I have taken...just because, I get interrupted and then can't remember what and where I was in the process. I generally don't neck turn - do on occasion Inside Neck Ream (LE Wilson). Only when I find evidence that the neck isn't cleanly releasing. I drop an unfired projectile down the case necks to check this. It still takes hours from start to finish. In the future, I want to get to adding annealing into the process...but that can be expensive and I have to set aside dedicated space (I don't want fire anywhere near powder, primers or load benches). My OCD level climbs when handloading my heavy barrels...
 

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How many here match prep there rifle cartridge cases ?

I do the full match prep with first full length sizing with a conventional die with the pull trough neck sizing button, but lube the outside of the case body and inside of the case neck with RCBS Case Lube 2. Lubing the inside of the case neck helps by not stretching the case neck and from galling the brass.

As for neck turning first using a RCBS Case Trimmer 2 for the ruff turn with a drill attached to the shaft and use Tap Magic non ferrous metal cutting fluid to lubricate the pilot and for the outside neck cutting, then finish turn with a K&M hand tool of which that is between .001”-.002”. I trim the necks with a Forster as it has only .0004” runout. I use 90 weight gear lube on the shafts of both the RCBS and Forster tools as lubrication, and it also dampens the shafts. I also make my own pilots for the RCBS and Forster. For the case neck inside chamfer I used a Redding 15° tool and outside a RCBS tool that I chuck into drill set on slow. Then I polish the chamfers with a tool made from a 1/2” socket with a hex shaft with a wad of 0000 steel wool in it held in place with a patch of Velcro hook. This polishing of the case mouth alleviates any bullet jacket scoring/shaving when seating the bullets. The main reason for case neck turning is that case neck tension is more consistent, and a more concentric release of the bullet in relation to the barrels bore. Case neck trimming mite have to be done periodically as case necks grow in length from brass flow, or if a conventional pull through neck sizing button is used regardless of lubricating the inside of the case neck. If anyone would like to see my DIY case mouth polishing tool, I’ll post an image of it.

I been using a RCBS Primer Pocket Uniforming tool chucked in a drill on low speed for squaring the primer pocket and creating a consistent depth that I modified to be able to adjust the depth of cut. I also use the Tap Magic cutting fluid for cutting the primer pockets for the original cut. This lubricates the cutting and also lubricates the case head to mitigate galling. The original cutting is done usually with two to four cutting as the cutter will load up with brass shaving to which I use a tooth brush to clean the shavings of the cutter. Plus doing the original cut in several cuts reduces the possibility of chatter. After the first primer depth cutting, I’ll reuse the the tool to clean out primer residue and if a high pressure load is the node the cartridge/firearm is most accurate at mite compress the brass case head and reduce the primer pocket depth by anywhere from .001-.0015”. This is important in maintaining the same firing pin travel and primer hight. How much the bass case head/primer pocket will compress is dependent on the brand of cases, and some times the particular lot, as some brands the copper zinc alloying can vary, or how high a pressure the cartridge is loaded to. After the primer pocket has been depth cut, I use a #1 center drill hand turned to cut a very slight chamfer to the primer pocket flash hole. If anyone would see my modified tool, I’ll post an image of it and how I modified it.

The inside of flash hole in the case I been using a RCBS flash hole deburring tool I modified by using a short piece of 1/8” brass tube that depth of cut is adjustable by the tube stopping against the tools pilot, but the pilot tool doesn’t stop against the case mouth so the tool isn’t dependent on the case neck length. Most primer flash holes are punched from the outside of the case which creates a burr inside the case. Using my method removes the burr and only cuts a very slight chamfer to the flash hole. K&M makes a inside flash hole deburring tool that incorporates a depth stop, but I found the floating pilot to be difficult to be positively centered in the case mouth. This operation is needed to be done once as subsequent firings will not affect it. If anyone would like to see my modified tool, I’ll post an image of it.

After all this prep work is done, I’ll run the cases in a vibratory case polisher with new corn cob for an hour or so to clean out and off all the various lubricants I used.

As for resizing the fired cases, I use Redding bushing neck dies, be it just neck or full length resizing. These types of dies although are more expensive then a more conventional resizing die with a pull through neck sizing button, the neck bushing will not stretch the brass neck or over work the brass which because of the copper in the brass alloy can be work harden, which will affect case neck tension which affect accuracy. Plus a pull through type of neck sizing button can stretch the case neck and create case neck runout. The only caveat in using neck bushing dies, is that they are most beneficial if the case necks have been turn to a consistent thickness. If the case necks are turned, then a conventional resizing die with a neck sizing button is more suitable.

I would go into case neck annealing, but that is a science in of itself that if done improperly will adversely affect accuracy or even ruin the cases and possibly causing damage to the firearm, or more importantly the shooter.

Now the truth is that for each case it takes about ten or so minutes to perform all of these operations. I know this is more time then most would want to spend working on one case at a time, but if the particular rifle will shoot 1/2” or less groups, the accuracy potential can only be increased by full match prepping. I actually take it one step further by full match prepping more cartridge cases then I’ll want by weighing and segregating by weight. This will assure me that volume of the cases are as close as possible to all being the same. The reason this important is if the volume of the individual cases varies, the chamber pressure will vary with each case. If the volume of eachis the same, then the chamber pressure will as close to the same, and the barrel harmonics will be as close to the same from shot to shot, and that is one of the important aspects to obtaining an accurate load for a rifle, finding that node where the barrel is happy and humming the same tune.

Just to clarify, I do not compete in Benchrest, or F-Class, but I am obsessed with accuracy which paid off when I used to compete in IHMSA competition, and helped me win many matches in the Unlimited Class. If any Benchrest, F-Class, or PRS shooters have anything to add to this, feel free.
I do most of the steps. One think I didn't see you discuss is matching the case length to the 0.001", and weighing bullets to match them within 0.1 gr. I do this when loading testing/accuracy tests. Once the best load is developed, I'll relax the standards a little bit.
 

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Eric Cortina has some videos that may interest some on the subject.
How many here match prep there rifle cartridge cases ?

I do the full match prep with first full length sizing with a conventional die with the pull trough neck sizing button, but lube the outside of the case body and inside of the case neck with RCBS Case Lube 2. Lubing the inside of the case neck helps by not stretching the case neck and from galling the brass.

As for neck turning first using a RCBS Case Trimmer 2 for the ruff turn with a drill attached to the shaft and use Tap Magic non ferrous metal cutting fluid to lubricate the pilot and for the outside neck cutting, then finish turn with a K&M hand tool of which that is between .001”-.002”. I trim the necks with a Forster as it has only .0004” runout. I use 90 weight gear lube on the shafts of both the RCBS and Forster tools as lubrication, and it also dampens the shafts. I also make my own pilots for the RCBS and Forster. For the case neck inside chamfer I used a Redding 15° tool and outside a RCBS tool that I chuck into drill set on slow. Then I polish the chamfers with a tool made from a 1/2” socket with a hex shaft with a wad of 0000 steel wool in it held in place with a patch of Velcro hook. This polishing of the case mouth alleviates any bullet jacket scoring/shaving when seating the bullets. The main reason for case neck turning is that case neck tension is more consistent, and a more concentric release of the bullet in relation to the barrels bore. Case neck trimming mite have to be done periodically as case necks grow in length from brass flow, or if a conventional pull through neck sizing button is used regardless of lubricating the inside of the case neck. If anyone would like to see my DIY case mouth polishing tool, I’ll post an image of it.

I been using a RCBS Primer Pocket Uniforming tool chucked in a drill on low speed for squaring the primer pocket and creating a consistent depth that I modified to be able to adjust the depth of cut. I also use the Tap Magic cutting fluid for cutting the primer pockets for the original cut. This lubricates the cutting and also lubricates the case head to mitigate galling. The original cutting is done usually with two to four cutting as the cutter will load up with brass shaving to which I use a tooth brush to clean the shavings of the cutter. Plus doing the original cut in several cuts reduces the possibility of chatter. After the first primer depth cutting, I’ll reuse the the tool to clean out primer residue and if a high pressure load is the node the cartridge/firearm is most accurate at mite compress the brass case head and reduce the primer pocket depth by anywhere from .001-.0015”. This is important in maintaining the same firing pin travel and primer hight. How much the bass case head/primer pocket will compress is dependent on the brand of cases, and some times the particular lot, as some brands the copper zinc alloying can vary, or how high a pressure the cartridge is loaded to. After the primer pocket has been depth cut, I use a #1 center drill hand turned to cut a very slight chamfer to the primer pocket flash hole. If anyone would see my modified tool, I’ll post an image of it and how I modified it.

The inside of flash hole in the case I been using a RCBS flash hole deburring tool I modified by using a short piece of 1/8” brass tube that depth of cut is adjustable by the tube stopping against the tools pilot, but the pilot tool doesn’t stop against the case mouth so the tool isn’t dependent on the case neck length. Most primer flash holes are punched from the outside of the case which creates a burr inside the case. Using my method removes the burr and only cuts a very slight chamfer to the flash hole. K&M makes a inside flash hole deburring tool that incorporates a depth stop, but I found the floating pilot to be difficult to be positively centered in the case mouth. This operation is needed to be done once as subsequent firings will not affect it. If anyone would like to see my modified tool, I’ll post an image of it.

After all this prep work is done, I’ll run the cases in a vibratory case polisher with new corn cob for an hour or so to clean out and off all the various lubricants I used.

As for resizing the fired cases, I use Redding bushing neck dies, be it just neck or full length resizing. These types of dies although are more expensive then a more conventional resizing die with a pull through neck sizing button, the neck bushing will not stretch the brass neck or over work the brass which because of the copper in the brass alloy can be work harden, which will affect case neck tension which affect accuracy. Plus a pull through type of neck sizing button can stretch the case neck and create case neck runout. The only caveat in using neck bushing dies, is that they are most beneficial if the case necks have been turn to a consistent thickness. If the case necks are turned, then a conventional resizing die with a neck sizing button is more suitable.

I would go into case neck annealing, but that is a science in of itself that if done improperly will adversely affect accuracy or even ruin the cases and possibly causing damage to the firearm, or more importantly the shooter.

Now the truth is that for each case it takes about ten or so minutes to perform all of these operations. I know this is more time then most would want to spend working on one case at a time, but if the particular rifle will shoot 1/2” or less groups, the accuracy potential can only be increased by full match prepping. I actually take it one step further by full match prepping more cartridge cases then I’ll want by weighing and segregating by weight. This will assure me that volume of the cases are as close as possible to all being the same. The reason this important is if the volume of the individual cases varies, the chamber pressure will vary with each case. If the volume of each case is the same, then the chamber pressure will as close to the same, and the barrel harmonics will be as close to the same from shot to shot, and that is one of the important aspects to obtaining an accurate load for a rifle, finding that node where the barrel is happy and humming the same tune.

Just to clarify, I do not compete in Benchrest, or F-Class, but I am obsessed with accuracy which paid off when I used to compete in IHMSA competition, and helped me win many matches in the Unlimited Class. If any Benchrest, F-Class, or PRS shooters have anything to add to this, feel free.
Well, about all I can add is
How many here match prep there rifle cartridge cases ?

I do the full match prep with first full length sizing with a conventional die with the pull trough neck sizing button, but lube the outside of the case body and inside of the case neck with RCBS Case Lube 2. Lubing the inside of the case neck helps by not stretching the case neck and from galling the brass.

As for neck turning first using a RCBS Case Trimmer 2 for the ruff turn with a drill attached to the shaft and use Tap Magic non ferrous metal cutting fluid to lubricate the pilot and for the outside neck cutting, then finish turn with a K&M hand tool of which that is between .001”-.002”. I trim the necks with a Forster as it has only .0004” runout. I use 90 weight gear lube on the shafts of both the RCBS and Forster tools as lubrication, and it also dampens the shafts. I also make my own pilots for the RCBS and Forster. For the case neck inside chamfer I used a Redding 15° tool and outside a RCBS tool that I chuck into drill set on slow. Then I polish the chamfers with a tool made from a 1/2” socket with a hex shaft with a wad of 0000 steel wool in it held in place with a patch of Velcro hook. This polishing of the case mouth alleviates any bullet jacket scoring/shaving when seating the bullets. The main reason for case neck turning is that case neck tension is more consistent, and a more concentric release of the bullet in relation to the barrels bore. Case neck trimming mite have to be done periodically as case necks grow in length from brass flow, or if a conventional pull through neck sizing button is used regardless of lubricating the inside of the case neck. If anyone would like to see my DIY case mouth polishing tool, I’ll post an image of it.

I been using a RCBS Primer Pocket Uniforming tool chucked in a drill on low speed for squaring the primer pocket and creating a consistent depth that I modified to be able to adjust the depth of cut. I also use the Tap Magic cutting fluid for cutting the primer pockets for the original cut. This lubricates the cutting and also lubricates the case head to mitigate galling. The original cutting is done usually with two to four cutting as the cutter will load up with brass shaving to which I use a tooth brush to clean the shavings of the cutter. Plus doing the original cut in several cuts reduces the possibility of chatter. After the first primer depth cutting, I’ll reuse the the tool to clean out primer residue and if a high pressure load is the node the cartridge/firearm is most accurate at mite compress the brass case head and reduce the primer pocket depth by anywhere from .001-.0015”. This is important in maintaining the same firing pin travel and primer hight. How much the bass case head/primer pocket will compress is dependent on the brand of cases, and some times the particular lot, as some brands the copper zinc alloying can vary, or how high a pressure the cartridge is loaded to. After the primer pocket has been depth cut, I use a #1 center drill hand turned to cut a very slight chamfer to the primer pocket flash hole. If anyone would see my modified tool, I’ll post an image of it and how I modified it.

The inside of flash hole in the case I been using a RCBS flash hole deburring tool I modified by using a short piece of 1/8” brass tube that depth of cut is adjustable by the tube stopping against the tools pilot, but the pilot tool doesn’t stop against the case mouth so the tool isn’t dependent on the case neck length. Most primer flash holes are punched from the outside of the case which creates a burr inside the case. Using my method removes the burr and only cuts a very slight chamfer to the flash hole. K&M makes a inside flash hole deburring tool that incorporates a depth stop, but I found the floating pilot to be difficult to be positively centered in the case mouth. This operation is needed to be done once as subsequent firings will not affect it. If anyone would like to see my modified tool, I’ll post an image of it.

After all this prep work is done, I’ll run the cases in a vibratory case polisher with new corn cob for an hour or so to clean out and off all the various lubricants I used.

As for resizing the fired cases, I use Redding bushing neck dies, be it just neck or full length resizing. These types of dies although are more expensive then a more conventional resizing die with a pull through neck sizing button, the neck bushing will not stretch the brass neck or over work the brass which because of the copper in the brass alloy can be work harden, which will affect case neck tension which affect accuracy. Plus a pull through type of neck sizing button can stretch the case neck and create case neck runout. The only caveat in using neck bushing dies, is that they are most beneficial if the case necks have been turn to a consistent thickness. If the case necks are turned, then a conventional resizing die with a neck sizing button is more suitable.

I would go into case neck annealing, but that is a science in of itself that if done improperly will adversely affect accuracy or even ruin the cases and possibly causing damage to the firearm, or more importantly the shooter.

Now the truth is that for each case it takes about ten or so minutes to perform all of these operations. I know this is more time then most would want to spend working on one case at a time, but if the particular rifle will shoot 1/2” or less groups, the accuracy potential can only be increased by full match prepping. I actually take it one step further by full match prepping more cartridge cases then I’ll want by weighing and segregating by weight. This will assure me that volume of the cases are as close as possible to all being the same. The reason this important is if the volume of the individual cases varies, the chamber pressure will vary with each case. If the volume of each case is the same, then the chamber pressure will as close to the same, and the barrel harmonics will be as close to the same from shot to shot, and that is one of the important aspects to obtaining an accurate load for a rifle, finding that node where the barrel is happy and humming the same tune.

Just to clarify, I do not compete in Benchrest, or F-Class, but I am obsessed with accuracy which paid off when I used to compete in IHMSA competition, and helped me win many matches in the Unlimited Class. If any Benchrest, F-Class, or PRS shooters have anything to add to this, feel free.
Well, I ain't no BR competator or PRS shooter, but if shooting iddy biddy groups and what it takes to get there matters, then I'm "innerested"! (I attached a couple targets of mine, shot at 200 yards after full case prep as well as performing some other equally important chapters in precision shooting - hoping these results demonstrate some ability, satisfactory to be qualified enough to "feel free" to comment?. 😄

Far as your article (here) goes, seems like you've touched just about every important aspect of match case prep one might find in a collection of articles by renown BR shooters. Nicely done.

I think we could all agree that case to case uniformity in all respects is an ideal goal. However, the fact is that some aspects have greater affect on accuracy than others, e.g., some things might change the group size from 3/4" at 100 yards to under 3/8", and another particular item of case prep may make an improvement in group size that is impossible to determine if it was preparation OR conditions (i.e., wind, mirage, etc) that resulted in group size variation. My point is, there is a practical limit to the degree of uniformity in case prep which is defined by the curve of diminishing returns.

But, once one decides what procedures ARE important, far as case prep goes, then the focus on tooling becomes important. Tooling is important because of not only the precision achieved with good tools, but the time cut in the process(s) means one can prep more cases OR dive deeper into the fine steps that might make a minuscule improvement on target.

Case uniformity
Bullet uniformity
Powder type and lot#
Primer selection and lot#
SEATING DEPTH (in caps cuz it is a BIG factor!)
RUNOUT (also a BIG factor)
Die selection
Neck tension
Twist rate vs. bullet

For what it's worth, case uniformity is but one of the ammo prep factors that we control to the limits of our ability to measure physical variations. But, the conditions during the shot prep (mirage, wind, sun angle) and site (scope) limitations usually have more to determine group size than many of the tedious steps we can conjure far as mechanical refinements go.

But, that said, I (like many others) have evolved to using a hobby lathe to effect most all of the case prep machining in your article. And I use bushing (Wilson dies, if not custom reamed) to minimize runnout of loaded rounds. With the lathe I find I can cut my case prep time by 3/4 or more on some case types. And, starting with premium cases too goes a long way toward limiting the number of culls necessary to end up with a given number of prepped cases.

And, for the record, the 3-shot groups posted here were shot at dusk on a summer night with headlights on the paper. It had been dead calm for a couple hours, the air was cool, and zero mirage. The purpose of the test was to see what was possible under ideal conditions using most all of the techniques for the case prep part (not to mention those other factors listed) when the uncontrollable factors were minimized.

Again! Nice article. Thanks 4 posting.

P.



the 'proof is in the pudding', when it comes to what is and isn't important when it comes to case prep (in this instance)
 

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Discussion Starter · #14 ·
I went down a similar rabbit hole. Tried to make everything perfect. Bone stock off the rack rig may or may not compete well with a custom. I went through numerous TC barrels and tinkering with XP’s when I was hard core in IHMSA. Loved SW, never could get it to shoot worth a decent score. An FA 353 arrived, a little work. First score was a 39x40,numerous 40x40 after that, actually used it for a “P” gun as well.

I honestly believe tinkering with things we believe make a rig shoot better is more a confidence booster than anything.
I have not cleaned a primer pocket in years.
I never neck turn unless it is spec’d that way.

My F class rifle sees little more than what I do for my varmint rifles. Lol, others shoot my rifle better than I do

Out of the dozen varmint rifles I have from 17-6mm, all satisfy my needs and shoot well at distances I use them at.
I shot IHMSA first in Texas in 1980 first with a Ruger Super Blackhawk 10.5” barrel in 44 mag, but switched to a T/C Contender 14” in 35 Rem. Years later I used a Contender 14” in 7T/CU and tried a XP100 in 7BR Rem, but the Contender was easier to use in competition. The XP was regulated to whitetail deer hunting in Michigan.

I have been toying with getting into F-Class, but I found a gun club about an hour’s drive from home that host both F-Class and IHNSA. Ah, decision decisions.
 

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Discussion Starter · #15 ·
I do most of the steps. One think I didn't see you discuss is matching the case length to the 0.001", and weighing bullets to match them within 0.1 gr. I do this when loading testing/accuracy tests. Once the best load is developed, I'll relax the standards a little bit.
I definitely trim. I’ve been using a Forster case trimmer. With some of my cartridges I do ruff neck turn/cut, first with a RCBS Case Trimmer 2 (with the collet clamp), then finish turn/cut .001”-.002”clean up with a K&M hand tool with a selection of their carbide cutters that have the cutters that match the cartridge case shoulder angle.
 

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Discussion Starter · #16 ·
Eric Cortina has some videos that may interest some on the subject.
Yep. I watch his videos too. Also. There is a very good video with David Tubb produced by Sierra where Tubb shows his methods of cartridge case prep. I learned one new this was the banana effect on the case body. The video is about 45 minutes long, but definitely worth watching. I also like on YouTube, Johnny’s Reloading Bench for gunpowders evaluations.
 

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Discussion Starter · #17 ·
Well, about all I can add is


Well, I ain't no BR competator or PRS shooter, but if shooting iddy biddy groups and what it takes to get there matters, then I'm "innerested"! (I attached a couple targets of mine, shot at 200 yards after full case prep as well as performing some other equally important chapters in precision shooting - hoping these results demonstrate some ability, satisfactory to be qualified enough to "feel free" to comment?. 😄

Far as your article (here) goes, seems like you've touched just about every important aspect of match case prep one might find in a collection of articles by renown BR shooters. Nicely done.

I think we could all agree that case to case uniformity in all respects is an ideal goal. However, the fact is that some aspects have greater affect on accuracy than others, e.g., some things might change the group size from 3/4" at 100 yards to under 3/8", and another particular item of case prep may make an improvement in group size that is impossible to determine if it was preparation OR conditions (i.e., wind, mirage, etc) that resulted in group size variation. My point is, there is a practical limit to the degree of uniformity in case prep which is defined by the curve of diminishing returns.

But, once one decides what procedures ARE important, far as case prep goes, then the focus on tooling becomes important. Tooling is important because of not only the precision achieved with good tools, but the time cut in the process(s) means one can prep more cases OR dive deeper into the fine steps that might make a minuscule improvement on target.

Case uniformity
Bullet uniformity
Powder type and lot#
Primer selection and lot#
SEATING DEPTH (in caps cuz it is a BIG factor!)
RUNOUT (also a BIG factor)
Die selection
Neck tension
Twist rate vs. bullet

For what it's worth, case uniformity is but one of the ammo prep factors that we control to the limits of our ability to measure physical variations. But, the conditions during the shot prep (mirage, wind, sun angle) and site (scope) limitations usually have more to determine group size than many of the tedious steps we can conjure far as mechanical refinements go.

But, that said, I (like many others) have evolved to using a hobby lathe to effect most all of the case prep machining in your article. And I use bushing (Wilson dies, if not custom reamed) to minimize runnout of loaded rounds. With the lathe I find I can cut my case prep time by 3/4 or more on some case types. And, starting with premium cases too goes a long way toward limiting the number of culls necessary to end up with a given number of prepped cases.

And, for the record, the 3-shot groups posted here were shot at dusk on a summer night with headlights on the paper. It had been dead calm for a couple hours, the air was cool, and zero mirage. The purpose of the test was to see what was possible under ideal conditions using most all of the techniques for the case prep part (not to mention those other factors listed) when the uncontrollable factors were minimized.

Again! Nice article. Thanks 4 posting.

P.



the 'proof is in the pudding', when it comes to what is and isn't important when it comes to case prep (in this instance)
Aside from all of what I do for a full match cartridge case prep, the last thing I’ll do is weigh each cartridge case and segregate by weight, with selecting the case that all weighed within .1 of a grain. This assures me that all the cartridge cases have the same internal volume, at least in theory. The problem is that sometimes time I’ll have to full match prep 500 cartridge cases to hopefully get 100 or more identical cases. Though when I use Lapua or Peterson Select cartridge cases, weights are usually with .1-.2 of a grain to start with.
 

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Aside from all of what I do for a full match cartridge case prep, the last thing I’ll do is weigh each cartridge case and segregate by weight, with selecting the case that all weighed within .1 of a grain. This assures me that all the cartridge cases have the same internal volume, at least in theory. The problem is that sometimes time I’ll have to full match prep 500 cartridge cases to hopefully get 100 or more identical cases. Though when I use Lapua or Peterson Select cartridge cases, weights are usually with .1-.2 of a grain to start with.
Yup. Totally agree w/ the weight step. Once the exterior of the case is massaged into compliance, then weight is what assures the internal stuff is also uniform - to a large degree - we hope!

Good discussion. I enjoyed it. The challenge left is methods of achieving the exterior dimensions - i.e., the machining (that is).
 

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Wow! You all do put a lot of effort into your case prep. That being said I do the same because I shoot benchrest. Here are a couple of additions I have. When turning cases it seems to work best if there is .002" clearance between the loaded round neck and the chamber (.001" on each side). Anything tighter and shots seem to go astray. Always use wind flags when testing loads. Almost all benchrest shooters FLR their cases using bushing dies or custom made one piece dies. All use glue in or pillar bedded actions and all barrels are free floated. Cases are important for accuracy but bullets and barrels are more so. If you can, load at the range. This gives you best ability to get change your loads for the best accuracy with the least amount of work and time. Most importantly buy Tony Boyer's book The Book of Rifle Accuracy and read it. It is the best book on rifle accuracy written.
 
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