[robbor]

Im a little confused. I have read a thread or two on crowning but all are different some of the tools leave me with questions.
The first article they used a hand reamer(from midway/brownells) that reamed the 11 deg crown and I want to say that was all they did.
Now I have seen the same type of piloted reamer that is basically a 9odeg piloted countersinkcalled a 45), is this needed? I notice that on most factory crowns they do look countersunk just a hair.

Next is laps, I have seen 2 styles, one with a round ball on the end and a cone shaped portion that i would guess is there the lapping takes place. They the other style is just a straight lap with a handle, but I dont see any surface to lap the crown. Is there any pictoral tutorials on lapping a crown? Also midways info on the laps say to ocsilate not rotate/spin. I was thinking if trying to lap a crown with one of the ball type laps on a flex shaft with a drillso the lap would stap centered and lap the crown equally, is this not correct?

 

[Gary in NH]

A couple of years ago I recrowned an old 22 bolt action Savage. I bought my tools from Brownells after e-mailing them asking for recommendations. I found the process to be easy to do as long as you have patience. I forget the names of the tools but used a facing tool which ground the muzzle flat and at right angles to the barrel. I then used a crowning tool which was a recessed 11° crown when finished. The barrel turned out nicely and shoots better than it ever had. Give Brownells a call and I am sure their tech people can help you out for your particular project.

 

[Sam in Va.]

basic crowning I do

This is by NO MEANS the best way,but I do it on all of my guns and it works.
First I inspect the crown with a loupe or magnifying glass to see what I want to fix. Then I use a high quality stainless 5/16"- 3/8"steel ball bearings(available from Macmaster Carr & other places google search stainless steel ball bearings)to touch up a 22-6mm crown. Put a little JB bore cleaner on the ball or crown and turn it 25-50 times 1 way, and 25- 50 the other with moderate pressure, occassionally rotating the ball orbitally. Inspect the cutting progress with a glass,clean out the JB from the bore and go shooting. You can also use a drill, run the chuck up 3 points to support the bearing and put it up to the crown(takes a little practice)hint=start the drill running slow then mate it to the crown and turn slow about the same amount of turns, use the JB in the same fashion. It works and it's cheap. I've seen BRest guys do it and then shoot 0's & 1's after having done it. Gotta bad nick repeat the same procedure multiple times. Make sure to get all of the JB outta the bore before you shoot it. Hope this helps

 

[Paul Workman]

The crown:

It is extremely important that the circumference of the crown be perpendicular with the axis of the bore. As for angle of departure, beit 90 degrees or "flat" or dished (11 degree is said to be "the" angle to use), or something else - the debate has raged and continues to rage over just what is the best angle. What is not argued is the importance of the crown cut to be perpendicular to the bore.

That said, the crown tools you mentioned will allow the home smith to do a pretty decent job of re-crowning a barrel. The 90 degree cutter squares up the end of the barrel, and the 11 degree tool cuts what is one of the more popular crowns.

Although the quality from the hand crowning tools can be excellent, if one can have it done on a lathe, a truly superb job can be done for about $125. Since the 90 degree facing tool and the 11 degree crowning tools and a drill motor stud is going to set you back $150, you really might want to consider how many crowns you might be cutting - especially when considering that lapping (covered next) will probably do what you want, 95% of the time.

There are a couple lapping tools from Brownell's, but the one I have and have had great results with is the brass stud with the ball end. (The sell different sizes for different calibers. The one I have has done .17 to .243 with terrific results!)

I plug the bore with a patch to keep lapping compound from getting down inside the bore, chuck up the brass lap in my drill, dab the end of the lap in some 600 grit lapping compound (available at most any machine shop), and I place the rounded end in the bore at about a 30 degree angle. (This is important to avoid a groove from being cut into the soft brass!! I have done a dozen or so with the same brass lap, and the end of the lap has no grooves and works perfectly)

Using medium speed I rotate the angle of the hand drill in a cw circle for about 20 rotations, and then reverse to do 20 ccw rotations. I wipe off the residue from the lap, load it up again and repeat. It usually takes about 5-10 minutes for a touch-up job. If there is a nick to be polished out, it might take longer; a deep nick and recrowning is a consideration.

Then clean for inspection. Using an eye loupe I look for a nice clean bevel cut about as wide as a pencil line at the junction of the bore and the crown. If there are no scratches remaining, then it's good to go.

To date I can report nothing but good things as result of the procedure I just went thru. As a matter of routine, I use the lap to touch up the crowns of my competition and varminters after about 500 rounds. In just about ever case I can say groups were improved, but definitely not a single barrel shot worse after the process.

I've done both the procedures you're asking about. Neither is difficult and results can be very good if you take care not to get in a hurry!

Good luck!

 

[gota]

I''l agree, but after truing,cutting my angle, and cleaning again, I'll chuck up a wooden dowel about 4 inches long. turn your drill up fast, file and sand a nice radish on the dowel, add some fine lapping compound and polish gently. Rotate both ways and angle the drill about 20 degrees as you go. Gently. Maybe 1 minute is all it takes and it will be..............pretty and will remove even the smallest bur. Merry Christmas to all and shoot 'em up. gota