I'm pretty sure it would not work well, due to the AI's 40* shoulder. From what I've heard/read, when the bolt carrier strips the next round out of the magazine, the sharp shoulder angle causes the round to hang up on the feed ramp and not chamber.
whacking out almost 3600fps with a 55gr sierra blitzking. http://www.insightshootingsystemsinc.com/ built it with a 24" barrel. The only trouble I have had with it is trying to shoot 223AI from my bolt gun made with another reamer. They are pricey, but so is any other custom high quality gun, he also does 20 tactical, they are shooting machines.
To look at two fireformed cases it is really hard to tell. However the reamer I started with has a very sharp break to the neck, while the ones for the AR are more of a radius on the shoulder, I talked with Lee Mosher the maker of the AR while I was trying to figure this out. He wanted me to send the upper back so he could diagnose the problem I was having feeding.
I was trying to use previously fireformed cases from my boltgun in the AR. The cases were not fully chambering. I started over with fresh fireforming and then reloaded cases fired out of the AR and voilla, problem fixed. The 3550 I posted was fireforming straight 223 cases. I use 2520 AA powder are recommended by Lee Mosher and I would tell you straight up that is not a powder I would of tried to start with, but it works really good in the AR. However lots of difference from lot to lot in AA powder. I used to be made in Communist block country but now is made in China or Israel, I think. I would have to look at a jug to see.
Lee really likes to use 26" barrels for max velocity, but I prefer shorter barrels, I can stand 100-150 less fps for ease of handling. Who can tell much difference when you get above 3500 until you get to 4000 fps.
Lee does considerable test firing before each upper leaves his hands and he knows they will shoot very tight groups. Quality, Quality, Quality.......I would like to try the tac 20 he builds but can't see how I can improve much over what I have right now.
another GGVG guy (Jim in Idaho) sent me some info about making the .223 AI feed better in a bolt gun.Your description of the 2 different reamers reminded me of his solution.......
Thanks for the info Joe....
Only thing is you have to keep the bolt with the rifle.It was an old 1-12 twist that was shot out set it back.(more work than it was worth) We found it worked good but was a pain to find the brass. Gave up on the idea after we found N-133. It was close enought for our needs.
I have two bolt rifles one I did and one by a gunsmith(different reamers). The ammo will not interchange.
If you are indeed pushing 55 gr. bullets at 3,600 fps. your are running some very high presures. You are talking .22-250 velosities from a case which has about 3/4 of the volume of the .22-250 case. I do this with my .411 hawk, I can push a 300 gr. bullet to the velosity of the .375 H&H mag. with abt. 3/4 of the case volume because the .375 is an old round and has a relitize low working presure and I`m loading to 60,000 psi. The case volume of the .223 AI. is about the same as the .222 Rem. mag. and working at the same presure levels that is about the velosity you should get. My guess is that your working presure is well over 60,000 psi. and definately in the red zone.
I booboo ed with info, actual chrono' velocity ave 3450 fps at 10 ft. Yes, I know it was a hot load. I wish I had a chrono with the pressure strain gauges. I would say these might not be summer time loads.
I changed lots of powder, anyone that uses AA powder has found huge differences between lots of recent manufactured powder. This was 2520 powder by the way. Non moly 55gr Sierra blitzking bullets.
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