03 August 2005, 15:40
SanmanFireforming for Ackley Improved cases?
My shooting partner has just bought himself a Savage rifle in 223AI. It's using the factory barrel which was rechambered.
Question, He called me and asked how to fireform the cases. All I know is that he should use a light charge of a fast pistol powder to do the work. Can someone give me more of a detailed rundown as to how he should go about doing this? Thanks to all for your replies.
Rick
03 August 2005, 16:23
TailgunnerIf it was done right (the barrel gets set back and the standard GO gauge becomes the NO-GO for the ackley chamber), the bolt will be a little stiff to close on a factory round (crush fit). At that point simply fire factory ammo in the ackley chamber, no special forming needed.
03 August 2005, 17:11
tiggertateDitto Tailgunner or, if he has a bunch of new or once-fired brass he can use any max load in the books. Don't bother with many-times fired brass unless it is annealed before using it. Too brittle and you'll get a lot of shoulder or neck splits.
Don't use less than max loads, either. Often too low pressure will cause shoulder splits, even in brand new cases. Been there done that too.
Pistol powder works fine but you waste a lot of components when you could be shooting for real.
Unless he absolutely knows that the brass is a crush fit I would also recommend seating bullets to engage the rifling to locate and hold the round against the bolt face against the impact of the firing pin. The expansion of the brass will create enough buffer to keep the pressures acceptable. Lots less work than putting a false shoulder at the base of the neck with an oversize expander.
03 August 2005, 18:03
Hot CoreHey Sanman, Two excellent posts to your question.
03 August 2005, 23:20
JustCprovided the chamber is cut correctly, I jam the bullets in the lands by .010", and use a medium load of the fastest powder listed for the parent cartridge. I get perfect sharp shoulders every time.
04 August 2005, 04:20
SanmanThanks guys, I'll pass along all this information to him. He's wanting to form once fired brass for the AI.
Rick
04 August 2005, 04:31
tnekkccIf the chamber was cut long, and it sounds like it is, the way to form Ackley improved brass is with the two step process:
1) Lube the cases
2) Put some pistol powder in 3 gr or 6 gr of Unique will behave much the same.
3) Cover the powder with Creame of wheat.
4) If these can be fired straight up, fine, otherwise cover the creame of wheat with a plug from a bar of Ivory soap.
5) The brass will now have 50% of the Ackley shoulder [75% with 6 gr powder], partial neck resize and load the next round with Ackley load data and expect full accuracy.
6) Now the shoulder is 100% formed.
04 August 2005, 06:43
Collinsquote:
Originally posted by tiggertate:
Ditto Tailgunner or, if he has a bunch of new or once-fired brass he can use any max load in the books. Don't bother with many-times fired brass unless it is annealed before using it. Too brittle and you'll get a lot of shoulder or neck splits.
Don't use less than max loads, either. Often too low pressure will cause shoulder splits, even in brand new cases. Been there done that too.
Pistol powder works fine but you waste a lot of components when you could be shooting for real.
Unless he absolutely knows that the brass is a crush fit I would also recommend seating bullets to engage the rifling to locate and hold the round against the bolt face against the impact of the firing pin. The expansion of the brass will create enough buffer to keep the pressures acceptable. Lots less work than putting a false shoulder at the base of the neck with an oversize expander.
This post is a keeper! I guess you're not as blonde as your avatar
