First off, I'm using Winchester brass with some cheap Remington large rifle primers I found. (already have 2 duds in 15...they suck) I am using Unique under toilet paper and a case full of COW up to the neck, then plugging it with paraffin wax.

I started off at 10% of a full case load, only 3 grains. (not sure why only 30 grains Unique fit) Nothing at all happened at 3, at 4.5 I had a slight rounding of the shoulder, but the case wasn't much wider. 5 grains was about the same. I jumped up to 7 grains and it got better, looked like a Weatherby shoulder. Kept getting slightly better until 9 grains when it looked about fully formed. Going to 10 grains didn't do much more. Looks like the only way to get the final sharpening of the shoulder will be to fire with bullets.

I've tried the COW method. I used Bullseye. What I found was pretty much like you did. I can get a formed case but the shoulder was still just a touch round. What I did find was the capacity was basically the same as a fully formed case. Load and go it will have a sharp shoulder next time.

Might want to look at this and read about fireform with Unique. Myself I use Bulleye for my 6RemAI start around 12grs and work up can get about 95% of the sharp shoulders using COW and if you measure case capacity against a sharp shouldered case it's less than .3th of a gr and I haven't found that to effect anything. On forming my 280AI brass I got sharp shoulders at 16grs of bulleye. Well good luck.

I just used Unique because I also use it for my 45-70. Very versatile powder!

Tyler

As I remember, i used 17 grains of Bullseye with a 1/4 sheet of TP and nothing else. I've never seen the need for the COW. It only makes a big mess and doesn't form the case any better than TP. Even the TP isn't needed. It's only there to keep the powder in while you're driving to the range and while loading the cartridge. Red Dot works about the same as BE.

Are you POSITIVE that those misfires were the result of bad primers? If you do not have a good solid crush fit the same thing will happen.

Ray

I like to tinker and do something cheap as much as the next guy, but that sounds like too much work.

I have taken to using the cheapest bullet I can find seated out to the lands, with the minimum "book" loading of the cheapest powder I have.

It seems to get me a perfect result the first time every time without all the fuss of cream of wheat clouds, parrafin, napkins, etc.

Yes, I admit it's pretty slow, but this way I get all the barrel life possible. Also, I just open the basement door and shoot outside, no clouds of anything. BTW, wax and toilet paper will go into a 1 inch thick piece of plywood at point blank range.

quote:

Originally posted by tom holland:
Might want to look at this and read about fireform with Unique. Myself I use Bulleye for my 6RemAI start around 12grs and work up can get about 95% of the sharp shoulders using COW and if you measure case capacity against a sharp shouldered case it's less than .3th of a gr and I haven't found that to effect anything. On forming my 280AI brass I got sharp shoulders at 16grs of bulleye. Well good luck.

I forgot to post this
http://www.6mmbr.com/260AIforming.htm

I form 17 mkIV and 17 javelina by just forming and loading like normal its ben accurate enough to load this way and shoot crows with out to 300 yards. the javelina realy has to blow out the case so I notice alot more fliers with it. the way to ge is get a contender and chamber a pos barrel and fire form in it. Jeremy

RB in NM

I agree with you up to a point. That point being the number of cases you have to make. A long range Benchrest barrel in 244 Ackley is good for about 800 rounds if you're lucky. I don't want to use up 200 of those in fire-forming so I use BE and TP. Even BE & TP will use up some of the barrel, but not near as much as 200 bulleted rounds.

JMHO

Ray

Cheechako,

Given your set of conditions, anything to extend the barrel's life for your application would be worthwhile.

I've wondered in the past if anyone uses a longer than normal barrel for forming brass, or just breaking in the barrel with some bullets going down the bore, then shortens and re-reams it gains an advantage.

I have no idea if a benchrest quality barrel would shoot better or worse if this was done.