• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Fire Forming Improved Rifle Cases Without a Bullet

I have done this with three sets of brass now and this last time I tracked things more carefully. The old rule of thumb is to fill the case 2/3 full of pistol powder then use Cream of Wheat, oatmeal, wax, soap, etc. to keep the powder in place. Here is how I did it this last time. Use this method at your own risk, I assume no liability whatsoever.

I fire formed about 200 Lapua 6BR cases into 6 BR Ackley. This process moves the shoulder forward a little and changes the shoulder angle from 30 degrees to 40 degrees.

I used Fed 205 primers, 20 grains of Bullseye, and 1/8 piece of toilet paper. I neck-turned these cases and cut a little into the shoulder. When I chambered the barrel I made sure that the bolt would just close on a 6 BRA go gauge.

After firing with the Bullseye and TP, the shoulders measured 1.148"-1.150" on my Mitutoyo calipers with a Whidden insert. Most were 1.1495", if I can reliably measure to .0005" with that setup (questionable). The shoulder diameter measured .463 and the base diameter measured .4685. After subsequently shooting those fire formed cases with a bullet during load development, the shoulder length was 1.149, shoulder diameter .463 and base diameter .470. I consider that close enough to begin load development. My die sizes the base back to .4685 and the shoulder is wherever I want it.

While I did not have to shoot any bullets through the bore during fire forming I knew there would still be carbon to clean out. I thought there would be a lot but when I looked with the Hawkeye borescope all I saw was a very light gray coating that cleaned up fairly easily. There was no throat erosion or fire cracking.

So far load development with this barrel is going okay, about like when I fire form with bullets.

A couple of notes.

You must use a softer primer for best results. From previous experience I know that a CCI BR4 will not reliably fire with a case neck-turned into the shoulder. The Fed 205s worked great.

The barrel gets very hot if you crank through 200 all at once. I put wet rags the length of the barrel and would shoot 50 in a row, then re-wet the rags. That was on a 40 degree day. In the heat of the summer you would have to go slower.

20 grains of Bullseye very noticeably shoots flame out of a 29.5" barrel. I don't know if I would want to try this with my 300 Ackley with 50 grains of Bullseye, but in theory it would work. Then again, with a hunting rifle I wouldn't need 200 cases--50 would be enough so I'd probably just use bullets.

If you think you need 200 rounds down your barrel before it's even worth trying to tune a load, then this method is of no value--you might as well fire form with bullets. If you think the barrel shoots it's best when its at its freshest and don't have a fire forming barrel, this method works well.

It's not any faster to stuff the toilet paper into the neck than it is to load a bullet, and you might want to wait until the toilet paper supply chain catches back up before using this method...........

Use this method at your own risk, I assume no liability whatsoever.
 
Since the COW method is currently being discussed I thought I should bump this thread up for those who may be interested.
 
Since the COW method is currently being discussed I thought I should bump this thread up for those who may be interested.

INTJ,
I read this post the other day and was going to post but saw no reason to. But been following the other one you mentioned. I have used every method I know of out there to ff various 6br improved cases. The best method for me was a false shoulder heavy flat base bullets and shoot rockchucks and whatever while ff my brass but there are times that isn’t convenient or several hundred pieces needed then I use a method very similar to yours . I did not like the mess of cow however it worked ok I ended up with I think I’m not sure but think 12 gr of unique and I think .22 cotton patch but at any rate a patch not toilet paper. I have used toilet paper just liked the patch better. I also turn my necks and false shoulder , I do 25 or so at a whack I feel that I get 95-98% finished case dimensions. In a couple hours I can do several hundred pieces. I have a dedicated rifle for this that was cut with my ream and I have ff hundreds of 6brx brass with it and lots of ground hogs!
Wayne
 
Oh to have a picture me fire forming 375 H&H to 375weatherby use TP and COW it blowing out the muzzle to the Liberal media and only say that you were using TP to Fire form loads!! RW
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
164,941
Messages
2,187,157
Members
78,614
Latest member
dlljr416
Back
Top