Fireforming Cases
- Thread starter Mike K.
- Start date
If you don't want to use a bullet, use cream of wheat and plugged with handsoap, the bar kind. A little google time and you will see what I mean. Powder behind just tissue paper does not create enough pressure to form the case.
back40sniper
CGN Regular
- Location
- South east Sask.
Best thing about using a bullet is you seat it long enough so case is held against bolt, perfectly formed case every time.
I have 3 Wildcats that require fire-forming if I have new cases [parent cases]
I put 10-15 grains of bullseye in the primed case, and fill with cream of wheat.
A little wad of TP in the neck to hold it all in place.
When I fire the case, it comes out perfect.....no barrel/throat wear either.
Regards, Eagleye.
I put 10-15 grains of bullseye in the primed case, and fill with cream of wheat.
A little wad of TP in the neck to hold it all in place.
When I fire the case, it comes out perfect.....no barrel/throat wear either.
Regards, Eagleye.
I understand the way Eagleye does it, but to just use a max listed charge, with a normal bullet just doesn't sound safe to me. Whatever happened to working up a load from 10% under to a safe pressure in your rifle. Since when is it recommended to start at max load?
No offence meant, I am missing something in the way KDX explained...
No offence meant, I am missing something in the way KDX explained...
So, if I want to fireform say 30-06 to 30-06 AI, I just find a max load for say 180 grain bullet with ###XX powder in 30-06 AI, load it up and bam, fire formed? Or did he mean a max load for 30-06 not AI, that's what I missed I guess.
One friend with a 30-06 AI simply fires store bought factory ammo to form his brass, works for him..
Yup. If you are uncomfortable with a book max, use a good standard load. And actually use the rounds, don't just bang them off to form brass and wear the barrel. They will shoot fine. It takes good pressure to fireform a case; light loads might not do it.
For fireforming .348 cases to 11mm Murata, I make blanks, with fast burning smokeless - 12 - 14gr of 700X, filler, and a cap of white glue to hold them together in transport.
Jamming a bullet into the leade in order to hold the casehead against the boltface usually works, although if the firing pin drives the case foreward, there can be less than tight headspace control. I have even loaded 160GR SP 6.5 bullets backwards in 6.5MS cases to hold the case back. Rifle had bad excess headspace, and 6.5 MS brass is too scarce to lose on the firest shot. Used starting level loads to do this.
For fireforming .348 cases to 11mm Murata, I make blanks, with fast burning smokeless - 12 - 14gr of 700X, filler, and a cap of white glue to hold them together in transport.
Jamming a bullet into the leade in order to hold the casehead against the boltface usually works, although if the firing pin drives the case foreward, there can be less than tight headspace control. I have even loaded 160GR SP 6.5 bullets backwards in 6.5MS cases to hold the case back. Rifle had bad excess headspace, and 6.5 MS brass is too scarce to lose on the firest shot. Used starting level loads to do this.
paperslayer
Regular
- Location
- Chilliwack
done it both ways. Depends on the case. Some wildcats like my 22 middlestead had such lousy barrel life, I'd wear it out fireforming with bullets. I use a bit of wax rather than toilet paper.
If the chamber is correctly set up the go gauge (minimum chamber length) of the parent cartridge is the AI no go gauge. Ackley designed the chamber so that the parent cartridge will automatically head space on the shoulder so seating the bullet into the lands is not required.
Firing a full patch (max) parent cartridge is advised to ensure the shoulder forms correctly especially with the 40 degree shoulder versions. As previously mentioned chamber pressures will be lower due to the increased case volume. I have found the accuracy with the case forming loads to be as good as the AI loads on my 6mm and .22-250 improved.
On a rechamber to AI if the barrel was not set back the chamber likely has excess headspace, you can still form the brass to match by seating the bullet into the lands , but it is not a the true AI chamber as designed by Ackley.
Dan
Firing a full patch (max) parent cartridge is advised to ensure the shoulder forms correctly especially with the 40 degree shoulder versions. As previously mentioned chamber pressures will be lower due to the increased case volume. I have found the accuracy with the case forming loads to be as good as the AI loads on my 6mm and .22-250 improved.
On a rechamber to AI if the barrel was not set back the chamber likely has excess headspace, you can still form the brass to match by seating the bullet into the lands , but it is not a the true AI chamber as designed by Ackley.
Dan
