New to fireforming; some questions

[Deleted old_dood]

No, I checked head space before I fireformed. I used the proper gauges. About 10 cases out of 100 gave me hard bolt lift. When I re chambered those empty cases they gave tight bolt close.

 

[LHSmith]

^^^^^ Rule of thumb: Hard to close bolt = insufficient shoulder bump/ Hard to open bolt = case web area not sized enough.

 

[MrMajestic]

Yes, I was referring to headspace in regards with case sizing not setting the barrel. You answered my question though and like Smitty said it sounds like some are long. Use your chamber to determine how much bump. Sounds like all is well, how did it shoot during breakin?

 

[Tommie]

When you headspaced the barrel did you set it so the bolt will close tightly on the 223 GO gauge? If the standard 223 GO gauge will not chamber (again, snugly) then you may be below minimum headspace. Closing the bolt on standard 223 loaded rounds shouldn't require excessive effort.

Regarding the shortened AI brass length, it's completely normal. Brass for the cool new shoulder has to come from somewhere and usually it gets "stolen" from the neck.

 

[Deleted old_dood]

When you headspaced the barrel did you set it so the bolt will close tightly on the 223 GO gauge? If the standard 223 GO gauge will not chamber (again, snugly) then you may be below minimum headspace. Closing the bolt on standard 223 loaded rounds shouldn't require excessive effort.

Regarding the shortened AI brass length, it's completely normal. Brass for the cool new shoulder has to come from somewhere and usually it gets "stolen" from the neck.

I set the barrel to just close on a Manson 223AI go gauge (no resistance with internals removed). Like several forum members mentioned, use the standard 223 GO as the NOGO. It wouldn't close at all on the standard GO gauge. As others have said, setting the barrel that way should result in a slight crush fit on standard 223 rounds. Again, with internals removed, they did. During fireforming 100 cases I had about 10 that exhibited harder bolt lift than usual. When I put those empty cases back it I had stiff bolt closure. I tried bumping the shoulder back on one of those cases with a Redding body die (Coax press). I set the height of the die to give much more cam-over than I've ever used before and there was no change to my measurement using the Hornady headspace guage/comparator tool. That FL sized case still exhibited harder than normal bolt closure when put back in the rifle.

I'll be loading all cases again and shooting them this weekend. Maybe they just need another go-round?

 

[Tommie]

The gun's headspace is short. Period.

Do as wish. I'm checking out of this discussion thread.

 

[Deleted old_dood]

figured out my problem of not being able to bump the shoulders on cases that chambered hard, apparently it's the distance from the bottom of the case to the top of the shell holder (Redding die, RCBS shell holder). I stuck a piece of card stock under the case while inside the case holder and then was able to bump the shoulder with a normal amount of press cam over. I then took my shell holder and rubbed the top on a diamond stone to take about .005" off the top. All good now.

 

[MrMajestic]

Great, you could have taken off the bottom of the die also.

 

[Deleted old_dood]

Great, you could have taken off the bottom of the die also.

don't think that would have worked. that would require that the die be lowered which wasn't working. reducing the height of the shell holder on the surface that the die comes in contact with allows the die to come down farther on the case.

 

[boltfluter]

Old dood,

With respect, you accomplish the same thing either way.

Regards, Paul

www.boltfluting.com