Fireforming Question?

[ScreaminEagle]

I shot my first round through the new 257 AI the other day. It was a factory Remington 257 Roberts shell. I noticed the primer is protruding a little. Probably .020"-.030". I know this can be a sign of a headspace issue, but it was done by Pac-Nor so I would assume its good to go. I have read where some say this is normal, and others say it shouldn't happen. What say you?
Steve

 

[Sas874runner]

Maybe a loose primer pocket from the factory? I have recently seen a few problems with big company factory brass and ammunition since the shortage.

 

[ScreaminEagle]

Maybe a loose primer pocket from the factory? I have recently seen a few problems with big company factory brass and ammunition since the shortage.

It was an old shell. Probably from the 80's

 

[Sas874runner]

Well it shot and blew the shoulder out like it was supposed to I assume. I would load compare it to other cases and if it measures ok then I wouldn't worry much about it

 

[ScreaminEagle]

It shot and blew the shoulder out fine. Just the primer was sticking out. I chalked it up to a low pressure load with the added chamber space.

 

[Oldtrader3]

The factory loaded (Remington) ammo, 117 grain RN, was only loaded to a little over 42, KSI (Piezo) pressure back then. I have noticed in the older Remington factory ammo that came with my Browning .257 R, also blew the primers out probably -.003/.005 and riveted a small head on the corner of them as you described. I shot all of these old shells and reloaded them to higher pressures and they behaved normally. so I kept going with loads and had no more issues.

 

[257 Ackley]

SE -
Make sure you have the bullet seated 15-25 thousandths into the lands for the fire forming. Use a 80-90% charge load for the standard .257 Roberts in your fire forming. Too many use a light load and don't jam the bullet into the lands far enough on the initial firing. You will get a nice shoulder that will work for a long time if you follow this method.

 

[ScreaminEagle]

Thanks guys!

 

[nvbroncrider]

SE -
Make sure you have the bullet seated 15-25 thousandths into the lands for the fire forming. Use a 80-90% charge load for the standard .257 Roberts in your fire forming. Too many use a light load and don't jam the bullet into the lands far enough on the initial firing. You will get a nice shoulder that will work for a long time if you follow this method.

+1

This is how I did my fireforming for my 338-06AI ran her up to 50k and a slight jam into the lands. I never had an issue. Is that built on a 700 or an old 98?

 

[ScreaminEagle]

SE -
Make sure you have the bullet seated 15-25 thousandths into the lands for the fire forming. Use a 80-90% charge load for the standard .257 Roberts in your fire forming. Too many use a light load and don't jam the bullet into the lands far enough on the initial firing. You will get a nice shoulder that will work for a long time if you follow this method.

+1

This is how I did my fireforming for my 338-06AI ran her up to 50k and a slight jam into the lands. I never had an issue. Is that built on a 700 or an old 98?

700

 

[Oldtrader3]

I have always used about 15 grains of TiteGroup in a belted case to fireform them and it has worked fine. This is with the bullet touching the lands.

 

[nvbroncrider]

SE -
Make sure you have the bullet seated 15-25 thousandths into the lands for the fire forming. Use a 80-90% charge load for the standard .257 Roberts in your fire forming. Too many use a light load and don't jam the bullet into the lands far enough on the initial firing. You will get a nice shoulder that will work for a long time if you follow this method.

+1

This is how I did my fireforming for my 338-06AI ran her up to 50k and a slight jam into the lands. I never had an issue. Is that built on a 700 or an old 98?

700

SE,

I kinda got a wild hunch. Can you post a couple pictures of the bolt face, firing pin hole and the brass. I have a similar issue with my 280AI that might help explain it. Did Pac-Nor true and fit your action?

 

[ScreaminEagle]

SE -
Make sure you have the bullet seated 15-25 thousandths into the lands for the fire forming. Use a 80-90% charge load for the standard .257 Roberts in your fire forming. Too many use a light load and don't jam the bullet into the lands far enough on the initial firing. You will get a nice shoulder that will work for a long time if you follow this method.

+1

This is how I did my fireforming for my 338-06AI ran her up to 50k and a slight jam into the lands. I never had an issue. Is that built on a 700 or an old 98?

700

SE,

I kinda got a wild hunch. Can you post a couple pictures of the bolt face, firing pin hole and the brass. I have a similar issue with my 280AI that might help explain it. Did Pac-Nor true and fit your action?

Yes they trued it up for me. I fire formed 20 pieces today, Joel's method and everything worked great. Thanks