new 270 win brass deformed mouth question

[p5200]

I have some new unfired Winchester brand 270 win that has some pretty bad bends in the case mouths. What would be the best way to put these case mouths in round? Full length size them before priming or, prime and just let the bullet/seating die try to correct them? I could work the bad bends out by hand where I think the bullets will go ahead and seat properly without shaving the bullets any. All suggestions are sure welcomed!

 

[FLIGHT762]

If you have a neck only die use it, if you only have a F/L die, F/L size the cases.
This will uniform the case necks. It's common to have to do this with Virgin brass.

 

[judgedelta]

I usually size new rifle brass anyway. But maybe that's just me...

 

[frankenstein406]

I just take a round punch or even needle nose pliers to get them back to shape. Resize as normal after that.

 

[gamestalker]

I deal with this all the time with new brass, not unusual at all for them to get dinged up before they make it into my hands. Either run them through a neck die if you have one, or just use the FL die. I like to run new brass through a resizing die anyway, usually just a neck die, but FL is fine.

But I wouldn't recommend straightening them by hand, or by letting the bullets force them into proper shape. I can't imagine that working out to well, considering you said they are pretty bad.

GS

 

[Sunray]

Needle nose pliers will open the case mouths enough to get the expander button in. The die will do the rest. Works on brass fired out of M1 Rifles(cases regularly get whacked on the receiver on the way out) and other semis too.
All new brass requires checking the lengths, trimming, chamfering and deburring as required and FL resizing. It is not ready to go out of the factory.
Neck sizing is only for brass fired out of the same bolt action. It is not enough for new brass.

 

[p5200]

Thanks very much folks! If I remember correctly, when adjusting the f/l die the bottom of it should be touching the shell plate with the ram all the way up and, an empty case in the die also? this is on a Forster Coax press.

 

[witchhunter]

Adjust your FL die to just bump it back enough to chamber easily. The less you work your brass, the longer it will last. If you resize too much, it could cause headspace issues, making the cartridge too short for your chamber and stretch when you shoot it. When using virgin brass, you can just size it to the expander ball in the neck to round out the mouth.