300 WSM - Brass Issues

[RDA 226sig]

In starting to work up some 300 WSM loads I used some one fired plated brass and some fresh Winchester Brass. All were sized full length and trimmed to the same length but after loading the Plated Brass would not fully chamber.

Turns out that the shoulders on the Plated Brass flared when the bullet was seated (NO CRIMP WAS APPLIED). Maybe the Plated brass is a bit more ductile or has a bit too much neck tension. Maybe I will just pull the ones in the plated cases and toss that brass....I hate though cuz it sure is pretty all loaded up...pretty useless if it won't chamber though.

 

[sourdough44]

'Once fired', you gun or another? Did you slightly(maybe more needed) bevel the mouth to accept the bullet easily? So your seating die is adjusted up enough so no 'crimp' is crumpling the case? Will the empty sized/trimmed case chamber in your gun O.K.? If the shoulders 'flared' when the bullet was seated it sounds like it was fine up to then. Of course the easy solution is to start with new brass or loads fired in your gun. It's also easier to keep a case in spec to chamber when it has not been loaded & fired at max pressures.

 

[243winxb]

has a bit too much neck tension.

Check your expanded ball diameter, should not be smaller than .306" Chamfer the case mouth more.

 

[RDA 226sig]

The case mouths were chamfered but the 180 Nosler ballistic tip should work feed with or without a chamfer.

 

[hoghunting]

Did you verify that the sized brass would chamber in your rifle?

 

[243winxb]

Turns out that the shoulders on the Plated Brass flared when the bullet was seated (NO CRIMP WAS APPLIED).

Are you sure? If using Lee dies, the seater die tapers first , then turns into a roll crimp. I would back the seating die out more and give it another try. After flrsing of course.

 

[RDA 226sig]

....well...after a bit more measuring the shoulder is within specification but the body length is not. I set the die up with the new brass and then resized all of the brass including the once fired brass at the same time. The press - an old lyman that I have had for 25+ years - has some extra flex with the once fired 300 WSM brass due to the higher forces required. Generally it isn't a problem as most of the brass is fired already and the deflection it is taken into account in my initial die adjustment.

No problem..bullets pulled and brass resized with adjusted headspace. Live and learn.