Re-sizing Brass for a WSM AR

[Earnhardt]

My problem here...

I'm using 2 different brands of brass (for comparison) in my WSM AR, Nosler and ADG ~.550" before firing at the base of the brass above the rim...after firing, the base of the brass is .555" to .560" (above the rim)

After firing the round, whether with the gas on...or completely turned off, the base of the brass will not resize to less than .555' or so, at the .200 line... with a Standard Redding re-sizing die

and I am having a hard time getting newly sized and reloaded rounds to operate properly or even cahmber without jamming the charging handle and BCG forward...

I have small base dies for other AR's I have, but not for this 358 WSM- AR

Is a custom small base re-sizing die the only hope in resizing the brass down to .550"..or is there something else I can do?

This is cross posted on Sniper's Hide

Thanks

 

[Earnhardt]

From left to right...this is the ADG brass
1) Brand New unfired
2) 9 oz buffer
3) 12 oz buffer (this brass is resized)
4) 15 oz buffer
5) Gas turned completely off

I know it's hard to see, but if you look close you can see the brass expansion at the .200 line (it expands upwards of .010", and I can only size it down .005 or so...

 

[46and2]

My range officer gave me some once fired brass, some had problems chambering in my barrel after sizing at the .2 line.
I used a 28 Nosler die to carefully size that area. Worked really well.

A 26, 27, 28, or 30 Nosler die should be able to work.

I have an extra one on hand if you need to borrow it.

 

[Earnhardt]

That is a great idea!
How about a RUM die?
They are the same brass family as the Noslers, correct?
I have a bunch of RUM dies.
Thank you!

 

[46and2]

That is a great idea!
How about a RUM die?
They are the same brass family as the Noslers, correct?
I have a bunch of RUM dies.
Thank you!

Yes sir.
I just checked my cases.
My 300rum is exactly where my 30 nosler measurement is!!

Go for it.

 

[Earnhardt]

 

[Earnhardt]

That was a great idea man!

This is the smallest sized brass so far...the others are in the .553" range

Thanks again!

 

[Earnhardt]

What sequence are you using in sizing the brass when you do this? Do you use the Nosler die first? And then the WSM sizing day after that, to bump the shoulder if needed?
Thanks

 

[46and2]

Yes,
Size base in 28nosler die
Resize in wsm die
Trim if needed