New brass question

[cornchuck]

I finally got some new .308 Lapua brass. Thanks to Cabela points. I have been using Rem brass. And the load I have for my .308, I'm loading 42.5grs of Varget with a CBTO of 2.227 with Sierra TMK. I have read that I should back the load down because different case thickness. How much should I back it down? Or I'm am safe with the load I already have?

Thank you
Jason

 

[scrmblr1982cj8]

I would start 2gr below and work up again. Every time I use a different manufacturer's brass for .308, I'll start the load process over. I doubt that anything dangerous would happen if you just used the 42.5g of Varget in your new Lapua brass, but why risk it?

 

[cornchuck]

scrmblr,
Thank you for your response. I was actually thinking of starting over. And that is likely what I'll do. Just wanted to get someone else's thoughts other then what I was thinking.

Jason

 

[ShootnMathews]

I finally got some new .308 Lapua brass. Thanks to Cabela points. I have been using Rem brass. And the load I have for my .308, I'm loading 42.5grs of Varget with a CBTO of 2.227 with Sierra TMK. I have read that I should back the load down because different case thickness. How much should I back it down? Or I'm am safe with the load I already have?

Thank you
Jason

Even with the heaviest tipped match king I can find in .308" you are only .5 grains over book listed minimum. So you should be fine pressure wise. If you drop 2 grains you'll be way under book minimum which can potentially bee more dangerous than being just a little on the hot side. If you get too little powder in the case and too much air space there is the potential for a detonation of the powder instead of a controlled burn. It rarely happens but it is a real risk.

My book shows 42 - 45 grains of Varget with a 175 grain jacketed bullet.

 

[scrmblr1982cj8]

SnM,

Thanks for catching that! For the life of me I thought that the starting point on Varget was 40.0, not 42.0.

 

[ShootnMathews]

SnM,

Thanks for catching that! For the life of me I thought that the starting point on Varget was 40.0, not 42.0.

No problem. gun) I use Varget in mine. So I remembered. My accuracy node is 42.5 also.

 

[brentc]

My Lapua .308 Win brass is pretty soft and stretches pockets quickly with over max loads. The best bet is to back it down.

 

[KEB0]

Why don't you fill one of your old cases and one of your new ones full of some ball powder and weigh the powder. Repeat a couple times for an average. Might be interesting.