Does Different Brass=different velocity?

[sithlord6512]

I am considering switching from WW brass to Norma brass for my .300 WSM.

I expect the Norma Brass to have less volume, and therefore lower maximum charge. However, what should I expect velocity wise - will switching to Norma Brass result in a lower, the same, or higher velocities for a given charge versus WW brass? I am assuming (and hoping) that working up to same velocity as my pet load using WW brass will help me determine the pet load (and a safe load) using Norma Brass (assuming no pressure indicators encountered are encountered in the Norma brass at this velocity).

 

[Antelope_Sniper]

Yes. Thicker brass = higher pressures.
You will need to back down and work up again. Stop when your rifle tells you.
As for which one will give you better velocity on it's most accurate load, ask your chronograph. Nodes many change more then you would expect.

 

[remingtonman_25_06]

Yes it will make a little bit of difference, this is why you need to use cases of the same manufactuer and type.

I have 4 different cases for my 243 that I weighed last night.

R-P weighed 165.0 grains
Win weighed 160.2 grains
W-W super (the good old win brass) weighed same as R-P at 165.0 grains
Win Nickel was lightest at 157.2 grains

So from this I would venture to say that if I took my R-P and WW Super it "should" produce really close to same results, depending on the thickness of the web and internal case capacity. I could fill them up and weigh them to determine this, but I was just curious to see what they all weighed on a digi scale.

I only have a few pieces (like 20 of each) of the WW Super and Win Nickel so they'll get loaded with fouler shots and whatnot.

My R-P brass is for my varmint/coyote bullets loaded with 55 or 70g NBTs
My Win brass is for my LR target 105g AMAX

 

[Guest]

You may find the Norma brass to have higher capacity than the Winchester brass. I know that to be the case with Remington versus Norma in 300Wby, where the Remington is heavier and has less capacity.