Variations in Brass

[concretus]

Hello,
I have been working up load for my 1898 Krag cut down rifle and while producing test loads noticed quite a difference in weight of R-P brass Graf brass. the Graf brass is about 20 grains heavier than the R-P...If you look at them the rim configuration is different. The R-P brass has a slight bevel from the bottom up and the Graf is squared like the 303 Brit. Would this difference in weight be similar to .308 commercial and 7.62 NATO military brass in that there would be a difference in case capacity? BTW 43.5 - 44.0 grains of H4350 in Graf brass seems to be the "sweet spot" with Sierra 175gr MK for this rifle w/ 1.5 moa. If the same charge was applied to the R-P brass, there is a possibility for different results due to a difference in case capacity and pressures, correct? What kind of accuracy can you get out of these rifles? Thanks for looking.

[madsenshooter]

I have some old REM-UMC 30USA brass that varies by as much as 30gr. I bought it once fired. Some of the heavier brass had obviously been loaded to higher pressure. Could be someone loaded the heavier brass with the same load that that they were using in the lighter brass and got the higher pressure. So, yes, those weight differences can cause a difference in pressure, velocity and results. One could work up a near max load in the light brass, put that same load in the heavier brass and experience sticky extraction or observe other pressure signs. It became apparent there were two lots in the 200 cases I'd bought and the weight variation wasn't so big once sorted into lots by weight.

[Rapidrob]

I just went through this this past month. The Remington brass is very poor and very thin in front of the web. So much so that once fire-formed the brass split at the web on the 2ND loading!. My rifles chamber is tight.
All other brass on hand has never done this. Winchester brass is rolling along after five 220 grain bullet loads and shows no signs of stretching.