NATO marked brass

[sammass]

Are all manufacture's brass considered 'military' if it has the NATO mark (O around a +)? Or is there some other hierarchy to be considered. Winchester produces WCC & date marked NATO 7.62 ammo and commercial Winchester 308 Win. Federal produces both a 'FC & date' and an 'FC 308 WIN', each w/o a NATO mark. They appear to be 7.62/308. Is one military and the other commercial? Or??? Again, the brass weights differently. Seems like there are gobs of variations.

Any good rules of thumb if you are unsure of the parentage of the brass?

Thanks.

[milotrain]

NATO and commercial will be different even among the same manufacturer.

My rule of thumb is to focus on a headstamp and not bother with range brass.

[Syntax Error]

Theoretically they should be uniform, but they will have varying H2O grain capacity. To be safe you probably want to do 90% of .308 load data because of the reduced case capacity versus commercial .308 brass leads to higher internal pressures.

[bigedp51]

All Lake City and commercial contract military ammunition must meet the same U.S. milspec requirements. Meaning thickness or hardness of the cases because they will be fired out of larger diameter machine gun chambers.

"BUT" as stated above the case capacities can vary and foreign made ammo can be made to other specifications. If your going to shoot mixed brass then keep your loads on the light side for the thicker cases with less case capacity.

Or just stick with one brand of case like Lake City and sell off the rest.

Below is an example from Quickload showing the same powder charge in .223/5.56 cases with the most and the least case capacity and approximately 6,000 psi difference in chamber pressure.

[hermosabeach]

OP
For hunting and accuracy, I only use known brass.

For blasting, plinking, having fun, I will shoot a lot of random brass
Is you question more about the science behind the NATO spec brass or can you mix brass from 5 nato manufacturers and have match hand load performance?

NATO normally means crimped primers - either staked as you see from South America or a roll crimp.

Break a decapping pin when removing the primers, not seat the new primer correctly. Damn crimps

I toss the stake crimped brass. I am not sure why, but i have not reloaded the staked brass.

[J-cat]

Generally speaking, NATO marked brass has less capacity and requires a reduction in powder to stay within established pressure limits. Specifically, in the case of 308 FC, there is no difference in capacity between commercial and military cases. Winchester commercial 308 has way more capacity than WCC. 2 grains more. In the case of the 223/556, there may or may not be a difference. It depends on the brand and the year. There are 86gr cases and there are 103gr cases. Naturally, the heavy cases will have less capacity.

You can sort or not, but running one load in mixed brass may result in poor accuracy unless all the cases have similar capacities. But if you're gonna fo it, know what you have. Don't do it blindly.

[sammass]

OP Is you question more about the science behind the NATO spec brass or can you mix brass from 5 nato manufacturers and have match hand load performance?

HB... Perhaps a little of both since you asked...

I was interested in how you identify 'military' brass from different manufacturers, and, if the 'military' quality brass from say 5 NATO manufacturers was in fact, built to the same specifications. In effect, are they interchangeable? Or, are they considered 'good enough for government work' and questionable from the git go, since it is fire and forget.

Whether, if mixed, they would be match, hand load performance would be problematic, imo. However, all matched head stamps, previous fired in the match chamber, inspected, & properly prepared, I would use them for a match.

I have no idea of the original specs as far as metallurgy. Suspect that was a multi-national committee consensus. I understand that the case is built stronger to withstand the chamber variations in various weapons from various countries. The advantage I consider that the military case could be reloaded more times than commercial - thinner - brass, especially with unfired surplus ammo. Range brass pickups may only be recyclable or you might get one firing out of it as a plinker. Perhaps one is better than none. :-)

Thanks for the questions.

[baih777]

best way,
Process your brass ready to load.
Weigh cases at random and record there headstamp.
I do this for all my brass. i only load 223 and 308 for now.
you will see the differences. if I have different headstamps weighing the same, I might load 5 or 10 to see how they shoot compared to a similar weight. these are my semi auto plinking ammo. I don't mix brass for my bolt action.