PDA

View Full Version : Military vs civilian brass



slim1836
10-06-2014, 07:14 PM
Can someone educate me on the difference between military vs. civilian brass?
Specifically .308 caliber. How to tell the difference at a glance. I believe military cases are thicker walled but don't really know, and are the primer pockets "crimped" on all military brass?

Is load data different when using military brass?

If primer pockets are "crimped" does that automatically make it military? I've seen a red color around them also. I've read about various ways of taking out the "crimp" in past posts but do some of these cartridges get sold to the public or are the just military issue?

Any links would be appreciated in my quest to better understand.

Thanks in advance,

Slim

OptimusPanda
10-06-2014, 07:27 PM
The military loadings have the same external dimensions as commercial cases, although they are drawn on thicker brass. This has the effect of reducing their internal volume. A given charge would develop higher pressure in a military case as opposed to a commercial one. As for crimped primers theres plenty of commercial bass that has them crimped. I occasionally find 7.62 nato and 9mm nato brass on the range I go to and they all have the primers crimped in. They're fairly easy to spot they have the nato cross mark on them (its a cross inside a circle).

JSnover
10-06-2014, 07:44 PM
Yeah, you'll know by the head stamp first.

CastingFool
10-06-2014, 07:46 PM
It's my understanding that military brass is somewhat thicker than civilian brass, reducing the internal volume, which increases the pressure. That is why the experts tell you to reduce your loads when using military brass. It's relatively easy to identify military brass by the headstamp, which includes a year date (normally 2 digits) You should be able to see a NATO designation which is a cross inside a circle. You should see letters like LC, DEN, WCC, TW, FC, RA and others. LC stands for Lake City, DEN, Denver, WCC Western Cartridge company, TW, Twin Pines, FC is Federal, RA Remington Arms. Cases for the civilian market usually show the caliber designation, ie 308 Win, 223 Rem, 44 Mag, 9mm, while the military cases only show the year. AFAIK, all military cases except match ammo, have crimped primers. The match ammo I have seen show NM on the headstamp, for National Match. I have seen some remanufactured ammo that all cases had crimped primers, regardless whether civilian or military. After decapping, you need to remove the crimp by swaging or other methods. Some people use a sharp knife blade, but you are removing some metal, while swaging simply reshapes the metal. The red color you see is a sealer used to keep out moisture. Hope this helps.

JSnover
10-06-2014, 07:50 PM
There are a couple of tools for cutting out the crimp. It's not much more than a de-burring operation. Gets a little tedious if you have lots of brass but you only have to do it once.

Artful
10-06-2014, 08:06 PM
Actually last time I measured volume a year or two ago I found larger difference between foreign made brass (Laupa) and commercial (Remington) than Military and commercial.

slim1836
10-06-2014, 08:37 PM
All good info, thanks.
I guess I have not seen the NATO marking, however, I have seen some with the year markings. Guess I'll have to look closer.

Slim

Duckiller
10-06-2014, 09:17 PM
Various reloading manuals have military cases being thicker than commercial cases. Starting and maximum loads should be reduced 10%. Primers are crimped on military cases because they may be fired full auto and they don't want them backing out. Various ways to remove crimps. I think it is a mind numbing operation , but you only have to do it once. I have never run into commercial cases with crimps. They may exist. To determine if I had a military case with a commercial head stamp I would weigh empty cases. Get an average weight for military cases with a military head stamp. Weights on these cases may vary from year to year. Then I would weigh cases that I was sure were commercial. Sort by brand since weight will/may vary by brand. If you encounter crimped commercial cases you can compare weights to see if they may be military cases with commercial head stamp. I would doubt commercial cases are made to military stds. As I understand things, Federal is now operating Lake City Arsenal. I assume all munitions made at Lake City are for the military and Federal's civilian ammo plant don't make military ammo. I believe that I have read that there is no difference in wall thickness for military and civilian .223 ammo. Military ammo has crimped primers. Others may have different opinion/facts. What I have said is not written in stone

Silverboolit
10-07-2014, 11:32 AM
If you are reloading with cast, it doesn't make much difference on casing mfg. I have never seen much difference in performance either way.

facetious
10-11-2014, 04:51 AM
Try weighing some of them to see if thy are heavier.

dragon813gt
10-11-2014, 06:51 AM
As a rule you should determine the internal case volume of any military brass before loading w/ it. It's a straight forward process. And you will find out that sometimes there is no difference. And a lot of the time it's marginal.

Eutectic
10-11-2014, 09:59 AM
TW, Twin Pines,

Casting,

I believe TW is Twin Cities Ordinance in Minneapolis, MN.

Eutectic

rondog
10-11-2014, 10:39 AM
Can't recall ever seeing any .30 carbine brass with crimped primers.....or .45acp. But everything else, yes. I usually use cutters, but may have to look into a swager.

USSR
10-15-2014, 08:41 PM
A couple of statements above need to be corrected. First, not all military cartridges use thicker brass and have less internal case capacity. While it is true in regards to the 7.62x51 and .308, it is certainly not true with military and commercial .30-06 cases. There are several commercial .30-06 cases that are heavier and have less case capacity than most military .30-06 cases. Second, not all military brass has the Nato symbol on it. The 7.62x51 cartridge is produced by several countries that use it and are not Nato members. Third, as previously stated, match 7.62x51 ammo does not have crimped primers. This brass is identified by a headstamp containing: Match, NM, or LR. Lastly, regarding military .30 Carbine ammo, the only ammo I have seen with crimped primers are those produced by Winchester with headstamps of WRA or WCC. Hope that helps.

Don

M-Tecs
10-15-2014, 09:20 PM
Some data here

http://castboolits.gunloads.com/showthread.php?84074-308-Winchester-vs-7-62-Nato

Garyshome
10-15-2014, 09:38 PM
If it's crimped I call it military, but that wouldn't be the first thing I was ever wrong about.

Le Loup Solitaire
10-16-2014, 10:25 PM
38 special cases used for loadings by the military were definitely thicker. I had to size bullets .001 less to avoid wrinkling/squeezes with wadcutters. I did it and still got good groups...as good as commercial brass with bullets sized .001 more. A lot of the military brass was stamped WRA or RA and it is lasting forever. LLS

Bill*B
10-23-2014, 08:35 PM
Specific to the .308/7.62 NATO, some military cases are closer in internal capacity to the .300 Savage than to commercial .308 Winchester brass. If you are loading "hot" its worth the trouble to put them on a scale and see how much water they hold.

fastfire
10-23-2014, 10:09 PM
There are a couple of tools for cutting out the crimp. It's not much more than a de-burring operation. Gets a little tedious if you have lots of brass but you only have to do it once.

I use a deburring tool set-up in a cordless drill, make quick work of it.
With a little practice you can remove just enough to prime without issues. fwiw