Unfamiliar 308 headstamp

[Ike666]

I was sorting and prepping 308 brass today and came across a headstamp I have not encountered before. Can anyone ID it for me? Also, are the three, symmetrical marks around the primer stake/crimp marks for the primer?

[IllinoisCoyoteHunter]

American Tactical 7.62 Brass

Turkish stuff, kind of ironic

Yup, gotta remove those stakes/crimps

It is boxer primed, but have no experience with it.

[Mike Irwin]

It's Turkish surplus made by Makina ve Kimya Endustrisi

American Tactical was one of the importers, it was not a manufacturer.

Yes, the marks are primer stakes. Doesn't look like it was a very well done job.

[Unclenick]

I've never seen the purpose of the tiny staked crimps in HXP .30-06 brass, either. Fired primers push right out and new ones often go in unimpeded afterward. I can't imagine they actually help keep the primers in place to any significant degree; not like the more robust U.S. ammo ring crimp.

[Shootest]

American Tactical 7.62 Brass

Turkish stuff, kind of ironic

Yup, gotta remove those stakes/crimps

It is boxer primed, but have no experience with it.

^That’s right

A useful link for next time.

http://www.afte.org/ExamResources/ga...stamp-Gallery/

[Ike666]

Thanks everybody - you all satisfied my curiosity and I learned a little something. Using the info Mike provided I researched the Turkish arms company - that make an interesting array of military and civilian hardware, of which small arms ammunition is but one part.

It does seem that if you're going to set up the machinery to do a three-stake crimp it would be just as easy to use a ring crimp.

I didn't fire these rounds (my son scrounged them from the ATF range) so don't have any experience with how it performs.

[Mike Irwin]

Turkish ammo actually has a pretty good reputation.

I've fired some of the .308 out of a friend's rifle and it was accurate. He reloads the brass and likes it.

[MR-7-45]

Is it .308 Win or 7.62x51 NATO brass. Without hijacking the thread, there some differences. Don't Berdan primer brass have different flash holes?

[Ike666]

It is Boxer primed and .308 Win = 7.62 NATO; it is the chambers that are slightly different. However, most military 7.62 NATO/.308 Win have slightly smaller case capacities b/c of thicker walls.

I don't have any immediate plans to prep and load it, but I'm not going to pitch it either.

[tom234]

The only brass I've seen with that type of crimp is US made WWII 50 BMG.

[MR-7-45]

.308 and 7.62 mm brass is slightly different. I did some digging around.

7.62x51:
Parent case .300 Savage
Case type Rimless, Bottleneck
Bullet diameter 7.82 mm (0.308 in)
Neck diameter 8.58 mm (0.338 in)
Shoulder diameter 11.35 mm (0.447 in)
Base diameter 11.84 mm (0.466 in)
Rim diameter 11.94 mm (0.470 in)
Rim thickness 1.27 mm (0.050 in)
Case length 51.05 mm (2.010 in)
Overall length 69.85 mm (2.750 in)
Rifling twist 1:12"
Primer type Large Rifle
Maximum pressure 415 MPa (60,200 psi)

.308win
Parent case .300 Savage
Case type Rimless, Bottleneck
Bullet diameter 0.308 in (7.8 mm)
Neck diameter 0.343 in (8.7 mm)
Shoulder diameter 0.454 in (11.5 mm)
Base diameter 0.470 in (11.9 mm)
Rim diameter 0.473 in (12.0 mm)
Rim thickness 0.050 in (1.3 mm)
Case length 2.015 in (51.2 mm)
Overall length 2.800 in (71.1 mm)
Rifling twist 1/12
Primer type Large Rifle
Maximum pressure 62,000 psi (430 MPa)

Same? No but darn close.
Fortunately, the M1A chamber has loose tolerances and will take a .308 casing.

[Ike666]

MR-7-45, I stand corrected. Thank you for your research!

[MR-7-45]

Just do a search for .308 win vs 7.62 and you get a lot of hits. This topic has been debated for at least 10 years or more.

The short answer seems to be that if you use new .308 Win in a M1A, it will probably work. However, it isn't recommended in a military surplus 7.62. I don't think there are any M-14's sold to the public. I wonder if Springfield Armory manufactures the M1A to a higher specification than the M-14 to handle the .308. Reloading .308 Win cases that have been fired in a 7.62 can experience separation at the neck/shoulder or separate at the web.

One site http://www.cruffler.com/trivia-June01.html points out that not all NATO standard is standard. Interesting reading.

I have fired a lot of milsurp without any problems yet. I have reloaded the milsurp brass to .308 specs without any problem (yet).

[Unclenick]

MR-7-45,

A little bit of apples to oranges confusion there. The comparison is the CIP 7.62 NATO pressure spec to the SAAMI .308 pressure spec. If you look up the CIP .308 and 7.62 NATO pressure specs, they are the same 415 MPa. The reason for the small pressure difference is the CIP test barrels locate the transducer port further forward in the chamber, causing it to tend to read about 2,000 psi lower even when firing the same lot of reference loads. NATO's own spec is 380 MPa (55,000 psi) as measured still further forward at the case mouth, making it still lower than the either the SAAMI or CIP peak measurements. Bottom line, there is no real peak pressure spec difference.

As to the different dimensions of the cartridge, you've gotten some funny information there. The .308 Winchester is just a commercialization of the T65 round that later became 7.62 NATO. My first guess was the difference is that your NATO information was expressed as a number with a ±tolerance, while SAAMI and CIP give only the case maximum dimensions with a -tolerance appended. However, when I checked the numbers your NATO numbers weren't quite small enough for that to explain it. They do, however, all fall well within the -tolerances of the .308. My second guess is they are numbers someone got by measuring loaded ammunition rather than from a spec drawing.

I have a 7.62 NATO drawing in the QuickLOAD database, as well as the SAAMI and CIP drawings for .308, and they show dimensions to be identical. Here are a few sentences from a letter from Sellier & Bellot in response to an inquiry by a member at The Sniper's Hide forum asking the dimension question:

Originally Posted by Sellier & Bellot

Czech Republic is member of the … C.I.P…{and}…NATO. So we have drawings of C.I.P. of the cartridge 308 Winchester and we have also drawings NATO of the cartridge 7,62 x 51. I can you assure that the dimensions of 308 Winchester and 7,62 x 51 are the same.

The full letter is the 16th post #888086 in this thread. It also covers the pressure discrepancies. A good rework of the CIP .308 Winchester drawing is in the Wikimedia Commons here. The only difference I spot with a cursory overview is the 2.800" max C.O.L., vs. SAAMI's 2.810" max COL.

Here are your SAAMI/CIP dimensions for .308 with the minimum and maximum numbers from the tolerance added to give you ranges and a few decimal points corrected:

.308win (SAAMI)
Parent case .300 Savage
Case type Rimless, Bottleneck
Bullet diameter           0.3050 – 0.3090 in  ( 7.773 –  7.849 mm)
Neck diameter             0.3355 – 0.3435 in  ( 8.522 –  8.725 mm)
Shoulder diameter         0.4460 – 0.4540 in  (11.328 – 11.532 mm)
Base diameter             0.4623 – 0.4703 in  (11.742 – 11.964 mm)
Rim diameter              0.463  – 0.473  in  (11.76  – 12.01  mm)
Rim thickness             0.044  – 0.054  in  ( 1.12  –  1.37  mm)
Case length               1.995  – 2.015  in  (50.67  – 51.18  mm)
Overall length            2.490  – 2.810  in  (63.246 – 71.374 mm)
Rifling twist 1/12
Primer type Large Rifle
Maximum pressure         62,000 psi (427.5 MPa)

SAAMI drawings are here.

There are, indeed, chamber differences. They eliminate the overlap the SAAMI spec allows for maximum cartridge and chamber length, and widens a little to promote smoother full-auto function. There is also a longer freebore for accepting military specialty bullets with ogives further forward than commercial loads. A good set of comparisons of chamber dimensions for .308 and .308 match and 7.62 NATO is here.

NIck