Odd headstamps on old M193

[M90A1]

I was sorting through a can of M193 ammo that I have had for about twenty years and discovered some very odd headstamps on some of the rounds. The ones that were normal were stamped LC 89 and had the NATO cross. What I can't explain were the LC73, LC75, LC77, LC87, RA67, and TW72, none of which had the NATO cross, but did have five dots stamped around the circumference. Too, all of these rounds were packed on USGI stripper clips. Can anyone tell me what the heck I have here?

[Robb Jensen]

LC = Lake City
RA = Remington Arms
TW = Twin Cities

[m1a_scoutguy]

Here is a good link with lots of good Info !! Robb Nailed it !!!
http://cartridgecollectors.org/headstampcodes.htm

[M90A1]

LC = Lake City
RA = Remington Arms
TW = Twin Cities

Thanks Robb, but I knew that much. The main thing that struck me as odd, was the lack of the NATO cross on G.I. ammo. Got an explanation for that? Was the ammo not NATO standardized until after this stuff was made?

[Robb Jensen]

The 5.56x45mm NATO didn't become a NATO round until sometime in the 70s or 80s.
IIRC the M193 wasn't ever a NATO cartridge. The first US 5.56mm NATO cartridge was the M855 and then the M856.
The M856 needed 1x7 twist barrels to stabilize out of M249s and then they used 1x7 in the M16A2 when the USMC helped develop it.

[Cerberus]

I'm not real sure, but I don't think NATO ever standardized the M193 ball ammo, like they did the M855.

[M90A1]

The 5.56x45mm NATO didn't become a NATO round until sometime in the 70s or 80s.
IIRC the M193 wasn't ever a NATO cartridge. The first US 5.56mm NATO cartridge was the M855 and then the M856.
The M856 needed 1x7 twist barrels to stabilize out of M249s and then they used 1x7 in the M16A2 when the USMC helped develop it.

Now that I can understand. But, that then begs the question of why the LC89 M193 has the NATO cross. I think I'll just shoot it and not worry about it. Thanks for the replies.

[Robb Jensen]

Now that I can understand. But, that then begs the question of why the LC89 M193 has the NATO cross. I think I'll just shoot it and not worry about it. Thanks for the replies.

LC makes most of the 5.56mm brass used by the US Mil so they probably used brass that was really destined for M855.

I have a small amount of BH Mk262 that's in WCC brass.

[M90A1]

LC makes most of the 5.56mm brass used by the US Mil so they probably used brass that was really destined for M855.

I have a small amount of BH Mk262 that's in WCC brass.

Duh(slaps head)! Why do the simplest explanations escape me? I guess it would make sense to have one stamp rather than two. Thanks again. (slinks off to corner)

[markm]

Yep. You'll find XM193 with NATO crosses on the headstamp. It's not NATO ammo.