Does the newly manufactured Winchester M193 55gr FMJ (White Box) have the primer and mouth sealed?

No.

https://www.ar15.com/forums/general/Return-of-the-M193-Clones/5-2515258/

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I looked at some the other day and the primers had the typical LC purple seals. No idea if the case necks were sealed internally, per mil spec. This was the bulk pack stuff with an LC lot number.

The 20 rd white box ammunition might be a product of Winchester's Oxford MS plant (WMA). Since the boxes are sealed and the lot number inside, no easy way to tell without opening one. The last WMA I bought was in 20 rd. boxes. There were 4-5 different headstamp and year combinations from 2017, 2018, and 2019. Some rounds were sealed, some weren't, even in the same box. This stuff was trash. I even pulled projectiles out of morbid curiosity and found a number of them lacking the internal sealant.

I'm willing to bet it's a coin toss what you get with Winchester and Winchester/LC stuff.

Thanks Molon.
I have been buying IMI for years mainly for the sealant.
Interesting to see that PPU also seals their ammo.

I inquired at a large vendor regarding the sealing on Winchester Lake City M193 FMJ rounds.
This is his answer:
"5.56 ammunition manufactured by Lake City Armory under the management of Winchester is mil-spec ammo made under US military contract and offered to the civilian market due to contract overrun. Yes, it's sealed per military specifications."

I thought he Military stopped using M193 years ago...?

Primer pocket not sealed . . .





Case-mouth not sealed . . .




Not mil-spec.

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The Winchester LC bulk pack M193 I saw a few weeks ago had the same LC 21 headstamp and had sealed primers. Clearly some is and some isn't sealed, at least around the primer.

Which means it's not mil-spec ammunition.  If a manufacturer wants to claim that its ammunition is mil-spec, it can't pic and choose when it will actually adhere to the mil-spec and when it won't.



said no mil-spec ever

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...which is why (among several reasons) I don't buy Winchester ammunition.