Laquered and Steel Cased Ammo

[Morales]

Does anyone know why surplus ammo from the (former) Eastern bloc is laquered. I know why its generally made of steel, but I wonder why it has coatings that are often colored. I have some mil surp 7.62x39 (M43) and some 7.62x54R, and its got a paint-like coating. Doesn't this stuff melt in hot chambers of semi-autos? Can't it lead to fouling? Please enlighten me.

[Shane916]

The lacquered supposedly causes more problems in regards to jamming up the firearm. I would assume they switched to the polymer coating to attempt to avoid that problem. I've only used the newer polymer coating Wolf and it works well for the price. I don't believe they make the lacquered coated ammo anymore.

[Morales]

Interesting. But my question is why did they make laquered cased ammo to begin with?

[grammaton76]

Interesting. But my question is why did they make laquered cased ammo to begin with?

1. It helps seal out moisture when your crimping is unreliable.
2. Some folks have surmised that it delays the point where the cartridge "pops", thus allowing pressure to build up more when using a lower powder charge. This has been blamed for a number of kaboom's using Wolf ammo. In a typical cartridge, your only vector for excessive pressure is overcharging... Wolf also had to worry about over-lacquering too.

[courteousgavin]

I think Grammaton might be talking about the red laquer sealant that they put around the case neck.

But the main reason for coating the casing in laquer is to prevent the steel casing from rusting.

[grammaton76]

I think Grammaton might be talking about the red laquer sealant that they put around the case neck.

But the main reason for coating the casing in laquer is to prevent the steel casing from rusting.

Ahh, very good point - I was indeed misreading the question and interpreting it as pertaining to the neck. That's an interesting point on the casing...

[M. Sage]

I shoot a lot of lacquered 7.62x54R, and my rifle doesn't hate me. I have found some scraped-off lacquer in the chamber when I clean it sometimes, but haven't had any feed problems that I can blame on the stuff. If anything, I've had more problems with copper-washed and even brass cases.

IIRC, the lacquer is there for two reasons: to keep the cases from rusting, and to keep the cases from wearing the chamber. Same thing with copper-washed cases.

[Morales]

Thanks guys, all of you, for letting me in on that stuff. I've been stratching my head about that for months. That's the great thing about CalGuns.... tons of people can answer any question. Thanks again.

[guimus]

I run a brass chamber brush around in my Mosins after trips to the range, and that prevents any build-up of lacquer. If you leave it to build up too long, it can cause the dreaded Mosin sticky-bolt-syndrome.