The M576 40mm Buckshot

[grog18b]

Attached are a few photos and cutaways of two styles of US 40mm buckshot rounds. I am looking for any additional information anyone might have on the loading of the casing, the M199 to be exact. The manuals relate that it is loaded with M9 propellant. I thought M9 was a "ball" type. The M576 I fired last week had remnants of a stick type propellant. The grenade was from the late 60s, so I was wondering if perhaps they changed the loadings?

Thanks all for any additional information you can provide on this interesting piece of ammunition. GROG

 

[dano1917]

Great round

Great round Grog. One recently sold on gun broker, unfortunately I was spent out at the time. Defo an impressive piece...Dano

 

[EODGUY]

Attached are photos of my XM576E1's and E2's. According to two references I have, one dated Oct 68 and the other Feb 70, both of these rounds were loaded with 1,750 mg of M2 propellant. At this point in time, every other loading in 40mm's was loaded with the M9. I don't recall of the 576 series ever loaded with M9. Not sure what you are after regarding the M199 case. XM199E1 weighs 78.5 grains and is 1.817 inches in length. It uses the Remington primer used in cal. .45 Auto cartridge cases. The cases have a groove in the base of the case, unlike most other 40mm cases. The third photo shows two unusual XM576E2 loadings. One is a solid brass dummy engraqved "CARTRIDGE 40MM MP XM576E2 FRANKFORD ARSENAL" on the side. The other is an experimental test round loaded during the development of the round. It has a clear plastic case with a rod protruding from the top center that holds the clear plastic top in place.

 

[grog18b]

Thanks much EODGUY, I'm working on a reloadable form of the 199, and was looking for the type of powder used, and weight. Any idea of the civillian equivalent of M2? Also, if anyone has an extra sampe of the inner "H" looking white piece in your 2nd photo, and the two piece top cap for that one... I am looking to replicate those. Thanks, GROG