Posted on 04/29/2017 9:01:09 AM PDT by MtnClimber
Marine Corps Systems Command is equipping Marines with the updated M2A1 .50-caliber machine gun, increasing Marines survivability and lethality on the battlefield.
The M2A1 is an upgrade to the legacy M2 machine gun currently used by Marines across the Corps. The updated M2A1 is easier and safer to use due to three major changes: a quick-change barrel, fixed headspace and timing, and a flash hider that reduces the weapons signature by 95 percent at night, according to a recent Marine Corps Systems Command press release.
M2s are the most reliable heavy machine gun, said Maj. Harry Thompson, team lead for General Purpose Weapons at MCSC. The improved M2A1 makes Marines more lethal because theyre able to get rounds down range quicker. Marines will have better mobility because of the fixed headspace and timingits much quicker to move the gun from position to position and put it back into action. Because theyre less exposed, Marines will have better survivability too.
The current M2 requires Marines to manually set headspace and timing before firing, after assembly, and after required barrel changes when the barrel becomes extremely hot from high volumes of fire. Headspace is the distance between the face of the bolt and the base of the cartridge case when it is fully seated in the chamber. Timing is the adjustment of the gun so that firing takes place when the recoiling parts are in the correct position for firing.
(Excerpt) Read more at kitup.military.com ...
Sounds like some needed improvements.
I recall that darn guage wedge we had to use on the Ma Deuce.
But as for reducing the signature?
There’s nothing on earth like a Man Deuce tossing half inch chunks of junk around.
Happiness is a Ma Deuce.
Semper Fi.
L
If it wasn't for the imagination and hard career-damaging work that Major Jim Nelson did in '93, we wouldn't have the M240 machinegun instead of that cheap M60.
It would be a good thing if the Corps started promoting officers to Generals with a technology degree instead of sticking to Physical Education Majors.
“The updated M2A1 is easier and safer to use due to three major changes: a quick-change barrel, fixed headspace and timing, and a flash hider that reduces the weapons signature by 95 percent at night, according to a recent Marine Corps Systems Command press release.”
Changes that could have been made DECADES AGO.
No doubt. No sense it taking your attention away from where it should be. I'm sure these guys can change a barrel in no time flat, but less time flat is always better.
Theres nothing on earth like a Man Deuce tossing half inch chunks of junk around”.
That’s for sure.
Headspace is the distance between the face of the bolt and the base of the cartridge case when it is fully seated in the chamber.
I’m not sure this is right. Or else I have understood it wrong over the years. I’m not a reloader.
I laughed when smartphone decided to “correct” Ma to “Man”.
That is correct. For rounds that headspace on the shoulder, the base of the cartridge may not be on the bolt face if the headspace is off. When fired, the case will stretch until the base of the cartridge hits the bolt face and the stretching could cause a case rupture.
That was the nice thing about the M-85 version of the .50 cal on the old M-60A2, it had a set head space and timing, no need for a guage or the M2 adjustments.
If the headspace is too long. If too short it won’t chamber or when fired won’t extract. Headspace is not the length from base of cartridge to bolt face. It’s from chamber to bolt face. You adjust headspace at the barrel/receiver. The bolt itself has no adjustment.
That is correct for cartridges that headspace on the shoulder of the cartridge. Some magnum cartridges have a belt in front of the rim and the round headspaces on the belt. Rimed cartridges like the 30-30 headspace on the rim.
War. War never changes...because the 1911 and Ma Deuce will always be there.
Primary headspacing is usually set as you describe - where the barrel and receiver join (at least for most 20th-century military rifles). There are oddballs, though - in tilting-bolt designs like the SKS and the FN-FAL, headspace is tweaked by adjusting the thickness of the bolt locking shoulder. The HK G3 (HK-91) and its small-bore relatives rely more on bolt-to-bolt carrier gap than headspace, due to the roller-locking design being adjustable with different diameter rollers.
Lol.
I know the photo at the article is a training facility, BUT if it were a hilltop position, it would be formidable. They could spit out some firepower!
How do they not have to time it, though? The barrel and bolt recipeocate independently. Must be some funky connection or some genius
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