LSAT light machine gun and rifle

Lightweight Small Arms Technologies (LSAT) light machine gun (LMG) and rifle project is coming along nicely. Tony Williams, sent me photos and project’s latest news.

LSAT rifle © Tony Williams
caseless ammo (middle) © Tony Williams

The LMG now weighs 9.21 lbs in plastic-cased-telescoped (CT) and 9.9 lbs in
caseless (CL), compared with 17.5 lbs for the M249. RoF is being held down
to 600 rpm, as preferred by the military; the gun uses a “long, soft recoil”
system without a buffer, which sounds like the STK Ultimax. Modifications
have taken place to the barrel handle, bipod and buttstock to approach
military standard.

Ammunition weights now 8.3g (CT) and 6.3g (CL) compared with 12.2g for M855.
Plastic MG links weigh 0.5g instead of 2.0g for steel.

It is clear that the CL is proceeding at a much slower rate, there are still
some technical issues and the propellant is very costly. Only about 1,000
rounds have been made. The CT version is forging ahead, however. The round
is currently in its third version (“Spiral 3″) which is achieving 41% weight
and 13% volume reductions over brass-cased ammo (CL: 38% volume and 51%
weight reductions). Over 10,000 rounds have been fired of Spiral 2, without
problems, with some 400 rounds so far of Spiral 3. They are now
“productionising” the ammo; it looks as if CT will be cheaper to produce
than M855, with packing the propellant in the case being the main technical

There are currently two working LSAT MGs with a third being made; by May
2011 they plan to deliver 8 guns and 100,000 rounds for “military
assessment” (not qualification).

The LSAT rifle has just been fired for the first time. It uses a rising
chamber with an aft feed, which means that although the 42-round magazine is
ahead of the pistol grip, the barrel is actually 4 inches longer than an M4
of the same total length (24.75 inches total with buttstock folded), which
takes it half-way to a bullpup.

It is sounding like a very compelling package.

LSAT light machine gun © Tony Williams
LSAT light machine gun © Tony Williams

[ Many thanks to Tony for the photos and infomation. ]

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • sturmgewehr

    Looks interesting, am I to understand this uses a new kind of caseless round? In that case I imagine heat dissipation could (would? I imagine smarter people than I are working on this … ) be a problem. My understanding is that heat build up killed caseless ammo in the past, as a little known purpose of the brass in a conventional round is to take heat from the gun. With a full-auto machine gun, with a skinny barrel as shown in the photo, wouldn’t heat build up be even worse?

  • Zulhimi

    If the bullet propellant is the case itself in the CT version, can the bullet still fire after exposure to water? If not, then this ammunition is not useful in heavy rain, much like a musket.

  • To clarify: the belt of red ammo in the middle of the ammo picture is the caseless type, which is making only slow progress (and many believe will never overcome the technical difficulties). The belt of black ammo on the right is the current version of the plastic-cased-telescoped ammo on which LSAT is now focused, and which they say is close to being production-ready.

    Incidentally, while the development work so far has been on a 5.56mm version which matches the ballistics of the M855 simply in order to make comparisons with the M249 and its ammo, the technology is scalable so the guns and ammo can be made in any calibre. That opens the possibility of a new intermediate (6.5-7mm) round with enough performance to replace the 7.62mm as well as 5.56mm, but weighing no more than the current 5.56mm.

  • Vitor

    The semi-bullpup thing is quite fascinating. Beg for a video of this thing in action, Steve!

  • HK made G-11 work, after a lot of money. Caseless can work if you have the money to blow.

    I think Ares Defense is prototyping those rifles and LMGs.

  • kcoz

    This could very well be the next big leap foward in small arms technology that everyone is waiting for. Wonder if it will ever be made available to us civies,and what it would cost.

  • wos

    Heat is not a problem – Dynamit Nobel / HK solved this problem back then with a high temperature propellant. Water isn’t a problem either – they even threw the G11 caseless ammo out of a helicopter to test it’s ruggedness. But that stuff was expensive to manufacture and then came end of the cold war…..
    I guess (as in “I have no idea” :D) that this newer caseless ammo is even more advanced.

    I think caseless ammunition could/should solve all the problems associated with bullpups. Shoter lenght of pull for use with body armor is easy to achieve because the moving parts require a lot less space behind the magwell. There would be no problems with weakside transitions anymore – no ejection ports neccessary. What are they waiting for? Why not a bullpup? The Israelis already did a great job with the micro tavor, but caseless would be perfect for a bullpup. just my 2cents 🙂

  • William C.

    In my opinion the LSAT program provides the best chance for the US to get ammunition in a new caliber that could largely replace the 5.56mm.

  • Clodboy

    “If the bullet propellant is the case itself in the CT version, can the bullet still fire after exposure to water? If not, then this ammunition is not useful in heavy rain, much like a musket.”

    I think you mean the CL (caseless) ammo – the CT (which seems to hold the most promise) uses a plastic casing.

    I’m pretty sure the CL propellant will be somewhat waterproof, perhaps even using a combination of multiple propellant formulations, with the outside of the cartridge being the most resistant to water.

  • Lance

    It looks like a new technology which needs time to develope and I think in 10-20 years this could replace world wide cartridge ammunition. Still pronlums like extraction and moisture can still be a problem for the caseless design this has been around since the 1960s and never really took off. But give it 21st century sloutions in 10 years who knows.

  • kvalseth

    Any word on the magazine’s feed method? They were investigating weapon powered magazines earlier, but there’s nothing in that picture that suggests it’s not spring powered.

  • Maverick

    this technology was actually in Halo

  • Caseless

    HK and Dynamit Nobel had completed field testing for the caseless ammo used in the G11 rifle back in the late eighties. The cook-off issue was resolved before 1990. I assume LSAT used the plastic covering because their weapon is belt-fed.
    P.S. a quick search on the net revealed that LSAT did license the caseless ammo technology from Dynamit Nobel.

  • Jim

    Those rounds in the middle look like pieces of a Slim Jim. Have we started firing dried meat at our enemies?

  • Josh

    Hmmm. LSAT huh? Couldn’t they come up with a better acronym? Maybe – Army Combat Technologies (ACT), or Military Combat Arms Technologies (MCAT). How about General Military Arms Technologies (GMAT), or General Rifle Experimentation (GRE)?

  • Nadnerbus

    So I guess that standard 10mm exploding tip caseless aught to be ready in time for the adoption of the pulse rifle. Sweet!

  • KP

    @ Josh.

    I normally don’t post anything here, just read but.


  • Bora

    I wonder after the caseless ammo is fired, is anything extracted from the chamber? or does it ALL turn into dust? is there no ejection port? doesn’t it cause a lot of buildup?

  • Etienne

    Bora – I suspect that the chamber is cleared of debris by feeding the next round; after firing, the chamber swings from the firing position to the loading position, where a rammer loads the next cartridge. I suspect that this action would force any debris or residue out of the chamber, though I don’t know if it is designed to then allow any such detrius to fall free of the gun or if that could gum up the action (I suspect that if this occurs the designers have come up with a solution).

    I simply hope they can reduce the ‘bulkiness’ of the weapon systems, and of course that they adopt a more effective bullet to fire from these fancy cartridges and weapons.

  • Bora

    Thanks for the answer! The projectile also seems to be completely covered with propellant, seems a bit weird since there would also be propellant burning in front of the projectile, wouldn’t it?

  • Etienne

    As I understand it, the propellant isn’t homogeneous – a ‘first stage’ ignites, forcing the bullet into the barrel, followed by a ‘second stage’ (i.e. the rest of the propellant) which fires the bullet out of the weapon. Hence “Cased Telescoping” cartridges.

  • Lance

    After reading about all these why the action is suppost to operate under ideal circumstances I dont think these would be a ideal combat system yet. Untill they simplify it.

  • charles222

    Yeah, most of the stories about heat dissipation/etc with the G-11 are bunk; the cost of rehabilitating East Germany is what really killed the program.

  • mechamaster

    Caseless ammo work better in machinegun because it’s open bolt weapon. The risk of cook-off is eliminated slightly.

  • Sam Suggs

    caseless is never going to happen its to brittle and difficult to exstract a failure