Sig Sauer is diving big time into the military small arms big time in the last few years. Once mainly a pistol manufacturers with a few rifle offerings is turning into some thing like HK and FN, that supplies everything from pistols, rifles, SMGs to GPMG. Sig actually goes one step further with suppressors and optics.
The SLMAG is a multi-calibre machine gun. The calibre specific components are the barrel, breech block and the feed paws. It is sort of a response to the General Dynamics 338NM Medium Machine Gun, but it is also a direct challenge to the aging FN MAG58/C6 and the newer HK MG5. At 20lb dry with extensive aluminium construction, the SLMAG is turning FN MAG58 / C6 into an obsolete system with a lot of advanced features.
First of all, SLMAG can be fed from left or right, and it can also eject links and casings left or right. The change can be done by simply punching out a roll pin to reverse the feed paws. To reload the SLMAG, there is no need to open the feed cover to place the new link on the feed tray. The user simply pushes the link into feed tray from the side entrance, and there is a mechanism in the feed tray that will "click" the link into the feeding position. No more reaching over to place link on feed tray, fighting the link while it is sliding off.....
The early model and including this model have a Negev like arrangement, but the production model will have a side opening full length feed cover that allows full access to the breech block. SIG promises a 100% zero retention for optics mounted on the feed cover. Also like the HK MG5, the barrel can be changed without retracting the breech block to the rear, so last round off the link the barrel can be changed immediately.
Sig also indicates the feel recoil of the first round is less than 5 lb, so to ensure first round hit. So if the gun is zero-ed with a decent optic, it is capable of achieving first round hit at point target. In a way, it is an area weapon that can do the work of an "automatic rifle" if needed. Unlike the FN MAG and C6, the SLMAG also has "mlok" like slots in the underside. This allows attachment points for future development of ammo carrying system.