SIG 556xi and 516

[gtmtnbiker98]

Any experiences out there?

[Suvorov]

I have been shooting a 516 Patrol Gen 1 primarily for the past year and a half. In a nut shell my experience with the rifle has been very positive.

I never really bought into the piston gun for my needs and so never really considered getting one. In the months that followed Sandy Hook I set about to get another M14 or AR pattern rifle as the situation in Kalifornia looked grim. I had little money so I offered to trade a USP Tactical for a rifle and someone offered me a brand new (well he said it was anyway) 516 with EoTech in trade so I took it.

The rifle has proven to be the most accurate of my non-match grade ARs shooting an average 1.4 MOA 5-round groups at 100 yards with BH 68gr Match OTM and me behind the trigger. By comparison my BCM 18 inch SPR with the same scope will group and average 1.1 MOA with me behind the trigger. YMMV.

The rifle is well built. Castle nut staked well and fit and finish are as nice as any Colt, DD, S&W, or BCM rifle I have seen. Trigger is as nice for a standard AR trigger with no grit and very little creep. The BCG is nitron finished and utilizes a standard AR bolt. Newer Gen 2 rifles have a revised BCG (LWRC sued Sig for supposedly copying their BCG) that looks to be a little bit lighter. Barrel extension and upper receiver have M4 feed ramps.

I have experienced no stoppages or malfunctions in just over 1100 rounds of shooting. There has been no evidence of carrier tilt in the receiver extension and the BCG design is supposed to deal with that. I don't get to the range nearly as much as I would like nor have I been able to shoot any classes or serious matches with it so the round count is lower than what many would shoot in a year and a half time. My rifle training "regime" is based on the CSAT standards which includes close in multiple shot strings as well as medium range (50-100 yard) slow fire and rapid fire groups. It isn't a Costa course by any stretch but it is more than simply shooting dirt clods. Magazines used have been primarily 20 and 30 round PMags converted to 10 rounds. I have not cleaned the rifle since its initial cleaning and range visit and don't intend to for another 1000 rounds or so. Sig has made a big deal about its reliability so I kind of want to see just far I can take it.

In my experience with the rifle I have noted the following issues
- The rifle is heavier than a standard DI gun. Sig lists it at 7.4 lbs empty which is just about a pound more than a stock DI M4.
- The rifle uses a proprietary gas system and as such I am dependent on Sig for many spare parts with respect to barrel, gas system, and carrier group. Maybe not the best idea if you are looking for a doomsday prepper type rifle. Then again, with the exception of the gas system and BCG, the gun is a standard AR and thus could be converted to DI with little issue.
- The quad rail is carbine length and the proprietary gas system prevents installation of standard AR rail systems. As well the gas block is not shrouded by the rail system which leaves it exposed. This has been my biggest complaint about the rifle. I'm not a real aggressive "c-clamp" type shooter but I do like to get my hand out to the front of a carbine length rail. On a standard M4 it really isn't a problem as the gas block does not get as hot as the block on the 516 can. Also rail sections can be mounted to the front sight post on the M4 while this is not possible with the 516. As a result, I recently purchased a 11 inch carbon fiber rail from Lancer Systems. This rail system is also available from the factory on the "Carbon" series of 516s. This new rail has remedied all my issues with the rail system and the lighter material gives me a lot more handguard real estate for the same amount of weight. The only real issue I have with the Lancer rail is that the rail has to be removed (it is held in place with 4 screws) in order to completely remove the gas piston. Sig is now showing a newer handguard design on their webpage that looks to shroud the gas block but have have yet to see one in the stores with this new handguard.

All in all I'm happy with the rifle. It kind of "followed me home" so to speak and has proven to meet my needs quite well. Based on my sample of one, I would recommend it to someone looking for a piston gun. That said, I really don't think it offers anything over a quality DI gun for my or most peoples needs and has some limitations (as noted) that may be real issues for some people.