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· Forum Vassal
710 Posts
Discussion Starter · #1 ·
As far as I am concerned, SIG USA is a company that just doesn't get it. Since they don't get it now, they probably never will.

However, this is something of a step in the right direction, but we still have the garbage pot metal sights that are the wrong height for the SIG 55x platform, the flash hider is balls, the rail is the same crap as the 556, and the hand guard is all wrong.

I don't especially have a problem with the aluminum lower...for now, but the magazine paddle doesn't look as easy to access as the Swiss model




- Two-position adjustable gas valve
Gas piston, rotating bolt

- Military grade barrel ensures accuracy and durability

- M1913 Picatinny rail for mounting optics
Ambi safety selector

- 7075-T6 aluminum Hard coat anodize lower receiver

SIG551-A1 Specifications

Caliber 5.56X45mm NATO
Overall Length 36.1”
Length with Stock Collapsed 34.6”
Length with Stock Folded 26.0”
Barrel Length Without Flash Suppressor 16”
Operating System Gas piston, rotating bolt
Rifling Lead 1 in 7”
Number of Grooves 4
Muzzle Break Fluted
Sight Radius 18.0”
Weight without Magazine 7.0 lbs
Magazine Type Swiss Polymer
Magazine Capacity 20/30
Trigger 2-Stage
Trigger Pull 7.5 lbs

TACTICAL PRECISION, For 2011, SIG SAUER® is offering several variants to its tactical platforms. NEW to this lineup is our new SIG551-A1, chambered for the widely used 5.56 x 45mm NATO caliber using Swiss Polymer magazines. The SIG551-A1 features a distinctive swiss folding stock, and an M1913 rail for accessory attachment. The 16” barrel features four-groove rifling and a twist rate of 1:7”. The SIG551-A1 measures 36.1” but can fold to 26”, making it ideal for situations where maximum maneuverability is required. For Special Forces requiring an accurate, more potent rifle, chambered in 5.56 x 45mm NATO, the SIG551-A1 sets a new standard for dependable operation and function.

An ISO 9001: 2000 Certified Company, Manufacturing in Exeter, New Hampshire
SIG SAUER, Inc. reserves the right to correct any errors or inaccuracies contained herein, and to revoke stated offers at any time without notice.
Prices, availability, specifications, and promotional offers are subject to change or cancellation at any time without notice.
I've got time. I'll continue to wait for something built closer to the true Swiss TDP


· Premium Member
4,922 Posts
i wonder if you could use the sig 55x (not 556) parts on it, i'd be in for a 552

· Forum Vassal
710 Posts
Discussion Starter · #4 ·
A few of these have popped up on gunbroker.

It still looks like SIG USA doing SIG USA nonsense.

Is it really that hard to add sights actually made for the gun, and a proper Swiss spec handguard?

If nothing else, for your DIY project lovers, this gets you a few steps closer in your efforts


· Registered
44 Posts
Id only need a few minutes with the girl and she would be prancin around with my acr.......and that smile....but with a slight limp :)

· Registered
1,289 Posts
Yeah, I purchased a SIG556 Classic last year. It was not money well spent. The SIG556-A1 is just more of the same cost cutting/bean counter/make as much as we can until they wise up, crap! SIG USA got this rifle all wrong too. After looking into swapping out the aluminum lower for an imported Swiss steel lower, I decided it simply wasn't worth the time and money. The original SIG 550 series rifles are selling for about 4K. I sold my 556 and my matching 522 training rifle and bought the ACR. The modular feature of the ACR sold me. Once the aftermarket and Bushmaster or Remington catches up, it will be a great platform. Hopefully this works out and I don't lose my butt like I did on the 556 and 522. Live and learn!

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