(Post Ban - Available to Law Enforcement and SOT's Only)
There are some features that apparently SIG introduced on the 552 - this is the first time we have seen these:
1) There is a mechanical lockout device on the outside left side of receiver just above the fire selector, that you can rotate counterclockwise to block the fire selector from being able to select 3rd burst or full auto it can only be rotated when the receiver halves are separated at the rear end - the bottom edge of the upper keeps it from rotating - interesting part about it, when employed (i.e. rotated to locking out full auto fire), it reveals a big white dot - I suspect so range officer or team leader can confirm visually everybody is on same page.
2) they have changed the bolt handle to what I call a "Dr Seuss" style handle.
3) SIG has changed the bolt slightly - rear of bolt is drilled and added a recoil spring and kind of reverse op rod to the receiver to the rear of the bolt - first and second time I opened the receiver, as soon as I swung the upper half upward, the "op rod" launched across the room - had to do it twice before I permanently burnt into my mental circuits to open receiver slowly and catch it.
4) there is a new style flash, a three prong vortex style, actually pretty racy looking, and yes it is detachable.
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