Silencerco Omega

[NugginFutz]

+1

Gemtec HVT stacks up well for SBR use:

http://www.gem-tech.com/store/pc/HVT-THD-10p91.htm

Features:
Caliber: 7.62mm NATO / .308
Sound Reduction: 30 dB
Length: 8.2"
Diameter: 1.5"
Weight: 24 oz.
Material: Stainless Steel
Finish: Matte Black Cerakote with Reduced Visual-IR Signature
Mount: 5/8-24 (2A) Thread


For Barrels:
16" or longer 7.62x51/.308 WIN
10.3" or longer 5.56x45/.223
10.3" or longer 6.8 SPC
8" or longer 7.62x39
7.5" or longer 300 BLK

(Emphasis mine)