Please refer to each suppressor type for specific barrel length minimums, based on your desired caliber. Listed below are general calibers you may be considering.

Enigma-338 Lapua Mag
18″ or longer 300WM/338 Lapua Mag
12″ or longer 7.62×51/.308 WIN
10.3″ or longer 5.56×45/.223
8.5″ or longer 6.8 SPC
8″ or longer 7.62×39
7.5″ or longer 300 BLK

Resolute-7.62 X 8.5″
18″ or longer 300WM
12″ or longer 7.62×51/.308 WIN
10.3″ or longer 5.56×45/.223
8.5″ or longer 6.8 SPC
8″ or longer 7.62×39
7.5″ or longer 300 BLK

Shadow-7.62 X 6.5″
18″ or longer 300WM
12″ or longer 7.62×51/.308 WIN
10.3″ or longer 5.56×45/.223
8.5″ or longer 6.8 SPC
8″ or longer 7.62×39
7.5″ or longer 300 BLK

Reticent 5.56 X 8.5″
10.3″ or longer 5.56×45/.223

Sentry 5.56 X 6.5″
10.3″ or longer 5.56×45/.223