Re: Gemtech Quicksand for precision rifle?
I have one, however I don't have a precision rifle. I use mine on AR SBR's, a Handi Rifle, and a Remington Model Seven, all in 300 BLK. Averaging all my rifles together, I can say it does not open up the groups, in some cases it nicely improves groups. When using subsonic ammo, it lowers the impact point. When using supersonic ammo it raises the impact point.
I do want to mention that on my Model Seven, with the Phantom style Quickmount in place, with ammo the rifle likes, but without the suppressor mounted, the groups would rise 4" at 100 yd and would enlarge from 1 1/2" to 3"! With the Vortex Quickmount in place (no suppressor mounted), the groups would rise 2" at 100 yd, but would remain the same size. That Phantom mount was later tried on other rifles and worked fine, not causing the groups to enlarge. The Model Seven has a skinny bbl which is apparently very sensitive. I mention this because unless you intend to shoot 100% suppressed, you will also need to fire for accuracy and impact point with the Quickmount in place w/o a suppressor. I am happy with the suppressor. The rear of it comes apart so you can clean the mounting mechanism and brush out the blast chamber area.