Pappabears 12.5 BCM barrel with and without M4-2000 mounted… shooting VMAX.
Which groups were without the suppressor?
The bottom groups for both of us. Not bad. And not having a windage shift is good.
Never mind, I get it now. I didn’t see the circles you drew around the groups at first. Only a few inches in elevation change.
Yeah… unique to that barrel for sure.
Yea, the m4-2000 dropped the POI an inch or two. Not bad. Also, pretty good groups for a 12.5 CL standard (not CFH) BCM barrel.
It reinforces what has been said many times, SBR’s with decent ammo can produce some nice groups.
I did this with my DD pencil barrel (16 inches) and it was about 6 inches. There was no windage drift and it was repeatable.
distance?
100 yards, it was repeatable. POI shift was 1.5 to 2 inches. On one of my guns I feel (the can) it tightens my groups but not on this one.
Might switch cans and guns over time to find best combo if there is such a thing. Time will tell.
I have to get some pics of mine. I did a quick test on my 18" WOA barrel, and got a 1.25" drop straight down with my M4-2000. Very easy to compensate for with the scope.
Jeremy
A good portion of POA/POI shift has to do with the weight of the suppressor, the mounting method, and the length/thickness of the barrel profile
I suspect that the float status of the barrel is a factor too. Just a guess based on a single same can/different gun test I did.
this last part is interesting.
so you suspect a standard profile barrel to have less shift than a lightweight?
I agree with others, longer barrel, pencil barrel, more drop. I have not done a test yet. But looking forward to see how my 14.5 noveske performs.
There wouldn’t be a shift issue if markm and PB knew how to shoot. I guess I am going to have to regulate when I get back to AZ.
Cool to see!
Shift depends on the barrel length and profile, the length, weight and internal design of the can, how concentric the threads/bore are, the ammo, etc. Lots of factors.
The good thing about it is that it is repeatable each time a can is mounted.
You’ll be on the shotgun!
What Jason says (of course) is spot on. I asked what would happen before I tried it and it was exactly as Jason said. I have a DD upper with a pencil barrel (16 inches). The drop at 100 yards is right at 6 inches. But, as has been said, it is perfectly repeatable. Take the can off back to normal, can on, back on, 6 inches low. Pretty easy to work around with my 4 MOA Aimpoint T1. There was almost no zero shift with my old 10.5 416 upper. Of course, that gun has a barrel about as big around as a school janitor’s broom.
GHB
Thanks for this info. ATF has my paperwork on a M4-2000 now.
What mount was on the gun? You think there would be any POI difference between different mounts? Say, 51T Blackout -vs- Brakeout Comp?
Well not an issue. IMHO. Because you don’t change mounts, it stays on the gun. the only variable is the can.