First time posting here. Long time follower! Recently received my first rifle suppressor. I sighted the weapon in suppressed as I plan to hunt the majority of the time with it on. While shooting at 100yds unsuppressed I noticed that my groups were roughly .75 Left and 2.5 low. From what I’ve read most individuals POI shifts upward while unsuppressed due to less weight at the end of the barrel. Has anyone else noticed a similar change? Any way to explain this? I just can’t seem to wrap my head around why the bullets landed low.
Questions regarding suppressed POI shift
- Thread starter Cccook8
- Start date
It's simple really. You are hanging a weight off the end of your gun.
Also double check your mount. If it's not perfectly square it can throw off shots. If needed use a shim kit. Never ever use a crush washer. If the barrel itself is not cut perfectly square you might need to get it fixed.
If the muzzle device needs to be timed double check that too. I made that mistake on my first can (not timing my muzzle device when it was clearly in the instructions to do so) and that increased my POI shift a little bit. After removal and reinstallation it went to about a 1" shift.
If your can is a QD type that has some play in it or that don't lock up tight then this kind of shift is normal. More play=more shift.
The main thing is if the shift is repeatable. Cans that can be mounted in different orientations are not my favorite because there is no way to really ensure the same mounting position each time.
Also double check your mount. If it's not perfectly square it can throw off shots. If needed use a shim kit. Never ever use a crush washer. If the barrel itself is not cut perfectly square you might need to get it fixed.
If the muzzle device needs to be timed double check that too. I made that mistake on my first can (not timing my muzzle device when it was clearly in the instructions to do so) and that increased my POI shift a little bit. After removal and reinstallation it went to about a 1" shift.
If your can is a QD type that has some play in it or that don't lock up tight then this kind of shift is normal. More play=more shift.
The main thing is if the shift is repeatable. Cans that can be mounted in different orientations are not my favorite because there is no way to really ensure the same mounting position each time.
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Thanks for the reply’s. Im chalking it up to barrel harmonics.
All I’ve read previously stated most POI shift would put your suppressed groups lower than your unsuppressed groups.
I’m running a 300wsm with a direct thread can. My unsuppressed groups are 2.5” lower. Just find it hard to believe the suppressed groups are that much higher with 10oz of weight extra at the end.
All I’ve read previously stated most POI shift would put your suppressed groups lower than your unsuppressed groups.
I’m running a 300wsm with a direct thread can. My unsuppressed groups are 2.5” lower. Just find it hard to believe the suppressed groups are that much higher with 10oz of weight extra at the end.
I agree with above. As long is it’s repeatable who cares. One thing to watch, since hunting with it, is the first, cold bore shot suppressed differing from the next suppressed shots. Some report TBAC cans “never” doing this etc and I can’t confirm that. Also hard to believe but whatever.
I know my SiCo Omega is about 1/2-3/4” high on the first shot at 100 yd in both my .308 and 6.5 prc with 24” barrels. Other guns I haven’t paid as much attention so can’t comment.
I know my SiCo Omega is about 1/2-3/4” high on the first shot at 100 yd in both my .308 and 6.5 prc with 24” barrels. Other guns I haven’t paid as much attention so can’t comment.
That is a bit weird but not at all impossible. I misread. I thought you were hitting low. Not sure what type of can and/or muzzle device (if any) is involved.
I would suspect it has something to do with misalignment or how the can is timed on the gun when fully mounted up. If you didn't clean up the threads and shoulder really good before mounting everything up there could be a tiny piece of debris pushing the alignment slightly out of place. I've seen that happen.
Just as a precaution maybe undo everything and do a clean install again and see if that helps anything.
Rifle was build by TS Customs. It’s proved to be a shooter for sure. Rifle has shown to be repeatable between suppressed/unsuppressed. Was mostly looking to see if anyone else has had similar shift and maybe some insight on the physics of it. Thanks for all the inputs guys!
have you measured velocity with and without the suppressor?
also have you tested poi shift with the lightest vs heaviest projectiles?
as already noted, the important thing is that it is repeatable and consistent with or without.
barrel profile and length is also going to be a factor, which goes back to harmonics and velocity,
also have you tested poi shift with the lightest vs heaviest projectiles?
as already noted, the important thing is that it is repeatable and consistent with or without.
barrel profile and length is also going to be a factor, which goes back to harmonics and velocity,
Rifle is a 300wsm with a 24” proof research carbon Sendero profile. I figured the barrel would be pretty stiff with little POI shifts. I’ve tried 180-210gr factory ammo with pretty similar results.
Haven’t had a chance to chronograph it yet. Working on getting a chrono from a buddy. Should be interesting to see the velocity differences.
Haven’t had a chance to chronograph it yet. Working on getting a chrono from a buddy. Should be interesting to see the velocity differences.
It's not weird at all to have a brake, tuner, Magnetos speed, or can to impact higher than your naked barrel.
