point of impact shift?

[blaster]

I have had a .22 suppressor for a few years now. (GemTec Outback II) when I put it on any of my host firearms it causes the bullet to hit about 2 ft. low & to the left. I am using D.A.Q. threaded adapters on the hosts (Ruger std. pistols & 10/22 rifle) I have a suspicion that the adapter is causing this but not sure. my question is - will the .30 Omega I am waiting for also shift the P.O.I. even though it is a direct thread on can? or do all suppressors cause the P.O.I. to shift?

[Dr.Phil]

Almost all suppressors have POI shift.
This is due to changes in barrel harmonics, barrel droop due to the additional weight at the end of the barrel, and velocity changes due to free bore boost.
Not a big deal, just need to make note of it in your "dope book" and correct appropriately.

[JeffWard]

At what yardage, and how long/thick is the barrel on the 10/22".

Long/thin barrel profiles droop and "whip" more with the weight of a suppressor on the end. Thick/stiff/short barrels droop and whip less. Lighter cans cause less droop.

If you watch a rifle barrel in super slow-mo, you can see it flex as the bullet passes down the barrel. This is why F-Class rifles fired at 100 yards often run 1.25" thick their full length. They are 26"+ long, to achieve 1000+ yard velocities.

There is always a trade off for length/velocity, and for stiffness/weight.

My precision 308 rifle has a 16.5" barrel, and VERY stiff/thick. I chose that length to shoot suppressed. I'm giving up velocity to reach out past 700-800 yards, but I gain stiffness, harmonics, and less weight.

JW

[rimshaker]

I have had a .22 suppressor for a few years now. (GemTec Outback II) when I put it on any of my host firearms it causes the bullet to hit about 2 ft. low & to the left. I am using D.A.Q. threaded adapters on the hosts (Ruger std. pistols & 10/22 rifle) I have a suspicion that the adapter is causing this but not sure. my question is - will the .30 Omega I am waiting for also shift the P.O.I. even though it is a direct thread on can? or do all suppressors cause the P.O.I. to shift?

Is this what you're using?

http://www.muzzlecouplings.com/muzzle_couplings.htm

[blaster]

yes, thats the coupling. are you familiar with them?

[rimshaker]

That is definitely not the best way to attach a can. Much less expect minimal POI shifts. That adapter is definitely why you're getting huge shifts.

Get your barrels properly threaded concentric to the bore, and you'll get much better results. Most likely zero POI with 22LR.

[blaster]

thanks, thats what I expected.

[plant.one]

my sparrow is direct thread. poi shift is almost immeasurable. i do have a .920 heavy barrel though.

the only scope adjustments i make are 8 clicks to go from subsonic's to 1260 ammo.