POI shift and Accuracy with suppessor

Discussion in 'Firearms' started by gunsmoker, Nov 4, 2018.

  1. gunsmoker

    gunsmoker Lawyer and Gun Activist

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    66404768-55D4-4A5A-AF45-9FAEA66E9BF7.jpeg E7DBE1D8-F820-4B8E-94E9-FA7DF890210F.jpeg

    I tested my .22 LR silencer for point of impact shift on my Ruger 10/22 rifle some 10 years ago. I vaguely remember that the result was that the point of impact shift seemed to be there, but very minor. Only one minute of angle --which was less then the variation I would get when switching brands of ammo.

    And I found that the silencer didn't impact accuracy at all.

    I eventually replaced my 18" threaded Ruger barrel with a 22" Green Mtn. threaded barrel.

    Yesterday I tested the 10/22 again. I used CCI Subsonic HP ammo.

    5 rounds prone at 50 yards, suppressor on muzzle.

    Got a 2.5" group.

    Took the can off, screwed on the M16A2 bird cage I use instead of a thread protector, and shot a sub-inch group.

    Same position, prone.
    Same distance, 50 yds.

    There wasn't any noticeable point of impact shift. Both groups were a couple inches high and about an inch and a half left of center. That could be due to the type of ammo I was using and the wind conditions. Also I think my rifle has been sighted-in for 100 yards so it should be high if I'm firing at 50.
     
  2. Wegahe

    Wegahe NRA Instructor

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    If you remember there was 0 POI difference on my 308 with or without the suppressor. I really don't thing the suppressors make much of a difference at short ranges if any.
     

  3. moe mensale

    moe mensale Well-Known Member

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    Barrel harmonics more pronounced with a suppressor?
     
  4. Wegahe

    Wegahe NRA Instructor

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    I'm not sure on the .22. On my 26'' heavy barrel .308 it didn't make any difference.
     
  5. moe mensale

    moe mensale Well-Known Member

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    GS hasn't mentioned what type of barrel he's now using except that it's 4" longer. Is it a heavy barrel, a pencil barrel, a composite barrel, etc? What suppressor (length & weight) is he using?
     
  6. gunsmoker

    gunsmoker Lawyer and Gun Activist

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    All .22 LR suppressors are about the same, aren't they?
    Same size. Same weight. Same effectiveness if ysed on the same gun with same ammo.

    Anyhow, the longer barrel is a fade-fluted Green Mountain barrel. It's basically a slender barrel like the factory Ruger barrel, except it's a little bit fatter for the first 12 inches or so. The grooves /flutes milled into it are supposed to stiffen it.
     
  7. gunsmoker

    gunsmoker Lawyer and Gun Activist

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    255B163F-E17F-42AF-9F05-CAD0AE8B10CE.jpeg Pic of this 10/22 in a Hogue Overmolded stock.

    Which reminds me, I do not know what stock I had on my rifle when I tested it back when I first got my suppressor more than 10 years ago. Perhaps a different stock is affecting barrel harmonics and the weight of the suppressor is unfavorable to those harmonics while the weight of an M-16 birdcage suits it fine.
     
  8. moe mensale

    moe mensale Well-Known Member

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    I don't know. I've only used center fire suppressors before and the lengths and weights can vary quite a bit. A couple of ounces, an inch or two, can give different results.

    Have you found any online test results for that barrel with and without suppressors? That might give you some insight.