POI Shift Suppressed

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SouthernSlammed

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So, I wanting to see some others numbers regarding POI Shift when shooting suppressed.

Now as I understand it, this is the shift in the bullet from shooting unsuppressed to going suppressed. Correct me if I'm wrong.

So, when I was out this weekend I was really paying attention to where my bullet was hitting and not just adjusting my scope for the suppressor. Unsuppressed the gun is dead bullseye. What I was a little shocked to see was that I have a 6" shift zero low putting the suppressor on.
I have heard just a little about POI but never paid attention to what kind of shift people were having. I just wanted to get some idea of what others were experiencing.

SETUP:
Gun: Ruger M77 Varmint Target, 26" not threaded from factory
Scope: Vortex Crossfire II 6-18x44 AO
Ammo: ZQI 7.62x51 147g
Can: Dobbs Defense ARC30
Position: Shooting from lead sled
Distance: 100yds
20170212_114955.jpg

per the internet... if you have 8" POI Shift, then you need to check out your gun.
Is 6" really pushing it and need to have it looked at?
 

dial1911

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Ha- I will post more on this later, but my POI understanding is the same as yours... difference in impact between can on/off.

My AR carbine with a SPECWAR 5.56 also shoots 6" low with the can on it. That's the reason I dumped some fairly nice Troy sights- they didn't have rear elevation adjustment. I needed a knob similar to the carry handle sight to be able to quickly and easily adjust for the POI shift.

I've never hear you need to check your gun due to the amount of shift. It's got to do with barrel harmonics and possibly some other things. Some of the best groups I've ever seen where shot with a sack of lead hung over the barrel- dampens out the harmonics and makes the gun shoot really repeatably (provided everything else is same-same).
 
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boss_hawg

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i get pretty significant poi shift out of my specwar 556 and 762. i don't think these cans were designed with poi shift minimization in mind.
 
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Cudruln

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The can is junk. I will pay for shipping, pm sent with my address.



Seriously though POI shift is normal when shooting suppressed (at least from what I have heard). With that being said at the 6" drop are you still hitting dead on or does it spread out?
 

PewPewPewCo

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The Dobbs can is fairly heavy, like the Specwar, so yea its going to shift POI since its extra weight on the barrel alone, additionally the pressure effects on the bullet.
 
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EugenFJR

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It's nothing out of the norm... When we were doing the 110 SASS KAC rifles we saw a about a six inch shift from shooting suppressed, vs non suppressed at about 300 yards... And, if I remember this right... They were all 6 inches to the left, from the non-suppressed zero, @ 300 yards....
 
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boss_hawg

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It's nothing out of the norm... When we were doing the 110 SASS KAC rifles we saw a about a six inch shift from shooting suppressed, vs non suppressed at about 300 yards... And, if I remember this right... They were all 6 inches to the left, from the non-suppressed zero, @ 300 yards....

both of my specwars shoot low and to the left (penis joke in there somewhere) vs. non-suppressed zero.

my solution? i determine which rifles i want to shoot suppressed only and zero to the suppressed position.
 
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SouthernSlammed

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The can is junk. I will pay for shipping, pm sent with my address.
:rofl:


Seriously though POI shift is normal when shooting suppressed (at least from what I have heard). With that being said at the 6" drop are you still hitting dead on or does it spread out?

I was reading 1-2 MOA was typical, but then thats the internet/marketing. Dead on, 6" low!
 
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SouthernSlammed

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The Dobbs can is fairly heavy, like the Specwar, so yea its going to shift POI since its extra weight on the barrel alone, additionally the pressure effects on the bullet.

Curious if extra support towards the end of the barrel would effect POI.
 

SouthernSlammed

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It's nothing out of the norm... When we were doing the 110 SASS KAC rifles we saw a about a six inch shift from shooting suppressed, vs non suppressed at about 300 yards... And, if I remember this right... They were all 6 inches to the left, from the non-suppressed zero, @ 300 yards....

6" @ 300 you're talking 2" at 100.
 

SouthernSlammed

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both of my specwars shoot low and to the left (penis joke in there somewhere) vs. non-suppressed zero.

my solution? i determine which rifles i want to suppressed only and zero to the suppressed position.

Low and left, is a good day... hanging penis that is!!!

I would probably only continue to shoot this gun suppressed, just because it is better! But hopefully to take it hawg hunting and knocking'em down at a nice distance.
 

KGmade

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Quite a few factors go into POI shift with a suppressor. Some of it is as simple as hanging a bunch of weight at the end of the barrel and flexing it down a few minutes, some of it is how accurate the threading of the rifle is, some if it is how accurate the QD system is, and some of it is the baffle geometry.
Group size can change too. Sometimes the can helps the barrel harmonics and tightens up the groups
 
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EugenFJR

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Quite a few factors go into POI shift with a suppressor. Some of it is as simple as hanging a bunch of weight at the end of the barrel and flexing it down a few minutes, some of it is how accurate the threading of the rifle is, some if it is how accurate the QD system is, and some of it is the baffle geometry.
Group size can change too. Sometimes the can helps the barrel harmonics and tightens up the groups

I'm really thinking about pulling the trigger, and getting one of your 10/22's BTW...
 

Laufen

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Low and left, is a good day... hanging penis that is!!!

I would probably only continue to shoot this gun suppressed, just because it is better! But hopefully to take it hawg hunting and knocking'em down at a nice distance.
Maybe chop and re-thread the barrel to stiffen it? You have a lot of barrel to work with. Maybe take it down a few inches.
 
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Laufen

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May just contact Ruger and advise that their Target Barrel is sagging!
I remember one trick I used to use was to bed the underside of the barrel a couple inches where it meets the receiver. I just used a fiberglass bedding kit, but it seemed to really help. It was particularly helpful on longer barreled rifles since it gave some extra support and would reduce sagging.

Maybe give that a try.
 

PewPewPewCo

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I remember one trick I used to use was to bed the underside of the barrel a couple inches where it meets the receiver. I just used a fiberglass bedding kit, but it seemed to really help. It was particularly helpful on longer barreled rifles since it gave some extra support and would reduce sagging.

Maybe give that a try.
you pack your shit up and leave with that talk of un floating the barrel. We don't welcome your kind here
 
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