Holy POI shift Batman !!!

WeiserBucks

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Mounted my 1st suppressor and fired the rifle this morning. 7.75 MOA shift straight down. This is a 9" Ti TOMB mount can on a 24" Proof C.F. barrel. So far accuracy is identical to shooting without the can , but the POI shift seems like a ton compared to what I've read about others experience.

Should I give a shit or just carry on ? This rifle will be suppressed exclusively.
 

diverdon

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Once you dialed in the shift how consistently were you hitting?
 

317millhand

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possibly a threading issue. it would be nice if there was anyway to try a different suppressor on your rifle. that would rule out the suppressor or the rifle threads.
 

WeiserBucks

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Once the shift was accounted for the accuracy is there , about a 3/8ths group at 100 . I got the rifle in a trade and the previous owner fired hundreds of rounds suppressed without any issues so I don't think it's a threading problem.
 

2ndamendfan

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That is a lot. If everything checks out and it is consistent then no big deal. Make note, and adjust accordingly for suppressed/unsuppressed.
 

TheMammoth

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If it’s consistent mounting to mounting then no biggie. Does seem like a lot though.
 

WeiserBucks

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I timed the mount with one shim and applied Rocksett, allowed 24 hrs to cure. Been shooting all morning and so far it's a hammer suppressed, I'm going play with shooting muzzle brake vs can and see if the shift is repeatable.
 
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WeiserBucks

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Took the can off , dialed 7.75 MOA down and fired a group.
7039171

Put the can back on , dialed 7.75 MOA up and fired another 3 rounds.
7039172

This rifle will be suppressed full time, any reason I shouldn't just finalize my suppressed zero and rock on ?
 

Geno C.

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Took the can off , dialed 7.75 MOA down and fired a group.
View attachment 7039171

Put the can back on , dialed 7.75 MOA up and fired another 3 rounds.
View attachment 7039172

This rifle will be suppressed full time, any reason I shouldn't just finalize my suppressed zero and rock on ?
Other than zeroing a little higher and to the right, it looks like you’re gonna be fine
 

101stinfantry

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I have an older GemTech HALO, it has a consistent 3 MOA down, 3 MOA right POI shift. Doesn't matter how I mount it, or what rifle it's on. I just dial the shift and rock on.
 

Rebels010

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Do CF barrel tend have of more POI shift for some reason? Not saying it does, but didn't know if others may have a similar or different experience with their CF barrels.
 

hollowoutadime

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To me, that seems like a lot correction. My cans and rifles are mostly Thunderbeast and AI's with heavier steel barrels. Correction might be .5-1.0" at 100 (or none ).

So I googled and found this thread:

My only misadventure was when a gunsmith didn't properly thread a can and there was a lite endcap strike. Unlike yours, my 2 or 3 rounds didn't group and barrel was cut and re-threaded elsewhere.

I think there's a bore rod you can probably use to check concentrically to the bore, as others said, it's probably fine, just a curiosity.

Had a friend whose AI/MC was timed by a shop with a larger than necessary shim, which caused accuracy issues (brake didn't seat properly). shim replaced. Again, your groups don't suffer.
 

WeiserBucks

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I fired about 75 rounds over the weekend. A few to verify zero and the rest from 400-1120 yards . Accuracy was great, my only misses were blown wind calls .

The shift does seem excessive, but everything else is going as it should at this point.
 

Rebels010

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That’s good. Keep rocking and rolling.

Did you happen to ask the guy you bought it from what POI shifts he had?
 

86alaskan

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may be the carbon fiber barrel. I run an Omega on my christensen carbon 300wm and experience about a 2moa shift. But, like others have said, I never use the rifle without the can, so the shift isn't really anything I'm worried about.