Rifle with suppressor required a new sight adjustment

[Afrikeber]

While at the range today I noticed that without my suppressor I was dead on target but with the suppressor I required a great deal of adjustment both elevation and windage. Is that normal? my setup is an AR platform lower (Engage) with a 300 blk upper having a 11.5 Noveski barrel. Using the AAC 300 blk suppressor and Trijicon scope.

Not liking the fact I have to make such drastic scope changes while swapping suppressor and non suppressor use.

 

[BigDaddy]

While at the range today I noticed that without my suppressor I was dead on target but with the suppressor I required a great deal of adjustment both elevation and windage. Is that normal? my setup is an AR platform lower (Engage) with a 300 blk upper having a 11.5 Noveski barrel. Using the AAC 300 blk suppressor and Trijicon scope.

Not liking the fact I have to make such drastic scope changes while swapping suppressor and non suppressor use.

You don't tell us what a 'great deal' is nor at what range. There is an on going thread about this topic: http://www.mdshooters.com/showthread.php?t=160221&highlight=suppressor

Barrel tuners have been around for a while. Browning has the Boss system. The theory is hanging a weight on the end of the barrel and adjusting it's position lead to better accuracy. A suppressor is the same thing without any adjustment so I am not clear why people are surprised or blame specific manufacturers and models when this happens.

 

[Afrikeber]

You don't tell us what a 'great deal' is nor at what range. There is an on going thread about this topic: http://www.mdshooters.com/showthread.php?t=160221&highlight=suppressor

Barrel tuners have been around for a while. Browning has the Boss system. The theory is hanging a weight on the end of the barrel and adjusting it's position lead to better accuracy. A suppressor is the same thing without any adjustment so I am not clear why people are surprised or blame specific manufacturers and models when this happens.

At 50 yards was off 8" to the right and 6" high from bullseye actually hitting the target frame ......ratchet style AAC762-SDN-6 762mm

 

[BigDaddy]

That sucks. Do suppressors use crush washers? Would adding more help? Just guessing here. Best of luck.

 

[newq]

At 50 yards was off 8" to the right and 6" high from bullseye actually hitting the target frame ......ratchet style AAC762-SDN-6 762mm

From what i have read from Clandestine it would seem you may be getting some baffle strikes. Take it to a gun smith to check for concentricity. Often barrels are threaded for muzzle breaks and flash suppressors but the barrel threading is a hair off center or the adapter may be off a bit as this has been a recent buzz with new suppressors.

 

[swinokur]

Never use a crush washer to mount a can.

 

[clandestine]

AS said, if theres a crush washer STOP and remove it. Its not ok for suppressor use.

You use Shims or nothing.

As far as the POI change its normal. Whoever told you it wont change POI does not know what the hell they are talking about. Shift can vary depending on the can, barrel stiffness, barrel length, ammo, and even temperature/altitude/humidity.

You could be getting baffle strikes. It could be a bad mount, bad can, or just the nature of the combination you are running.

That's all im going to say because Ill only help certain people so much.

 

[Afrikeber]

I think I've figured it out. thanks for help. Much appreciated.

 

[Pinecone]

Quick detach types seem to have more POI change than the Brake Attach or direct thread types.

There is a thread on SH about this, and it seems with the ratchet types, there is a technique to how tight to put them on. I didn't pay much attention, as mine that are coming are direct thread or brake attach.

Also, different brands/models of cans have different POI shifts.

 

[Afrikeber]

Quick detach types seem to have more POI change than the Brake Attach or direct thread types.

There is a thread on SH about this, and it seems with the ratchet types, there is a technique to how tight to put them on. I didn't pay much attention, as mine that are coming are direct thread or brake attach.

Also, different brands/models of cans have different POI shifts.

BINGO! You describe what was occuring. I have a ratchet type and somehow it came loose during firing the rifle yesterday. Went back today and double checked tightness after every shot and I've determined my problem was the suppressor (ratchet style) was loose. Driving tacks at both the 50 and 100 yard targets using sub sonic 174 grain controlled fracturing and 198 grain max expansion Lehigh Defense ammo.

NOTE: After further research there is indeed a problem with the AAC 51T flash hiders and how the ratchet mount AAC suppressors mount on them. there is a "wobble' effect due to the teeth on the ratchet not securing properly on some. I'll be contacting AAC on this. The the last thing I need is baffle strikes.