Barrel doesn't like the suppressor

[308sako]

First time I have encountered this. Built an 18" upper and the rifle appears to only want to shoot when the suppressor is not mounted. I have used this AAC SPR-M4 on four different rifles/SBR's and had no issues... comments please.

[G27RR]

What do you mean by only wants to shoot when the suppressor is not mounted? Cycling issues, accuracy issues, something else?

[308sako]

What do you mean by only wants to shoot when the suppressor is not mounted? Cycling issues, accuracy issues, something else?

Accuracy issues

[zandander]

Repeatable? Or are the shots going everywhere?

[DirtDiver06]

Check the torque on the muzzle device

What barrel profile you running?

[Iraqgunz]

How about providing some more details so we can help you out?

[markm]

Sounds like you may need to develop a load for the barrel with the can mounted. If the barrel shoots without the can, then their is probably a load that will make it shoot with the can mounted.

[TAZ]

Need more details on the parts. If the rifle shoots well without the can then it's doubtful that the assembly can be too FUBAR. Based in the scant info Id say either the added weight on the barrel is messing with the harmonics and you'll need to develop a load for that combo like Markm stated. Another thing might be your MD not being concentric with he bore. Not enough out of whack to make a difference when the projectiles are going through he MD, but add the extra few inches of the can and you could be getting too close to a baffle or endcap. Is this MD the same kind and manufacturer as with all other rifles?

[markm]

Also.... If the can locks up tight/isn't rattling on the end of the barrel.... I think a load can be made for it.

[308sako]

I'm not looking to trash the manufacturer so please don't take the parts list as an effort to do anything other than for the purpose of this evaluation.

Mega billet set upper and lower.
Mega 18" barrel
AAC 51T miter mount and SPR-M4 suppressor
Giessele HiSpeed match trigger
MI Gen 2 SSI Ultra light
Noveske Switchblock
BCM FA bolt and carrier

Ammunition tried has been 50 grain, 55, 60, 69 & mostly 77 Sierra MK's with XBR in 1/10 grain increments.

Well off to the range to try one last time before a phone call to Washington state. I'm going to try switching out the bolt carrier group on a wild goose chase.