Are these results standard for the BCM SS410 barrels?

[MitchK]

Here's my 20" bcm rifle. I shot this group last week. 77 smk with 23.7 gr of varget

[mtdawg169]

Sorry, should have posted that earlier.



Upper is a complete factory BCM upper receiver group. It features their 18" SS410 barrel, Bootleg Inc. pic-mod handguard, BCM Gunfighter Comp, BCM gunfighter charging handle, BCM complete bolt carrier group.

Lower receiver is a complete factory BCM lower receiver group with intermediate (a5) buffer system. Scope is mounted via American Defense Manufacturing recon scout mount.

First thing I would do is to ditch the comp and install a plain jane A2 or Smith Vortex. I'd try it with the A2 first to see if the comp was causing any issues.

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[Pappabear]

Yea something is way wrong. That is a greT barrel. I would double back on mount and scope. See if you have a buddy that has another optic. Throw it on

You could shoot a better group with that BCM barrel with a RDS or ACOG if you have one. I had a similar problem on a bolt gun with a Nikon scope. Threw on a ACOG and shot a much much tighter group. Try a different mount and optic. Before you start tearing the gun apart. The barrel will shoot sub moa all day long if it's in the norm. I suspect it is. Even if you got a lemon, it would shoot better than that.

Good luck.

PB

[Kain]

I expected to click on this thread and see someone bitching about a barrel not liking a certain load, have an RRA barrel like that. I did not expect this or that hte OP would have covered so many loads. I guess my assumptions got me good this time.

Haven't played with BCM's stainless barrels. YET. But, considering I have printed grouped better than that with a 4x TAO1NSN ACOG and milspec trigger off the magazine with a BFH barrel with Prvi 75gr and Hornady steelmatch 55gr and 75gr. And by better I have had a few, when I was really on that were quarter sized, and more than 3 or 5 shot. I would say something is up somewhere the barrel, optic, or mount. I await further information to see what fixes this and gets the OP back to where he should be group wise.

[sidewaysil80]

Thanks so much for confirming my suspicions.

1. First thing I'm going to do is explain my situation to Vortex and see if they're willing to take a look at the scope; so I can at least rule that out.

2. In the meantime I'll see about finding/using a different mount and optic and see if that helps. That way I can rule out the mount.

3. If nothing else works I'll reach out to BCM and make sure they will still warranty the upper if I replace the compensator with an AAC brake I have available. That will allow me to rule out the muzzle device.

4. If all else fails I'll send BCM all of my target sheets and the upper and see what they say.

If anyone else has any other suggestions or advice I look forward to hearing it!!!

[Joe Mamma]

After setting it to optimum eye relief I used a small level on the receiver and small level on the top of elevation cap. After ensuring they were even I tightened the mount gradually at the bottom rings, then top rings, torqued the bottom rings to 25-30 in/lbs, then torqued the top rings to 25-30 in/lbs using a wheeler fat wrench. I followed the instructions supplied with the ADM mount.

You may have overlooked something. If your ADM Recon mount has QD throw levers ( I couldn't tell if it does frrom your picture), check if the mount is loose on your rail. I had an issue with that happening with an ADM Recon-X mount. I think the screws (attached tot he levers) stretched or something.

Joe Mamma

[Onyx Z]

Did you remove copper or just clean the carbon out?

[sidewaysil80]

Did you remove copper or just clean the carbon out?

Just the copper using Hoppes 9, should I run some sweets or something through it? I've never used anything other then Hoppes 9 for cleaning barrels, but I'll look into it. Do you run the sweets through a couple times and then run Hoppes through it like normal?

You may have overlooked something. If your ADM Recon mount has QD throw levers ( I couldn't tell if it does frrom your picture), check if the mount is loose on your rail. I had an issue with that happening with an ADM Recon-X mount. I think the screws (attached tot he levers) stretched or something.

Joe Mamma

I'll double check that tonight, thanks for the tip!

[Eurodriver]

I wouldn't even bother with cleaning copper out of the barrel. Those groups are too big for a brand new barrel.

I would shoot the gun with another proven scope, and if the results are the same I would send it back to BCM.

[MegademiC]

Thanks so much for confirming my suspicions.

1. First thing I'm going to do is explain my situation to Vortex and see if they're willing to take a look at the scope; so I can at least rule that out.

2. In the meantime I'll see about finding/using a different mount and optic and see if that helps. That way I can rule out the mount.

3. If nothing else works I'll reach out to BCM and make sure they will still warranty the upper if I replace the compensator with an AAC brake I have available. That will allow me to rule out the muzzle device.

4. If all else fails I'll send BCM all of my target sheets and the upper and see what they say.

If anyone else has any other suggestions or advice I look forward to hearing it!!!

I would throw some irons or any other known-good sight and try it out before anything else. My buddy has that same barrel and 5 shots should be 1 inch or less. 3 shot groups of handload can be covered by a dime most of the time.