Gunsmith to accurize my LR 308

[ArmyJerry]

Any smiths out there specializing in getting accuracy from these things, I dropped a new 18 inch CBI barrel on this thing sand it still shoots 2+ inch groups, not looking for bugholes just under 1 inch will do, I have tried every ammo available, did normal hand load work up too, still not happy. Any advice appreciated.

 

[ORD]

No offense intended in any way, shape or form...but, first and foremost, are you a sub-MOA shooter with a gas gun? Running your average gasser isn't like running your average bolt gun...any lack of or lapse in fundamentals can quickly open up your groups and lead to accuracy woes.

Additionally, much accuracy can be lost on a gasser (any rifle for that matter) from improper technique/follow-through operating the rifle, from improperly mounted/secured optics, poor fitment of the rifle to the individual shooter, a crap trigger (i.e. - the stock DPMS trigger for example), etc., etc. Furthermore, if you bought a drop-in barrel (from Criterion or otherwise) that was NOT properly fitted to run with your existing bolt (headspaced), then you can lose some degree of accuracy there as well. To those ends, knowing more about your specific setup (other than its an LR-308 with a Criterion bbl) might help in diagnosing the issue.

Getting to the heart of where you are losing accuracy (or where you otherwise aren't optimized to get the most out of the rifle) will go a long way in determining how best to proceed (whether it be stripping the rifle down to its bare receivers and starting over with a custom-built rifle from any number of different AR smiths or going system by system to replace certain parts, etc.).

 

[ArmyJerry]

Yeah I am sub MOA with my other gas gun, RRA 556 with 20 CBI barrel.

 

[EXTREMEPREJUDICE]

GA Precision

 

[Archer762]

There is not a lot to be done with the AR platform. Install new barrel with the proper torque, start shooting. That is assuming you have good scope/rings and no other parts (especially the bolt) out of spec. There is a lot of info out there saying if the bolt is in spec, there should be no headspace issues.

An off-the-shelf LR-308 can usually shoot sub-moa, so there must be something else going on. Did you use a torque wrench to install the barrel, then turn it one more hole to line up the gas tube hole?

 

[ArmyJerry]

I cranked it to 60 ft lbs, then backed off til hole lined up.

 

[ORD]

I cranked it to 60 ft lbs, then backed off til hole lined up.

Not likely the culprit, but instead of cranking to 60ft/lbs then backing it off to line up the gas tube hole...torque it down until the next hole lines up (don't exceed 90ft/lbs...some will say you are ok until 100+ but I don't advise it even though I've removed Armalite nuts at nearing 120ft/lbs) and see if that helps.

Also, as previously mentioned above...what are the other components of your rifle (handguard/trigger/gas system components/stock/buffer/spring/bipod/optics/mount and how you are shooting it for accuracy testing purposes...like bagged, off a bipod, from a rest, etc., etc.)?

If you'd just rather send it off to a smith without doing anything else to it yourself...there's:

1) RW Snyder;
2) GAP;
3) SAC;
4) Specialized Dynamics...the list goes on for miles and miles.

 

[ArmyJerry]

I did the over tq first it popped at a bit over 70 , shot it, got the same groups after I reinstalled using the Tq relief method so I don't think its the tq on the barrel. Thanks for the list,

Diamond rifle langth hand guard FF.

Shooting off a bag,

Lo Pro gas block

Rifle gas tube

Giessel SA trigger

I have had issues getting other guns right but I am at my whits end with this one.