DPMS 308 Rifle Help

[SammyIamToday]

I've had a DPMS LR-308 SASS for a couple of years and it's always shot nigh perfect for me. Recently (last couple of weeks), it's accuracy has gone to the complete opposite of perfect.

It will throw rounds up to a foot off randomly now at 100 yards. I've tried changing the optic out to a known working optic and it was doing the same thing.

I've tried several types of ammo to no effect, it's still horribly inaccurate.

Any ideas on what could cause such a drastic change in accuracy performance in this rifle? I'm at a loss for what to do now, and need help badly.

 

[Freedom_fighter_in_IL]

You changed optics, but did you also change rings and rail? Have you checked the torque on the rail? If it was an all of a sudden thing then more than likely it has something to do with your optics. If you still have your iron sites, try a few groups without optics and see if you still have the problem. If so, then it could be any number of things.

 

[madcratebuilder]

Inspect the crown for possible damage. Inspect the barrel nut and confirm it's torqued to spec, about 50ftlbs for the .308 AR's. I would remove the optics and test with iron sights. Next I would run some copper solvent through the bore, scrub it good and clean.
Report back.

 

[Michael R.]

your rail could be clamping down on the barrel and it could affect the barrels harmonics. take the rail off and then shoot it.

 

[SammyIamToday]

When I changed optics, it was to a different mount. So basically, I have a Trijicon Accupoint 3-9x that usually lives on there via a Larue Mount. I changed to a Trijicon Accupoint 1.25-4x that lives on my DPMS 308 AP4 via a larue mount.

I do have some iron sights, so I will test those next.

As well as the other tips. Thanks folks!