Recommendation on upper for solid fit to RRA lower

[Stubb]

I recently rebuilt a cheap RRA carbine with some choice components: Centurion Arms midweight barrel, LaRue handguard, Giselle DMR trigger, Aimpoint ML3, etc. A nagging issue is the play between the upper and lower receiver—the rifle rattles like a cheap toy. The upper receiver moves side to side as well as up and down.

A check of previous threads shows that some folks have used epoxy to shim the parts, but this doesn't seem like it would help with the side-to-side wobble.

My LaRue upper locks into the RRA lower like a bank vault but is priced accordingly. I understand that LaRue builds their uppers to maximum specified size. Are there any other uppers that would likely provide a similar fit?

—Andreas

 

[JMC]

Re: Recommendation on upper for solid fit to RRA lower

Did you look into Rock River also? I think I heard something that said that their uppers are on the thicker side to allow for a tighter fit. I can speak from experiance with them though as I haven't used them. Maybe give them a call. Or otherwise maybe try Brownells?

Good Luck
JMC

 

[Zebra644]

Re: Recommendation on upper for solid fit to RRA lower

Spikes Tactical,Rockriver, Bushmaster which is now owned by Remington by the way, DMPS, STAG Arms, Smith & Wesson which is also made by Stag & Anvil Arms, Then you start getting into the pricy ones like LaRue, Novenske,Colt. Have you looked into putting a wedge in it. It is supposed to help with fit issues, and they are only a couple of dollars, you can find them at midway usa and brownells. They sit behind the rear take down pin and where the buffer tube is.

 

[ORD]

Re: Recommendation on upper for solid fit to RRA lower

Skip the rubber/nylon wedges that go behind the rear takedown pin. They do get rid of the "wobble" or "wiggle" between the upper/lower on some rifles. They have to be trimmed down to fit in most RRA lowers because the shelf in the RRA's is a little higher than some others.

BUT...more importantly, the accu-wedges/receiver wedges actually work opposite to what they should do because they force the upper/lower apart and allow them to flex/move under recoil. One may actually worsen your side-to-side movement problem.

If you want to stop improper fit between your upper/lower, take a look at the JP Enterprises Tensioning pins. They replace the rear takedown pin and offer a much better option to cramming a rubber wedge into your lower! They pull the upper down and back onto the lower receiver making the receiver fit together tightly.

 

[338LM]

Re: Recommendation on upper for solid fit to RRA lower

Every Rock River rifle I own/have owned is/was a nice and tight upper to lower fit.

 

[Stubb]

Re: Recommendation on upper for solid fit to RRA lower

Thanks for all the suggestions. The rifle uses a RR upper and lower, albeit ones from nearly ten years ago. The JP pins look pretty slick despite requiring a screwdriver to disassemble the rifle. I'll likely order two or three different uppers and keep the one that fits.

—Andreas

 

[LoneWolfUSMC]

Re: Recommendation on upper for solid fit to RRA lower

Epoxy will help eliminate the side to side as well since it will flow AROUND the bottom of the lug if you do it correctly.

HOWEVER, I do not recommend it especially if it's a fighting rifle.

Keep in mind thousands of Marines (including myself) have qualified expert out to 500 yards with loose fitting rifles.

 

[randyk338]

Re: Recommendation on upper for solid fit to RRA lower

I had the same problem with a stag arms lower, the JP pin solved all my problems.