Eliminating play in upper and lower receiver

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[ARCHIVED THREAD] - Eliminating play in upper and lower receiver

Posted: 4/21/2016 1:55:33 PM EDT

Does anybody know if there is a way to modify a lower receiver to have a tension screw installed like the ones found on the Aero Gen 2 lowers. I have a Rock River Arms upper/lower that has a lot of play

Posted: 4/21/2016 3:09:34 PM EDT

[#1]

Yea, drill and tap from under the pistol grip for, say, a 1/4-20 nylon tipped set screw which you can get from Mcmaster.

Or there's this: http://www.wheeldiamond.com/nationalmatchshim.htm

I just got a bunch, but unfortunately on the particular upper I wanted to use it the most the cutout it fits into is too deep, so I may be rebuilding it with a different upper receiver I have lying around.

Posted: 4/21/2016 3:12:35 PM EDT

[#2]

Easy way

Posted: 4/21/2016 4:40:52 PM EDT

[#3]

How in the world did you get an RRA receiver set that has play. Did you get it new? Generally RRA lowers are cut such that you have to hammer the upper on with a rubber mallet to get them together.

Posted: 4/21/2016 5:12:04 PM EDT

[#4]

I use varmintlight xshims. They do they job without breaking like the o rings.

Posted: 4/21/2016 7:10:48 PM EDT

[#5]

Quote History

Quoted:
How in the world did you get an RRA receiver set that has play. Did you get it new? Generally RRA lowers are cut such that you have to hammer the upper on with a rubber mallet to get them together.

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I fully agree.
I stupidly SBR'd a RRA lower. Yowsah, I have to fight every upper I try to fit on it.

Posted: 4/22/2016 12:31:25 AM EDT

[#6]

Quote History

Quoted:
How in the world did you get an RRA receiver set that has play. Did you get it new? Generally RRA lowers are cut such that you have to hammer the upper on with a rubber mallet to get them together.

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This is a true thing. fortunately they settle in pretty quickly and just stay a nice fit.

Posted: 4/22/2016 12:49:26 AM EDT

[#7]

Quote History

Quoted:
How in the world did you get an RRA receiver set that has play. Did you get it new? Generally RRA lowers are cut such that you have to hammer the upper on with a rubber mallet to get them together.

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I had the upper and lower NP3 by Robar. I don't know if this is what gave it so much play? Yes, I purchased it new and have only shot less than 100 rounds with it.

Posted: 4/22/2016 3:02:19 AM EDT

[#8]

O-rings break. Accuwedge's loosen up over time. They are all "band-aid's" to make you FEEL better. It is not a matter of function (and actually could be more harm than good if a loose chunk of rubber goes renegade in your lower). Just accept the "wiggle", it doesn't hurt anything.

Posted: 4/22/2016 7:43:03 AM EDT

[#9]

Quote History

Quoted:
O-rings break. Accuwedge's loosen up over time. They are all "band-aid's" to make you FEEL better. It is not a matter of function (and actually could be more harm than good if a loose chunk of rubber goes renegade in your lower). Just accept the "wiggle", it doesn't hurt anything.

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Or add the tension screw. Or a Demon Tactical takedown pin if it bothers you enough.

Posted: 4/22/2016 9:36:30 AM EDT

[#10]

guys, I appreciate all the advice.

Posted: 4/22/2016 9:56:14 AM EDT

[#11]

The best way I've seen is an Upper Tension Screw. You would need to drill & tap threads to install, but should be simple to do with a drill press, vice and lube.

Posted: 4/22/2016 11:42:59 AM EDT

[#12]

Quote History

Quoted:

This is a true thing. fortunately they settle in pretty quickly and just stay a nice fit.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
How in the world did you get an RRA receiver set that has play. Did you get it new? Generally RRA lowers are cut such that you have to hammer the upper on with a rubber mallet to get them together.

This is a true thing. fortunately they settle in pretty quickly and just stay a nice fit.

I've built on five RRA lowers. They are snug but end up just about right.
Never seen one that was loose.

Just shoot it.