Confirm Action

Are you sure you wish to do this?

Confirm Cancel
Member Login
Site Notices
10/20/2017 1:01:18 AM
9/22/2017 12:11:25 AM
Posted: 9/18/2005 3:29:51 PM EDT
When building a new rifle with upper and lower recievers from different manufactures....how do people tighten the fit between the two up? (without and accuwedge) like those custom rig builders...
Chances are when I put an Armalite upper with a RRA lower there will be some wobble but if I want to build a match gun or DMR, want to get the best fit.
Link Posted: 9/18/2005 5:27:06 PM EDT
Actually, whether you buy upper and lower receivers from the same manufacturer or mix and match, you won't have a perfect fit in either case (unless you order a "matched" set, in which case someone tries several pairs of receivers and picks out a reasonably close fit/match. Lowers are all machined to the same spec's as are all uppers, so theoretically, they should all be able to fit together. In reality, most matchups have a little bit of play (occasionally, they are too tight, and won't fit together without a little work).

Someone with more experience/expertise might correct me, but I believe the best way to tighten up an upper/lower combo is to use a tensioning takedown pin, available from JP Enterprises.
Link Posted: 9/18/2005 6:24:53 PM EDT
Read all about it!


Armalite's Tech Notes are a wealth of knowledge... read them.

"There is an intuitive belief that a tight fit between the upper and lower receivers is essential to accuracy, and that loose fit is bad. Oddly enough, this is untrue."


"Receivers will normally exhibit a certain amount of looseness. This is normal and will not affect accuracy. Shooters may reduce the movement by insertion of a small amount of material between the receivers to improve the feel of the rifle, but it won’t improve accuracy."
Link Posted: 9/18/2005 6:26:56 PM EDT
The easiest way, and as effective as anything else is to use an Accuwedge. This is a small orange or red rubber wedge that fits into the back of the lower receiver.

There are other ways, but none work better or improve accuracy. They just remove the rattle.
Top Top