Is there anything that can be done to take the play out of an upper and lower receiver other than getting the shims (accu wedge I think its called). I have an upper and lower than have a little wiggle that I want to be a solid lock up. Thanks in advance
-
Having trouble using the site?
Contact support
Gunsmithing upper and lower receiver play
- Thread starter Munson
- Start date
I've found on quite a few builds that some takedown pins are a bit smaller than others and cause some play. Trying a different set of takedown pins sometimes works for me in taking out the play. I tried the accuwedge once and really didn't like it. I've actually ordered in a different receiver a couple of times to get a receiver that mated better with the upper I had.
--Wintermute
--Wintermute
You can drill and tap the lower receiver vertically at the rear takedown pin for a nylon tipped setscrew ala POF. That is really only practical for a rifle that won't see field stripping often though and you need a punch or similar to break the rifle down. Think match rifle.
The accuwedge is more practical for a normal use rifle.
I will agree with Graham, you think you want a total zero play upper/lower but in reality unless it is a match rifle, you don't.
The accuwedge is more practical for a normal use rifle.
I will agree with Graham, you think you want a total zero play upper/lower but in reality unless it is a match rifle, you don't.
Last edited:
There are all sorts of "gadgets" that can help to remove the play between your upper and lower, but frankly...aside from perhaps being a little annoying...it is NOT hurting anything so leave it well enough alone.
As for the "gadgets"...if you simply MUST @#$% with it...the accuwedges and like products are crap. They force the upper and lower APART on a flimsy piece of rubber/polymer, and having witnessed one break in the past and creep its way into the FCG, you don't want that headache. They are purely gimmicky BS for suckers who buy the marketing crap about allegedly "enhancing accuracy," blah, blah, blah when in fact, they don't have any meaningful impact on improving the rifle whatsoever.
JP Rear Tension Pins...these actually pull the upper/lower tighter together and remove basically ALL play between them. The problem is that they make breaking down the rifle a royal PITA, requiring tools instead of just pushing out the takedown pin. If you don't need to disassemble the rifle quickly and you really MUST eliminate the annoyance of the rattle...the JP pins work well, but they are unnecessary and costly (at ~$40) and can cause damage to your receiver and the pin itself if you don't use them properly.
As for the "gadgets"...if you simply MUST @#$% with it...the accuwedges and like products are crap. They force the upper and lower APART on a flimsy piece of rubber/polymer, and having witnessed one break in the past and creep its way into the FCG, you don't want that headache. They are purely gimmicky BS for suckers who buy the marketing crap about allegedly "enhancing accuracy," blah, blah, blah when in fact, they don't have any meaningful impact on improving the rifle whatsoever.
JP Rear Tension Pins...these actually pull the upper/lower tighter together and remove basically ALL play between them. The problem is that they make breaking down the rifle a royal PITA, requiring tools instead of just pushing out the takedown pin. If you don't need to disassemble the rifle quickly and you really MUST eliminate the annoyance of the rattle...the JP pins work well, but they are unnecessary and costly (at ~$40) and can cause damage to your receiver and the pin itself if you don't use them properly.
I have been told (by a reputable gunsmith) that the best way to mate AR receivers is to bed them to each other. I'm not sure of the exact process (seems like it would be a little more involved than bedding a bolt action).
I never had it done though, because on my 16" AR15, it seemed like a wasted effort, and on my 20" Mega MATEN, the receivers mate so well it's not an issue.
I never had it done though, because on my 16" AR15, it seemed like a wasted effort, and on my 20" Mega MATEN, the receivers mate so well it's not an issue.
It wont impact your shooting, a little play is fairly normal, unless we are talking about a 3-5mm play.
It's easy. Go get a lid from a parkay tub and cut a shim with some skizzers.
Lay it between the U/L right in front of the FRONT take down pin. This gives you leverage to squish it and get the bugger back together.
Then trim the stuff that poops out between the two.
When I was an active duty Marine I did this to every issue M16A2 I ever shot during Intramurals, Division Matches, etc.
Worked great. Make a few and keep in your kit as they do get lost/wear out, etc.
Screws drilled and tapped work as well, however know that your U/L are made from AL. Even 7075 is going to peen over time. Especially with recoil.
-Just sayin.
Lay it between the U/L right in front of the FRONT take down pin. This gives you leverage to squish it and get the bugger back together.
Then trim the stuff that poops out between the two.
When I was an active duty Marine I did this to every issue M16A2 I ever shot during Intramurals, Division Matches, etc.
Worked great. Make a few and keep in your kit as they do get lost/wear out, etc.
Screws drilled and tapped work as well, however know that your U/L are made from AL. Even 7075 is going to peen over time. Especially with recoil.
-Just sayin.
you can put an o=ring around the front pivot pin lug
Pivot Pin O-ring size? - AR15.Com Archive
or IM me I will send you an accuwedge. took all mine out 10 years ago.
Pivot Pin O-ring size? - AR15.Com Archive
or IM me I will send you an accuwedge. took all mine out 10 years ago.
Last edited:
Thanks for the responses guys. I didn't want an accuwedge, but that was the only thing I heard off. The only reason why I cared is because I had heard that it would affect your accuracy. This is off a SBR engraved lower, so going out and buying a new lower is not an option. I don't plan on having a match rifle out of this, so I guess the accuracy lost will not be an issue for a "battle" rifle. Its only about 1 mm at the most, just enough to make it annoying, but I guess not really affecting operation at all and maybe only accuracy so little that I would not even notice it in the role that it plays.
It won't effect he accuracy at all- it's not like the sights and barrel are separate. Don't worry about it. My HP match rifle shoots very well with no dohickies or special bedding.
I qualified "Expert" many times shooting A1's (and A2s) out to 500 yards with iron sights on very loose rifles. I don't think it affects accuracy one iota. Maybe somebody out there can do a test.
I've always thought the same thing. The advertisements for accuracy improvement have been so enticing that I bought an accuwedge. I guess that's how they get you.
Put a strip of electrical tape under the upper receiver's takedown pin lug and another 2 strips on the top of the lower receiver's pivot pin ears. Thats the cheapest fix to wobbly fit I'm aware of.
Especially something soft that can "squash" and allow the upper to move upon recoil anyway. A minor amount of play shouldn't hurt anything.
My first AR (a Colt Match Target) had an Accu-Wedge in it when I bought it; no idea who put it in there, but the rifle was NIB.
Years after selling it off, I replaced it with a Stag Model 6 Super Varminter. No wedge, none added, still shoots 'lights out' at 250yd. I don't think there's need for 'improvement'; and I definitely don't like the idea of some soft plastic addition getting loose and gumming up the BCG at an inconvenient (What would actually be convenient, anyway?) time.
Greg
Years after selling it off, I replaced it with a Stag Model 6 Super Varminter. No wedge, none added, still shoots 'lights out' at 250yd. I don't think there's need for 'improvement'; and I definitely don't like the idea of some soft plastic addition getting loose and gumming up the BCG at an inconvenient (What would actually be convenient, anyway?) time.
Greg
