AR upper and lower tight fit.

[muntz]

I have an RRA upper I would like to mate with a Stag lower. The take down pins are not tight individually but if I insert either the rear or front pin and then attempt to put in the opposing pin I actually have to tap it in with a mallet to get it to seat all the way. And to remove the take down pin I have to tap it back out.

Other receivers match up just fine. I have a CMMG upper and a dedicated carbon 22LR upper and both have no problems.

The pins individually fit fine. Any tips?

[stphnman20]

I have a CMMG upper and a lower Stag.. Mine is also really tight.. It's easy to put in but hard to get out..

[40caldeserteagle]

If you do a quick search here and at AR15.com, it seems that there has been some fitting issues with Stag lowers. Looks like a batch [?] was made out of spec. I don't have any real insight into the problem though. I think the guy that posted here was named Moulton but I could be wrong.

David F.

[Stockton]

My stag lower with the Vltor Vis is a tight fit. At first I had to do the same with a delrin punch and brass hammer to tap it in/out. After several cleanings it has become easier with wear. Upside is that i have a very good fit with my upper and lower without any wobbles. Just keep it lubed and continue with your methods. It will work its way easier over time. I would say its better to have such a tight fit rather than a poor fit.

[muntz]

Good to know. I knew that a good tight fit is desirable just wasn't sure about needing a mallet to get the take down pins in and out.

[Hoop]

Combination of lower and upper being slightly out of spec. One half a millimeter can be the difference between pulling the pin out with your hand vs. using a screwdriver. I have 3 stags and 2 are a little tight (one was WAY too tight, I had to use a file to get a proper fit). Like people said previously they must have had a run where some were out of spec. The upside is that none of my stag rifles rattle whereas my CMMG made all sorts of noises.

[Jicko]

Just polish, sand or file down your pin a little....

It is much better to work on a $2 pin than the upper or the lower itself.

[moulton]

Combination of lower and upper being slightly out of spec. One half a millimeter can be the difference between pulling the pin out with your hand vs. using a screwdriver. I have 3 stags and 2 are a little tight (one was WAY too tight, I had to use a file to get a proper fit). Like people said previously they must have had a run where some were out of spec. The upside is that none of my stag rifles rattle whereas my CMMG made all sorts of noises.

If its anything like mine, contact Stag

[bwiese]

RRA uppers are in their own world and this is source of frequent complaint - they may have 'tweaked' the spec for their own complete rifles/uses.

Your Stag is more likely in spec than the RRA upper. But work on the $2.50 pin and not the receivers .

[stphnman20]

Your Stag is more likely in spec than the RRA upper. But work on the $2.50 pin and not the receivers .

And how do I go about doing that?

[Ballistic043]

while some stag lowers as of recently have been made out of spec, stag has always had a tight fit in my experience. actually most of them have been perfect, tight enough not to wobble but easy enough to field strip when needed. i always laugh when i hear these problems with stag because ive built 4-5 of them with no complaints..

[PIRATE14]

while some stag lowers as of recently have been made out of spec, stag has always had a tight fit in my experience. actually most of them have been perfect, tight enough not to wobble but easy enough to field strip when needed. i always laugh when i hear these problems with stag because ive built 4-5 of them with no complaints..

Upper lower.....fit always a bone of contention....99 percent of them time they go right together...

Every now an than some uppers like one lwr not the other but it's only a hair off.....just polish or remove a small amount of material off the pin.....

Now Rock River are the tightest ones in the bunch......so we know who makes most of those so, my .02 is that spills over into other production runs......

Most guys complain about the loose fit which really isn't.......

[stphnman20]

Well I have a CMMG upper and Stag lower.. It's really really tight.. The holes dont match up.. Just like Moultons pic..

[hawk81]

Hell, my stag lower is a loose fitting lower. I have a del-ton upper on it and it wiggles quite a bit.

[savs2k]

i had a stag lower and a dpms upper. really tight fit. I would have to tap in and out the take down pins. But it was a new lower and lpk.