I know this has no effect on accuracy in general but I would like to tame the wobble on my AR. I did purchase a accu wedge but there is still wobble from side to side. Enough wobble to make me want to throw the lower away. You can set it on the table and just jiggle it like a broken toy. What are options for tightening up the front end since the rear has a accu wedge already?

Accuwedge. Works great

You can buy special takedown pivot pins to take out the wobble. 
Or use RTV silicone to make it a tighter fit. 
People also use shims

It absolutely can affect system accuracy as the recoil path passes from the upper through the lower at various contact points to the body's and bag's support surfaces.  I personally have found a properly sized small o-ring wedged vertically into the gap between the rear face of the front receiver lug and front of the magwell, trapped upon closing under the feedramp area of the upper, tightens things up nicely, and a washer-like takedown pin shim from Brownell's to lessen the left to right rear lug slop is a nice addition, though takes a bit of practice to install after each opening of the receiver.

Did you buy the receivers together? As a complete rifle? What brand are they?  I ask because some have different size takedown/pivot pins, and if you have that much slip it almost sounds like you might not have pins that properly fit your receivers holes.

The Accuwedge is a decent solution.  If you want a more permanent solution (and have the right size pins) you can use a drill press to drill a hole under your grip in line with your rear takedown pin hole.  Then tap it so you can use a set screw to apply pressure to the rear takedown pin stud.  If your interested in this solution let me know, and I can give you more instructions and pictures.

Many of the higher end receivers use this method to mitigate slop and allow for an adjustable amount of tension on the rear stud.

Play between the upper and lower has never effected the mechanical accuracy.
It can can be annoying to an individual shooter and that can affect their scores if they let it.

My honest advice is to just forget about it and shoot/train with the rifle......this also goes for the "sproing" sound you hear in the buffer tube...just embrace the system as it is and carry on.

I just going to try the shims because it's winter and I got nothing better to do. The lower is a Anderson lower and upper is from PRI. I understand that the AR will have play in between the the upper and lower and this isn't my first AR. It's just this combo is just silly on how sloppy it is. Like I said before I already have a accu wedge in and there is still side to side movement. So in the mean time I will try some shims.

Thanks

Does it wobble with a full mag inserted?

My lower receiver came with a nylon-tipped tensioning screw that basically pushes up on the upper receiver.

Did you even read the OP, or just the title, Drop?




Foam ear plug, o ring, accuwedge, shims,....

Or just shoot it. It's an AR. It used to bother me,
no longer care. Full mag inserted will take up the slack.

Aero Precision Gen 2 lowers have this, if you need a make/model to search for OP.

You need more info to determine if the lower is even the problem though. Out of spec pins or upper could also be an issue. Do you have other ARs you could mix/match the 'problem ARs' upper/lower out of to track down which part is causing this?

No effect.  Shoot it and enjoy

I too had an Anderson lower, one with the "winter" trigger guard built in, and built a 7.62x39 upper with an AeroPrecision upper etc....had a small amount of "rattle" which I didn't care for, so I built up another lower using a spikes crusader [ I had 5 in a box, 2-rangetool/2-spikes crusader/1-anderson ], and its a lot tighter, there may be a small "bit" of movement but not enough to cause any "rattle" at all.

I am curious if the Anderson lower would be tight with an Anderson upper, however I didn't have any, I found some decent deals on the Aero uppers and really like them so I tend to just use them for all my builds [ except an A2 I used a Fulton Armory stripped upper for that ]........

Foam ear plugs work the best. Just trim it down until you can barely get the rear pin in and out and make sure the ear plug is squeezed flat. That way as it expands back to normal it makes it nice and snug.

Personally I'm not a fan of the tensioning adjustments or techniques that push the upper receiver up, away from the lower.

Best solution if you desire a tight fit, is to just get a lower receiver that is made for a tight fit.

Several manufacturers make lower receivers with the rear lug cut such that virtually any upper will need to be "bedded" in with a rubber mallet or the like. In factory build rifles this leads to a perfect snug fit that makes consumers happy. And frustrates some homebuilders if they don't understand the difference, which is why many manufacturers selling to homebuilders have gone away from the tight fit.

Unless something has changed, the following are all made for a tight fit:
RRA
generally the tightest and almost always require some work to get them joined to an upper

Stag Arms
AGP
almost always a snug fit but usually require less work. mixed and matched with different uppers you can sometimes find a perfect fit.

I'm sure there are others, these are just the brands I happen to know.

Alternatively, the old school service match way was to bed the rear lug into the lower using a bedding compound, which would be relatively easy to do with suitable caution.

This is why I like matched receiver sets.  

But yeah, accuwedge, shims, rtv, or just ignore.

I say just shoot and enjoy.  My $2,000 KAC has the worst wobble of any of my ARs but it shoots great.