AR-15 Slop between Upper and Lower

[Minuteman75]

Just finished installing my Lower parts kit into my stripped lower (cmmg) and mounted the upper (dpms). There seems to be quite a bit of slop between them. Is there a way to tighen this up? In my other lower I noticed a piece of rubber shimmed under the rear take down pin could this be my solution? any Ideas?

[sava6e]

yes its called a accu-wedge

[tommyid1]

hey man that slops mil-spec lol j/k what he said ^^^^^

[NSR500]

JP tensioning pin is better than the accuwedge because it will not cause additional wear to your gun. The JP pin pulls the upper and the lower together whereas the accuwedge pushes the upper away.

[Shane916]

Slop is acceptable.

[Minuteman75]

Thanks for the quick replies. That sounds like it will do the trick.

Oh and just for the record i like mine TIGHT.

[redcliff]

Sometimes a different pivot pin can help; the spec is .250 and smaller ones can cause rocking between the upper and lower.

[bomb_on_bus]

JP tensioning pin if you have the 32.00 apiece to spare or 4.00 for the accuwedge.

[foxtrotuniformlima]

I'd suggest the Accu-wedge first as it makes the takedown tool-less. The JP tension pin will do a better job IMHO but requires a tool.

[ar15barrels]

Over time, the accuwedge causes more wear on the holes.
The best solution is to just realize that your sights are on the upper with the barrel so the slop does not matter one bit.
The slop is a sign of it being closer to mil-spec.