AR-15 slop fix

The only real problem with that slop is it bugs the shooter.

Your little rubber bushings are by far the most cost effective way to take it out. If your pin holes are so worn that the slop is there, the oversided pins will significantly reduce it.

More often than not though, that's not where the slop is coming from, it will just be from an inexact fit between the upper and lower.

That's most common when you have Frankenguns, with U/L's made by different manufacturers.
Has anyone really done a test to see the difference?
 
I have used few methods to take out the slop of an AR15. Lots of debate about the effect of the slop on accuracy, I used my AR's for 200-300 yard Egg Shoot Competition and treat bedding quality no different then the bedding quality of my precision bolt rifles. I think it matters for high precision shooting. You have to first figure out where the slop is coming from…ie. loose pins or too much clearance in the rear receiver lug. Most all of the time for me it has been due to the rear receiver play/clearance. With AR15 Mil-spec rear lug fitment, the most effective solution for me has been to use the horseshoe shaped alloy Accu-Shims(below). They have kept a couple of my competition AR's absolutely free of play for more 10-15 years of heavy use.keep the pin well lubed! The common plastic AccuWedge types can work OK until the rubber fatigues. I used them before I went to the Accu Shim. To solve this, I drilled a hole(about 1/8"-3/16") in the center of the bottom disc portion and fitted a cut to length, stiff trigger spring, slightly larger then the drilled hole that is fitted in the hole to apply support tension. Getting the length of the spring right is important.
A couple of shooters I know have epoxy bedded the rear lug using the same method used to bed a bolt rifle tang area…and have had good success. Others have make their own Accu-Shim type shims from metal or plastic sheet stock. Lots for ways to skin this cat if you feel you need to.

 
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Has anyone really done a test to see the difference?
Not an official test but when ai first began using my AR's for Egg Shoots at 200/300 yards I observed occasional fliers that were difficult to explain. I noticed an improvement in group size and a reduction in fliers when I tightened up my receiver with no other changes in load, etc. And, my scores improved. I have seen similar improvement with my hunter AR's was well. I competed well against the bolt rifles, with the advantage of capturing a wind condition with the higher rate of fire.
A couple of targets from my Egg Shooters, 223(right) and 6mmAR(left)
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Good read by a military armorer when he supported the shooting tesm.

Ok... that is beyond a good read.
That is a great read!
Thanks for posting that!

Having just read the article.
I was doing several of the items he mentioned, for the last 6-8 years or so.
(this all relates to the AR-10/LR308's, I've built)
-Use a heavier upper (especially with a WSMs)
-Shim or Accu-Wedge the upper/lower union. The Aero set screw is great also!
-Loc-Tite 620 on the barrel extension, when that gets torqued
-Good triggers.

But the stuff on the bolt carriers, is definately new to me.
Any religious cleaning is new too

Thanks again for posting that!
 
Ok... that is beyond a good read.
That is a great read!
Thanks for posting that!

Having just read the article.
I was doing several of the items he mentioned, for the last 6-8 years or so.
(this all relates to the AR-10/LR308's, I've built)
-Use a heavier upper (especially with a WSMs)
-Shim or Accu-Wedge the upper/lower union. The Aero set screw is great also!
-Loc-Tite 620 on the barrel extension, when that gets torqued
-Good triggers.

But the stuff on the bolt carriers, is definately new to me.
Any religious cleaning is new too

Thanks again for posting that!

He was doing the carrier mod his way when I was doing mine, my way. Here is a picture of my version.

SS sleeve over the carrier. To accommodate the sleeve, had to bore the buffer tube. The weight is a substitute for the Tubb carrier weight. Just a brass turned down for press fit and press it in with a hydraulic press.

20200827_195040.jpg
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Get an Aero lower, they have a plastic tip set screw that bears against the take down boss. Or, have your lower drilled and tapped for a set screw.

Adjust set screw tension fir desired tightness between the receivers.
I have built 5 ARs. Two of them have the plastic tip set screw, Aero & Spartan. If I did another I would use the Aero receiver again. It's so nice in many ways.
 
Good read by a military armorer when he supported the shooting tesm.

I'm suprised lapping the barrel receiver extension wasn't included.
 
He was doing the carrier mod his way when I was doing mine, my way. Here is a picture of my version.

SS sleeve over the carrier. To accommodate the sleeve, had to bore the buffer tube. The weight is a substitute for the Tubb carrier weight. Just a brass turned down for press fit and press it in with a hydraulic press.

View attachment 333264View attachment 333265
How much weight is added to the carrier body with this?
 
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I'm suprised lapping the barrel receiver extension wasn't included.
I waited months for Brownell's recommended lapping compound to go with their lapping kit. The quality Aero Precision receiver and Faxon .223 wylde pencil barrel I used fit so well there was nothing to lap.
 
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