Ruger AR 556

[Waynzee]

Hi fellas, has anybody shimmed the lower and upper on their AR 15 for a tighter fit and if so does it actually help with accuracy and hold up over a long time.

 

[rcoody]

Hi fellas, has anybody shimmed the lower and upper on their AR 15 for a tighter fit and if so does it actually help with accuracy and hold up over a long time.

a tight fitting upper is best but there are 3 ways that I know of to tighten up that fit.

put some small O rings on the front lug to tighten it up. lot of utube vids of it

then there is the acuwedge

and many lowers come with a tensioning screw installed. Puts pressure on the rear takedown pin

take your pick

 

[Waynzee]

a tight fitting upper is best but there are 3 ways that I know of to tighten up that fit.

put some small O rings on the front lug to tighten it up. lot of utube vids of it

then there is the acuwedge

and many lowers come with a tensioning screw installed. Puts pressure on the rear takedown pin

take your pick

Thanks for the info. I'm not sure about O rings or the acuwedge but I'll talk to my gunsmith about a tensioning screw on the rear takedown pin. That sounds like it would be solid.

 

[Kansaswoodguy]

Tight fit from upper and lower makes no difference on accuracy.
Best bang for the buck is a good barrel, a free float hand guard, an aftermarket trigger and load development

Barrel chambers in order of accuracy best to worst
223 Rem
223 Wylde
5.56 NATO

Things that may make a difference locktite barrel extension into upper receiver, using a heavy wall upper receiver i.e. DPMS slick side or Mega SBU,

Things in the voodoo category that help in our heads but not on the target clamp on gas block, tight fit upper to lower, bullet weight matched to twist rate.