Slick sided uppers

[Dirtrax]

The method is to heat to fit. I thought I'd like to try it.
The part that is heated is were the barrel fits into the receiver. This has been working well for others. I thought I would ask to see if others could steer me towards a source that wasn't an expensive machined piece.

 

[ARlife4me]

The method is to heat to fit. I thought I'd like to try it.
The part that is heated is were the barrel fits into the receiver. This has been working well for others. I thought I would ask to see if others could steer me towards a source that wasn't an expensive machined piece.

i've never had any reason to do a "heat to fit" for accuracy or lap a receiver.

 

[rpol98]

thermal-fit, like BCM, just means you don't need to use shims to get the tight fit of barrel extension into the upper receiver front snout.

 

[UncleDano]

thermal-fit, like BCM, just means you don't need to use shims to get the tight fit of barrel extension into the upper receiver front snout.

If you think you need shims for around the barrel extension to make it fit the receiver, better think about getting a different receiver or barrel extension!

 

[ARlife4me]

If you think you need shims for around the barrel extension to make it fit the receiver, better think about getting a different receiver or barrel extension!

Shi.s are also used for timing of the barrel nut.

 

[pavementends]

We are talking 2 different issues. Shim around the diameter of the barrel extension to tighten the barrel to upper fit. Shims between the barrel nut and extension to time the barrel nut.

 

[Gregg C]

I much prefer the slick sided upper. Aero makes a nice one. I also have BCA side charger upper. The BCA upper to barrel fit and the fit to lower is quite loose. Shims are available to address both issues and the side charger is a nice feature. I built a very light 223 with out a gas system and use it as a straight pull bolt action. I do have to listen to well meaning folks explain how I need to adjust my gas block or buffer weights as the rifle is not ejecting properly. The 22 ARC sounds like a fun build.

Lol that's funny! I can just imagine!