A3 Flattop Upper Receiver Assembly Left-Handed

Current stock: 0


The A3 upper receiver assembly is made to mil-spec standards and includes a picatinny rail on the top, dust cover, and installed forward assist.


Pivot/Takedown Pin Size: Small pin - .250"

Material: Forged and mil-spec with type 3 hard coat anodizing and a picatinny rail on top

SKU: STAG300412L


Q: Are the bolt carrier and charging handle included?

A: The bolt carrier and charging handle are sold separately.


Reviews (3)

Archer Bell 7th Jun 2019

22 Nosler update

My 1st review can be read where I used a Stag Arms left hand upper to build a 22 Nosler rifle. Everything went together with no problem. Once I got to the range I was initially disappointed with the cartridge. It was tearing up case heads, leaving ejection and extraction damage. I added an adjustable gas block and after it was turned there was a marked improvement. At first I was also disappointed in the accuracy from factory ammo. I have been able to develop a handload using the Nosler 70 grain bullet that stayed right around the 1” average. This gives me an alternative to the 223 Rem. I am really enjoying the rifle now and I am glad that Stag offers this upper. I am waiting for them to be back in stock because I want to build a 300 blackout.

Archer Bell 24th Sep 2017

Great for a build

I waited to try a new caliber rifle. I was impressed by what I was hearing about the 22 Nosler and wanted to try it out. I decided to build my own since I doubt that Stag is going to offer this caliber anytime soon. All of the other components fit nicely with this upper and look great. If the rifle shoots as good as it looks I will be pleased.