Assembling a lower with a stock pre-pinned

[Amicus]

Due to Massachusetts “AW” ban requirements, I have to deal with a lot of headaches when I demonstrate ARs to noobs (I do this all the time for a club). Despite my affection for A1 stocks, a lot of guys want to play with collapsibles, even if they are pinned to comply with the law.

For various reasons, I am thinking of having several different stocks pinned to carbine receiver extensions prior to installing them. I have never installed a receiver extension with a pinned stock (not at the fully closed position), but can think of no reason why it can not be done.

Am I missing anything? Is there something wrong with this idea (other than the fact that the law is misguided)? Will I suddenly hit a problem in assembly that I will regret?

Just asking for help, ‘cause I’ve messed up before.

[warpigM-4]

I could not see any problems with doing that .I have Pulled one of my receiver extension off and put it back on with a stock attached before it was a little easier getting it straight on the weapon having the stock line up right

[JimT]

I see no issues with installing a pre-pinned stock/RE assembly. If one were to use a tool such as the Hammerhead Tool, one might be in for a surprise. Great tool, but avoid it for your install.

[Amicus]

Thanks guys. I really like the Hammerhead, but I have several specialized alternatives.

[Hdog83]

No issues - I've done this many times. I actually ordered a bunch of VLTORs that were "pre-pinned" a few years ago. I've installed / swapped several of them on and off of various ban-compliant rifles, never with any issue. Just make sure you are happy with the length of pull at that particular setting before you have it pinned / pin it yourself.