First build AR question

[callenlee]

Hi everyone, I'm building my first AR and have everything together on the lower receiver. It is an Aero Precision lower with PSA MOE parts kit and a UTG buffer and stock. Everything went together pretty smoothly. The only issue was the hole for the selector detent was too tight, but I got that worked out.

Because this is my first build and my first AR I did have a quick question. The hammer is putting tension on the bolt release so that the release will stay up if the button is pushed. I'm not too concerned about it because I realize the hammer will be back whenever the bolt release needs to be released. Am I right in not worrying about this or is it something I should look into remedying?

 

[Nick5182]

I noticed the same thing with my first AR build also. You don't have to worry about it at all. Once you get an upper completed and put on there, chances are you'll quickly forget that it even concerned you in the first place.

 

[ngnrd]

Not a problem. The hammer won't contact the bolt release once the upper is installed, it will be resting against the bolt.

 

[SilverCat]

It's how it is supposed to be, no worries.

 

[callenlee]

Great! Thanks for the replies. I read a lot of reviews about different receivers in my price range and it seems there were at least some experiences with each where people said things didn't line up correctly so I thought it best to get some feedback from those more experienced than I am with the platform.

Now my only problem is waiting another month or two before the fun money fund is sufficiently recovered to get a barreled upper. Thanks again.

 

[rjrivero]

As noted, this is normal. This is also the reason you don't want to "dry fire" the lower as the hammer will drop on the bolt hold open and cause damage.

 

[Blade First]

With the hammer back, if you check the bolt catch and it won't rock properly, you have an out-of-spec hole in the catch. The roll pin in the smaller hole will not act as a pivot and will prevent the catch operating properly.

Or perhaps the BC detent spring is kinked and preventing the detent from moving freely.

RE: dry-firing, a bigger danger than damaging the bolt catch is snapping off the top of the hammer because it is slamming into the back of the mag well.

Congrats on the lower build...Aero makes great products. I "chase" the detent holes for takedown and pivot pins and the selector with the proper-size drill to make sure there's no debris to stop proper action. Was that your problem?

 

[callenlee]

With the hammer back, if you check the bolt catch and it won't rock properly, you have an out-of-spec hole in the catch. The roll pin in the smaller hole will not act as a pivot and will prevent the catch operating properly.

Or perhaps the BC detent spring is kinked and preventing the detent from moving freely.

RE: dry-firing, a bigger danger than damaging the bolt catch is snapping off the top of the hammer because it is slamming into the back of the mag well.

Congrats on the lower build...Aero makes great products. I "chase" the detent holes for takedown and pivot pins and the selector with the proper-size drill to make sure there's no debris to stop proper action. Was that your problem?

Thanks for the feedback. I think the catch is good. It works properly with the hammer back and I've kept the hammer from falling freely when I checked the trigger and hammer for functionality. My takedown pins were pretty easy to instal. To fix the selector switch problem I used a punch to gently tap the detent down, pushed it out, and repeated a couple of times until it loosened up.

One trick I figured out was for installing the screw for the handguard. Mine came with a regular flat head screw and it was turning into something of a balancing act trying to keep the screw on the screwdriver long enough to get it in the hole. I ended up taking some painters tape and wrapping it around the tip of my screwdriver. This made the head of the screwdriver larger and gave it a bit of give. With that done, I could push the screw onto the screwdriver and it would stay until I got it started in the hole. I thought it was fairly nifty.

 

[HOOfan_1]

I used a screw starter to get my grip screw started

 

[Blade First]

The equivalent thread-pitch/length hex-head machine screw [Lowe's has a great selection] is so much easier to use with the add'l benefit that you are much less likely to cross-thread and damage the lower. The only caution is that you should not over-torque...if it doesn't easily thread in, suspect trash in the hole or a poorly-threaded lower.