AR Hammer pin help

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Can someone give me advice on an AR hammer pin install? Is there some trick to it? I am doing my first ar lower assembly, and having difficulty aligning it to the hole. Thanks.
 
Can someone give me advice on an AR hammer pin install? Is there some trick to it? I am doing my first ar lower assembly, and having difficulty aligning it to the hole. Thanks.

Are you using a drill bit or punch to help you get the holes aligned?

After the holes are aligned in place with a drill bit or punch, you just press the pins, or tap them through lightly with a gunsmithing hammer.
 
Thanks for the advice. Now I have a new problem, I just sent the pivot pin detent across the cellar!! I found the spring!
 
Thanks for the advice. Now I have a new problem, I just sent the pivot pin detent across the cellar!! I found the spring!

BTDT. This is why (I learned) you need a tool box with spares.

Can you filtch a detent temporarily from a spare LPK?

Are you anywhere near Windham Weaponry?

Any good shops nearby that stock small parts?

Brownells is pretty reasonable for shipping, but it'll set you back until next Thursday.

Aero offers a LPK (think spare parts) for $20 with no fire control parts or pistol grip:

https://www.brownells.com/rifle-par...triggerguard-prod130134.aspx?avs|Make_3=AR-15

Brownells doesn't have them in stock just now, but google the manufacturers part number and somebody does.
 
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I have one extra lower parts set here, so I can use the detent from that. Thanks for the advice, I will be ordering spare parts.
 
Thanks for the advice. Now I have a new problem, I just sent the pivot pin detent across the cellar!! I found the spring!

You're not an AR assembler until you send pins and springs somewhere into oblivion. Almost worth doing that stuff in a small, clean room so that when stuff goes flying you can find it. If you use a bathroom, don't forget to close the toilet lid and sink drains.
 
You're not an AR assembler until you send pins and springs somewhere into oblivion. Almost worth doing that stuff in a small, clean room so that when stuff goes flying you can find it. If you use a bathroom, don't forget to close the toilet lid and sink drains.
I had a few parts go fling over the years...when renovating the basement my daughter found a detent and spring in the corner while cleaning up a bit.
 
I had a few parts go fling over the years...when renovating the basement my daughter found a detent and spring in the corner while cleaning up a bit.

I fully expect to find something like this when I clear out the basement to move...

pile-of-metal-coils.jpg
 
Best advice I got while assembling things that are spring loaded was to assemble it inside of a clear plastic bag. Makes them not shoot into oblivion.
 
Best advice I got while assembling things that are spring loaded was to assemble it inside of a clear plastic bag. Makes them not shoot into oblivion.
I was using a large clear tote with holes cut in it for my arms.
Especially useful for the Unknown disasemblies. Its also doubled as a mini sand blaster.
 
I use a dummy pin, usually a take down pivot tool which is just the right size. Start the pin in one end and drive the dummy pin out the other side, it usually keeps the whole works from cocking out of alignment while your putting the pin in.
 
The hammer pin is the easiest to install. The "just slide that shit in" comments are correct. put the hammer in, apply force in the right place to align and slide the damn pin in.

I assume you have this all sitting in a vise with a vise block. When the lower is securely in place, this is all pretty easy. If you dont, that will explain why you dont have enough hands to get it done.

The pin that goes through the trigger/sear is harder (still easy) and you just use a 3/32 punch to align the holes and then put it out with the pin.

The front detent for the takedown you use a box cutter to hold the spring/detent in place while you side the pin in.

Anderson OOPS! Kit or equivalent is an easy way to get a bunch of spare parts. If you do lots of builds, you can buy all the parts in bulk, but if you just need a small collection of parts...
https://www.opticsplanet.com/anderson-manufacturing-oops-spare-kit.html
or at 100 other places
 
This the gayest thread ever. Just slide that shit in and get it over with.

A casual perusal of the topics list gives me a firm hunch that the OP is installing a fire control group in an 80% receiver that the milled himself--and that his trigger-pin holes might be ever-so-slightly misaligned and not have as generous tolerances as you are no doubt used to. In that circumstance, aligning things absolutely perfectly with punches or drill bits--especially when installing the trigger pin--might prove useful.
 
Is there any advantage of NM trigger pins over standard trigger pins?
Other than just being very well fitted and smooth. Not really.
The pins that came with my NM trigger are night and day on fit and finish compared to mil spec
 
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