Assembling my first lower

[rl45acp]

Ok guys,
I am going to be assembling my first lower this weekend. I have seen a few video's and read up on it through the net. It doesn't look like it is going to be that hard.

BUT..... I was just wondering if there is anything to look out for that isn't talked about very often. Maybe some tips and tricks that are hidden from view. I have all the tools that I think will be required, including masking and electrical tape, and those tools I don't have I will/can fabricate. I am an aspiring watchmaker so small pieces and parts and springs dont scare me in the least. The smallest part in the lower kit, is the the size of the largest part in a mechanical watch.

Specifics:
Spikes stripped lower
RRA lower parts kit

TIA
Rob

[MichiganMilitia]

Assembling lowers is a piece of cake a quite a lot of fun to do for the first time!

I highly recommend the how-to videos on the Brownell's website found here: http://www.brownells.com/.aspx/lid=11011/learn/

They cover everything and from start to finish it should take you no more than 45 mins. I've assembled three lowers using their vids as a guide and if I ever do another, I will use them again. Hope this helps and good luck!

[esaabye]

I used the follow site guide and it worked well.
http://www.ar15.com/content/guides/assembly/lower/

also someone told me to use old drill bits if I did not have the proper punch size and that did help.

[Quib]

I was just wondering if there is anything to look out for.....

Support the lower receiver on a block of wood when installing the trigger guard roll pin. If caution is not used here during assembly, and the receiver not adequately supported, it’s very possible to snap off a lower receiver trigger guard ear.

[rl45acp]

Great links guys, thanks. Nice to have the parts laid out in one photo. And thats is quite video series.

Heh, I know about using the block under the trigger gaurd. The first lower I bought has one of the tabs broken off by the DPO. It is a bit annoying, but I got it real cheap, and it functions just fine. I will probably use a .4" thick alumninum block to support it.

Well here I go. Wish me luck.........

[sniper7]

call me if you have any questions/problems. I think you probably still have my number.


I didn't read the other posts, but my quick additions:

tape off the lower to protect the finish when tapping in the pin for the bolt release

the trigger/hammer springs are tough and sometimes tricky taking a couple times popping them in there before they function just right.

make sure you do the function test of the trigger and make sure it catches with the trigger held back in the full pull position (no double taps/full auto)

support the ears when tapping in the pin for the trigger guard.

stay in a tight/small well lit room so when you launch one of the detent pins, you will have a better chance finding it. don't worry you will launch one... I have faith[Beer]

[MuzzleFlash]

My least favorite part is getting the front takedown pin in without launching the detent keeper and spring. I finally got a tool for that and it's made a big difference.

[gunhound]

Since most people don't have the pivot pin installation tool, go to a hardware store and buy a clevis pin. A clevis pin has the hole drilled in the end and makes it quite easy to install the front pin. I believe it is 1/4" dia.
I have built many lowers and it works great.

If you plan on using a .22 conversion, 22 dedicated upper or 9mm upper w/ ramped bolt, you will need to swap the RRA hammer to a smooth face hammer such as DPMS.
(The RRA has a nothced hammer)

[Tora]

Since most people don't have the pivot pin installation tool, go to a hardware store and buy a clevis pin. A clevis pin has the hole drilled in the end and makes it quite easy to install the front pin. I believe it is 1/4" dia.
I have built many lowers and it works great.


That's a great idea. I just tock an old screwdriver, cut the head off, and drilled the hole. Cost nothing but some time and effort.

[rl45acp]

Good news.I got her all together without a single hicup....or scratch.

Sniper7: I did use the tape trick, but I didn't need it as I did not tap the reciver with the hammer once. For future builds I wil continue to use the tape as insurance though. Also, I am quite used to hunting for small parts in my house, have you ever had a click spring fly out of the watch you were working on? heh. [Bang]

MuzzleFlash, Gunhound and Tora: I used the razorblade trick, but instead of the nasty sharp blade, I sacrificed one of my old feeler gauges. Worked ok, but I will be my shop making one of the pin tools in the next few days. Great idea.

Thanks all. I failed to mention, I built this for a buddy, so when he gets a chance to fire it, I can prouldy stand back and say quietly to myself, I did that.

[daemon734]

My least favorite part is getting the front takedown pin in without launching the detent keeper and spring. I finally got a tool for that and it's made a big difference.


no joke. A $5 tool from adco has made my life so much easier.

[Not_A_Llama]

Couple tips of my own:

Assemble your lower inside of a large plastic bag, so your detents/springs don't go flying.

You don't need a special tool for the front pivot pin and detent. Use the end of the pin to push in your detent, then rotate the pin into the receiver.