Need tips for assembling a lower

AR/M4 AR Technical Discussion
1

I just assembled my second lower. Both lowers ended up with bare aluminum showing around the trigger pin and trigger guard holes. I know this is just cosmetic but if I can change my technique and avoid the resulting amateur look I would. The trigger pin blems are minor but the blems around the trigger guard hole are annoying. I used Mega lowers and Mapul trigger guards. I used the correct roll pin punch both times. I tried the vice-grip method on my second lower after I already put a few blems on the lower so I don’t know if that method would work any better. The trigger guard pin fit is very tight. It takes a good wake of a hammer to get it started.

Any advice, other than it a tool don’t worry about it, would be appreciated.

2

Good question,I messed mine up in the same area just a tad,in fact I still can’t get the same pin in all the way,still working on it.It is a Doublestar lower with a DPMS parts kit,I know,I know,should of used a different parts kit, I ordered a stag lower kit last night for my next build. Tag for replies to the original posters question.Thanks.

3

Wrapping the vice-grip jaws with some thick electrical tape worked really well for me.

4

I used about 4 layers of masking tape all round the hole of which ever area I was inserting a pin. That helped a LOT.

5

you say roll-pin punch, did you start with a roll pin guide? Those help to get the pin started and, for me, minimize “off-strikes”.

6

No roll pin guide.
I can see how that would help.
I’ll get some for my next build.
Maybe try a layer on tape on the receiver as well.