Quick post: anyone know what size punch needed for gas block?

[wareagle]

Quick post: anyone know what size punch needed for AR15 gas block? I am needing to convert upper from carry handle to flat top upper. I plan to swap, but not sure of roll pin size.

Edited April 21, 2012 by wareagle

[TnShooter83]

5/64" for the gas tube.

and it's not common in a standard punch kit.

So the next best thing is a 1/16" drill bit. And be careful as drill bits can and will break. And when they do they are sharp and hurt like crazy when you stick one in your hand.

I'd personally cut the drill flutes "spirals" off the bit and proceed carefully......

The 2 larger pins on the bottom of the FSB are normally tapered and can only be driven out one way. look at yours and see what way you need to drive it out.

I pretty sure they are 1/8"...but can not remember.

You will be driving the pin from the smaller side. So the big side comes out first. On most the left side is smaller...but not all are that way, so be sure to look.

Some are straight pins and can be removed from either direction. Just look at yours to see.

Go here for details on removal of the gas block / FSB.... About 1/3 the way down the page.

http://www.ar15.com/..._4/226782_.html

good luck man.

Edited April 21, 2012 by TnShooter83

[Garufa]

If you're going to remove the front sight block do yourself a favor and put some good penetrating oil on the pins, like Kroil, the day before. It will make like much easier.

[wareagle]

Thanks for tips. Drill bit idea is very good.

[wareagle]

All done. The drill bit worked perfectly. The as tube was awful. I ended up removing front sight rather than trying to move from block.

[mikegideon]

The worst thing about the gas tube pin is getting it started when you put it back in. Roll pin punches are your friend.