Removing pins from ar gas block

chexmix

New member
Anyone got any tips on how to get the pins out. I have been beating the hell out of them for about a half hour and they won't budge(I am hitting the right side). I am using the biggest hammer I have so that's not the problem.
 
What make is the rifle.. or the upper for that matter. Some companys don't follow the mil-spec standard.

Smith and Wesson does it the opposite way. Others I am unsure of off the top of my head.
 
What type of hammer and punch are you using?

Sometimes they need an extremely sharp rap to get started. The punch makes all the difference. The cheaper punches absorb the peak of the shockwave and will get you nowhere. I have had best luck with Starrett punches and so-so luck with Dasco. The advantage to Dasco is that they're about 1/10th the price and available at hardware stores. Starrett you'd have to get from a machine tool supplier, but you can find them on Amazon too.

For the hammer, 3 lb sledge is a minimum.

Get a good running start with the sledge -- it'll take confidence to bring that hammer down hard on a little punch you're holding with your bare hand!

The punch should be exactly, precisely coaxial with the pin. If it's crooked even a tiny bit, you'll lose a large portion of the striking force.j

The gas block should be supported firmly. I use the gas block bench block from Brownell's. It's not an ideal product but adequate, and works better than most workholding methods.
 
STOP............

Most AR pins are tapered pins and are driven OUT from the LEFT.

Buy or make a starter punch by cutting a standard punch off to about a 1/2 working length. You can also use a nail set.
The starter punch won't flex and bend and dissipate the force.

Next, get the barrel set up with wood blocks on a FIRM surface. A concrete floor works well.
If needed have a buddy help hold it steady.
If you strike the barrel and anything moves or bounces the force will be dissipated and the pins may distort and lock even tighter.

Inspect the ends of the pins. Since most AR pins are tapered, check to see which way the pins are driven in by comparing the ends of the pins to see which is bigger.

Once you get the pins moving with the starter punch, switch to a standard punch to remove them.
 
^^^^^^^^^^^^^^^^^

Perfect.

The only thing I can add is the face of the punch should be slightly concave to match the face of the pin. A flat face on the punch can mushroom the pin making it even more difficult to remove.
 
If you've been pounding on the pins for that long, quite possibly they're not coming out now w/o some serious effort. What are you using for a backing? A solid support and a good, straight impact with a suitable hammer "should" loosen the pins. Should and will are sometimes entirely different color horses. A machinist might be able to drill the pins out of the gas block leaving only a slight shell allowing removal.
 
If needed what "size" of pins to buy and
are they commecially available?

The FSB pins are a 0/2 taper, at least that's the size reamer you use to make the final hole size.

Pins can be bought from Brownells or Midway.
 
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