Stubborn Gas-block pins - Colt L6920 OEM2

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Tl;dr - Pins in gas block stuck. Looking for advice/tips from those how have dealt with this.

Ive been having some issues trying to remove some pins from a low-profile gas block on my 6920, and I was wondering if you could help!
I'm not a stranger to taking down an AR for cleaning purposes, but this is the first time I've tried removing a FSB/gas block. Unsure if this is just a common problem, with the 6920 in particular, or I'm just not doing it right..

I cannot even get the pins flush with the gas block itself, they seem to be really stuck. I've been at it for a few hours now trying to really whack the pins out with a hammer and some barrel wrench.

Gas block:
https://i.imgur.com/SJwOzPgr.jpg

Barrel wrench tool:
https://i.imgur.com/Tf4obAjr.jpg
(Its just putting dents into the thing at this point.)

Bottom view:
https://i.imgur.com/KxlUnBwr.jpg

What I've found out so far:
- Pins are generally taken out Left side facing up
- Tapping WILL cause pins to mushroom/expand
- Tried using some oil/lube, and wd40 as per another post. Nothing.

I've seen elsewhere that someone with this exact gas block had drilled the pins out, effectively DESTROYING it in the process. I'd rather not get to that point, thanks.
 
Reasoning behind the removal of this gas block, is that I've recently purchased a new floating hand guard, which requires the use of its own style of barrel nut.
 
Valid said:
Reasoning behind the removal of this gas block, is that I've recently purchased a new floating hand guard, which requires the use of its own style of barrel nut.
Click to expand...

What are you using to support/hold the FSB as your trying to punch the pins out? Do you have a FSB jig?

Also what kind of punches and hammer are you using? Are you trying to use a barrel wrench as a punch/drift?
 
Those pins are tight, I encountered the same issue. In the end, I took it to Reliable Gun and they were able to remove the pins without issue.

Valid said:
Reasoning behind the removal of this gas block, is that I've recently purchased a new floating hand guard, which requires the use of its own style of barrel nut.
Click to expand...
 
JohnnyP636 said:
What are you using to support/hold the FSB as your trying to punch the pins out? Do you have a FSB jig?

Also what kind of punches and hammer are you using? Are you trying to use a barrel wrench as a punch/drift?
Click to expand...

The entire firearm is on the floor, with a wood block holding up the barrel's end. Ive seen some of those FSB jigs in a few posts now, may need to get one tbh.

Ive been using a 1lb hammer, a mallet, and honestly just whatever else I currently have. Just after posting this forum I found another that mentioned I may need a 3lb+ hammer for these pins. Wasn't hoping to throw more money into the process of even i installing this hand guard, but its sure looking that way.
 
Sinasta said:
Make sure its being supported and your hitting it the right way. Some are tapered. I broke a punch doing it and eventually used a hardened nail and just pound away.
Click to expand...

+1 Yes that is what I was getting at, first you have to support what you are trying to punch the pins out of properly. So the energy and force you create with your hammer actually gets transferred to the pins and isn't lost because the block is not supported well enough.

Then you have to make sure whatever your using as a punch/drift is made of a harder material then the pins, if I understand correctly he is trying to use the side of a barrel wrench as a punch/drift. That isn't a good idea IMO you need a proper hardened steel punch. If OP's pins are denting his barrel wrench or whatever he is using as a punch, then that is a clear sign its not made of a hard enough material for the job..
 
Sinasta said:
Make sure its being supported and your hitting it the right way. Some are tapered. I broke a punch doing it and eventually used a hardened nail and just pound away.
Click to expand...

Yikes, yeah I'm 99% sure I've been hitting the right end of the pins. At this point, I may just need a heavier hammer..
 
Valid said:
The entire firearm is on the floor, with a wood block holding up the barrel's end. Ive seen some of those FSB jigs in a few posts now, may need to get one tbh.

Ive been using a 1lb hammer, a mallet, and honestly just whatever else I currently have. Just after posting this forum I found another that mentioned I may need a 3lb+ hammer for these pins. Wasn't hoping to throw more money into the process of even i installing this hand guard, but its sure looking that way.
Click to expand...

You dont need to spend money on a fancy jig, but a wood block is going to absorb the energy your trying to transfer into the pins. Its not hard enough of a material and will dampen your blows

Same with your tool, you need to get a proper hard steel punch, because it does not matter how big your hammer is or how hard you swing it, if your hitting a tool that is softer material then the pins. Pins are hard so you need something harder then them to knock them out. And the block needs to be supported well
 
JohnnyP636 said:
+1 Yes that is what I was getting at, first you have to support what you are trying to punch the pins out of properly. So the energy and force you create with your hammer actually gets transferred to the pins and isn't lost because the block is not supported well enough.

Then you have to make sure whatever your using as a punch/drift is made of a harder material then the pins, if I understand correctly he is trying to use the side of a barrel wrench as a punch/drift. That isn't a good idea IMO you need a proper hardened steel punch. If OP's pins are denting his barrel wrench or whatever he is using as a punch, then that is a clear sign its not made of a hard enough material for the job..
Click to expand...

I didn't know that the material had to be harder than the pins. Thanks for bringing this up.
Yes, I've been using some tools similar to punches, since my own are very fragile and don't wish to break them, theyre not meant for this. I've used some flat surfaces to see if I could even get the pins flush with the block, but it now makes sense why that would never work.
 
Valid said:
Yikes, yeah I'm 99% sure I've been hitting the right end of the pins. At this point, I may just need a heavier hammer..
Click to expand...

if you have a caliper or something you can measure fairly accurately, measure both ends of the pins. a tapper pin will be larger diameter on one end, so that is the easy way to find out which way they need to come out

Look at some videos on Youtube
this one the guy was bending punches that were too soft, then he got a proper tool and they came out
https://www.youtube.com/watch?v=-lxpxOMHLjM
 
I went through the same thing. Eventually I used a small cut off disk on my Dremel to cut the peened end of the rivet off. It still took a few strikes to come out. They come out by hitting the left side (control side) towards the right (ejection port) side
 
I used a Hockey Puck as a block, that and a few wood blocks to level the upper. As I was beating away I considered how nice it would have been to have a second set of hands to help hold it in place (I suppose there are merits to having a wife). As per another members suggestion I used two punches, a larger taper punch to get it started and a small pin punch to finish the job. I can't remember the sizes, and work is calling, hopefully someone else will chime in.
 
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