Seriously BCM? What do you use for FSB pins? Or: Never invade Russia in Winter.

[Leonidas24]

I mushroomed out the head of a taper pin on a S&W sport that wouldn't budge and ended up 1) grinding the end of the taper pin flat 2) dimpling it with a center punch and 3) putting it in the freezer for an hour to get the metal to contract. After that I was able to get a punch with a 3/16" shaft that tapers to 1/16" with a flat end into the dimple and a firm whack drove it out on the first hit. I spent the better half of an afternoon trying to brute force that pin out before giving up and trying less taxing methods, which ultimately won the day.

[Iraqgunz]

Good luck getting another FSB installed. I think Randall at AR15Barrels.com (?) is one of the few that can do it correctly.

Sorry I haven't gotten back to this today. Been a long one. Showed 9 houses and fired a contractor! Oh and I made it by the Gun shop, where I am happy to say I found vindication!

Did we get the pin out? Nope. Not even close. Concrete floor and 3 of us got the pin to move about 1/16 of an inch. I want to know when BCM hired Hafþór Björnsson to install these things. Don't get me wrong, it makes me want to see the factory even more. But tell him to take it easy ok Paul?

All Joking aside we did work on this for a good 30 minutes. Once we applied heat we got it to move a tiny bit as I mentioned above. However that was all the movement there was. Finally we gave up. Since the FSB was already messed up we decided just to cut it off.

Here is the section with the in. You can see how much we were able to get it to move.

Attachment 43546

So I am in the market for a .625 FSB or Gas block if anyone has one.

Oh the up side I did walk out of the shop with a Saint. Now THOSE pins I was able to get out and install that rail. The really sad part? I don't think I like it.... Yeah. Where did I put my Woodford?

[TommyG]

I mushroomed out the head of a taper pin on a S&W sport that wouldn't budge and ended up 1) grinding the end of the taper pin flat 2) dimpling it with a center punch and 3) putting it in the freezer for an hour to get the metal to contract. After that I was able to get a punch with a 3/16" shaft that tapers to 1/16" with a flat end into the dimple and a firm whack drove it out on the first hit. I spent the better half of an afternoon trying to brute force that pin out before giving up and trying less taxing methods, which ultimately won the day.

LOL, I recently did the same to a Starrett punch on a BCM FSB pin too. Before IG chimes in, that one was on me. I had it on the bench top and should have gone to the floor or put the steel plate I use for pounding things on the bench top. Don't work on your stick when you are in a hurry, it never ends well for either of you.

[kwelz]

Good luck getting another FSB installed. I think Randall at AR15Barrels.com (?) is one of the few that can do it correctly.

As usual you are on point. Low Profile Gas block and longer rail it is!

[bb223]

Does anyone think a big block of lead would be good to back an FSB on a bench while you remove the taper pins?

No plans to do it anytime soon (one BCM was enough ) but it's something I've been wondering about.

Certainly cheaper than brass too.

[williejc]

About stubborn pins. Would an arbor press with pin attached work to remove a stubborn pin? Harbor Freight has them at $24.97?

[Ryno12]

Does anyone think a big block of lead would be good to back an FSB on a bench while you remove the taper pins?

You're only as good as your weakest link, that being the workbench. That is why many, including myself, recommend a concrete floor. Many benches will "bounce" with each hit. You need a stout foundation.
I'd think you'd also transfer a lot of lead to your firearm at all the points of contact too. Not a deal breaker but just an extra step for removal.

I actually prefer the orange Brownell's block. It fits well & offers ample support during pin removal. The reason for all the distaste for it here totally escapes me. They work very well IMO.

[dentron]

Sorry I haven't gotten back to this today. Been a long one. Showed 9 houses and fired a contractor! Oh and I made it by the Gun shop, where I am happy to say I found vindication!

Did we get the pin out? Nope. Not even close. Concrete floor and 3 of us got the pin to move about 1/16 of an inch. I want to know when BCM hired Hafþór Björnsson to install these things. Don't get me wrong, it makes me want to see the factory even more. But tell him to take it easy ok Paul?

All Joking aside we did work on this for a good 30 minutes. Once we applied heat we got it to move a tiny bit as I mentioned above. However that was all the movement there was. Finally we gave up. Since the FSB was already messed up we decided just to cut it off.

Here is the section with the in. You can see how much we were able to get it to move.

Attachment 43546

So I am in the market for a .625 FSB or Gas block if anyone has one.

Oh the up side I did walk out of the shop with a Saint. Now THOSE pins I was able to get out and install that rail. The really sad part? I don't think I like it.... Yeah. Where did I put my Woodford?

Did you cut the barrel?

[556Cliff]

The orange Brownells FSB bench block is complete junk and offers no support for pounding the pins on the FSB. It will also (at least mine did) bend up the handguard end cap because the block is not cut right to except it, I believe Randall of AR15Barrels.com has said the same of the one he had. I sent mine back to brownells for a refund.

I have this now and it actually does support the FSB and barrel correctly for pounding the pins on the FSB. > https://rguns.net/shop/r-guns-barrelreceiver-block-set/

[556BlackRifle]

I bought one of these on sale for $19.99 several years ago. I don't usually recommend this brand but I've removed and installed several FSB with it and it has worked perfectly well for that task.

Another important item is a proper punch like this one. Once loose, you can finish it with a proper sized drift punch.

Lastly you need a good hammer and solid work surface.

In some cases you may need to apply heat then a few drops of penetrating oil. Let it sit for a few hours and see if you can knock it loose.