Stuck parts - advice?

[Mo_Zam_Beek]

It ain't supposed to be this hard....


Trying to swap the OEM HGs on a 6920 with a DD Lite.

Gas tube roll is @ 1/2 way out and will not go any further. I have broken 2 1/16" punches, bent 4 or 5 nails, as well as a small Allen wrench that I cut down. I have tried grabbing it with a pair of vise grips - no joy. I have tried to move the tube back by hand, I have tried to gently grab the tube with the vise grips and pull it back - nope.

The pins at the base if the sight tower are peened over to the point were beating on them with a punch does nothing.

Anyone have thoughts before I break out the drill?

If I do break out the drill, where do I get replacement GT roll pin and FS tower base pins? Colt doesn't use goofy proprietary size for these do they?


TIA

[AMMOTECH]

Replacement parts...
Brownells should have most small parts. You have to search around to find what you need.
They used to have an AR parts & tools catalog.

http://www.brownells.com/.aspx/cid=1...ts/Rifle_Parts

Do you have a block to support the front sight while your trying to drive the pins out?

.

[polymorpheous]

http://www.thecitizensarmory.com/node/62

Cheap shipping too.

The gas tube roll pin is the easiest pin to remove in my experience.
Something is very wrong or you are doing something very wrong.
Hope you get this resolved.

I would also recommend against drilling out the taper pins in the FSB.

[Hmac]

The gas tube roll pin is 5/64 inch, so that size roll pin punch is what you need. If you've been using something larger or smaller than than, you may have bugger up the hole in the gas tube to the point where where drilling it is all you have left. Use a 5/64 drill bit...

I got tired of bending my long punch and bought a purpose-built gas tube roll pin punch. Haven't had a problem since. Adco sells them for about $5 IIRC.

[MistWolf]

It ain't supposed to be this hard....


Trying to swap the OEM HGs on a 6920 with a DD Lite.

Gas tube roll is @ 1/2 way out and will not go any further. I have broken 2 1/16" punches, bent 4 or 5 nails, as well as a small Allen wrench that I cut down. I have tried grabbing it with a pair of vise grips - no joy. I have tried to move the tube back by hand, I have tried to gently grab the tube with the vise grips and pull it back - nope.

The pins at the base if the sight tower are peened over to the point were beating on them with a punch does nothing.

Anyone have thoughts before I break out the drill?

If I do break out the drill, where do I get replacement GT roll pin and FS tower base pins? Colt doesn't use goofy proprietary size for these do they?


TIA

The pins holding the FSB to the barrel are often tapered and can be driven out in only one direction. Normally, they are driven out from left to right. Here is a picture of the Brownell's Sight Block from their website: http://www.brownells.com/.aspx/pid=2...HT_BENCH_BLOCK

It's marked to show which side of the FSB you need to be on to drive the pins in or out. If the pins were drilled & installed correctly, use this as a guide.

The end of the gas tube pin may have become peened a bit, causing it to stick. Try tapping it back into place. Unless I'm mistaken, the gas tube pin is straight, not tapered and you should be able to remove it from either side

[MarkG]

The gas tube roll pin is 5/64 inch, so that size roll pin punch is what you need. If you've been using something larger or smaller than than, you may have bugger up the hole in the gas tube to the point where where drilling it is all you have left. Use a 5/64 drill bit...

I got tired of bending my long punch and bought a purpose-built gas tube roll pin punch. Haven't had a problem since. Adco sells them for about $5 IIRC.

5/64 is correct...

1/16 is to small. You have probably flared the roll pin inside the FSB because a 1/16 will fit inside a 5/64.