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I'm trying to install my DD rails for which I need to install the DD nut. I'm trying to punch out the gas block pins to remove it so I can install the barrel nut, but they won't budge. I have the correct set of punches and I'm using the Brownells sight tower/gas block bench block. I've shot some penetrating oil onto them and let them sit overnight but they still won't budge. It's a Colt 6920 and the pins are not tapered. Any suggestions?
This is how BCM handles them:
From speaking with customers, it seems BCM FSB taper pins are harder to remove than some others. When we do it here, we can knock the pins free in under 60 seconds.
Here are some basic pointers on the way we remove them.
1) It takes Two. You will need a buddy to hold the upper group stable as you pound out the pins. You will not be able to get a good concentrated force on the pins if the upper is wobbling around (even a little bit).
2) Action Jackson. You will need a couple of action blocks (see Brownells for a good selection). These will be great platforms to stabilize the barrel. Also get the Brownells FSB block. You may have to mod the shape of the FSB block if using a free float.
3) Installed from starboard side. Milspec FSB are drill and the reamed for taper pins. The reamer runs from the right to the left (pointing the muzzle at the bad guy). So BCM pins need to be removed from left to right. Cannot be done the opposite way.
4) Secure that carbine. Using action blocks and the buddy system secure the upper group so the left side is facing up.
5) Get a fat one. We do not use those small radius head punches to break the pins free. We use a much fatter punch (5/16). Its a meaty sucker. Lots to hang on to, and enables you to put some force on the hammer. Using a 5/16 punch and a 12oz hammer, give her a smack. Anywhere between 1 and 6 smacks, and the pin moves. All you want to do is to get it to move to about flush.
6) Grab a skinny one. Now get the tiny little 1/8 punch to push the pins out of the FSB. They are already broken free, this just drives the fully out. Tap, tap, tap.
7) Celebrate. You are done.
... It's a Colt 6920 and the pins are not tapered...
:confused: They should be...
Colt pins can be hard if the rifle has been fired much. The instructions above will serve you well. Keep in mind that to start them moving out you will have to smack them, probably harder than you would think. Just make sure that your punch is hitting square on the pin and not at all on the FSB.
:confused: They should be...
Yea, I will double check but both ends look to be exactly the same diameter.
Some tips I've given out over the years, after dealing with my own stubborn FSB pins....
Work on a solid surface. A flimsy or bouncing tabletop or workbench will only absorb the energy from your hammer rather than transferring it through to the FSB pin.
Try using the appropriate sized nail set to get the pins broken loose. The nail set head is concaved, which I've found fits the FSB taper pin heads perfectly.
This concave design keeps the nail set firmly in place while hitting it with the hammer, preventing slippage off the pin head which can happen with a flat faced pin punch.
Use of a nail set also prevents the mushrooming of the pin head which can happen with stubborn pins.
Once the pins have broken loose, follow up with removal using a std pin punch.
Yea, I will double check but both ends look to be exactly the same diameter.
The difference in the taper is vary small, .01" variance if I remember correctly from large side to small side. I doubt you can tell while the pins are in and it takes a micrometer to measure once they are out.
they are definitely taper pinned, and you're probably driving them tighter. they drive out from non-ejection port side to ejection port side.
i use a press to press them out, rather than destroy them trying to punch them out. since you have an FSB block, this sshould be really easy for you
Got em out. I decided to not be such a Nancy with my hammer and they came out. They are in fact tapered. They sure look the same size on both ends when they are installed, but sure as shit when I pulled out the callipers i discovered the difference.
Now however I have a different dilema and I'm f'n pissed. I was installing the DD lite barrel nut with DD lite wrench and as soon as I got around 60 foot pounds of torque the teeth on the wrench stripped. I then tried to then back off the nut so it was at least indexed correctly and the notches in the nut also stripped. The DD directions say to torque between 55 and 70 foot pounds and I was well within that range. I can't believe how soft the aluminum is on these pieces. Did I get some bad parts? So now I'm stuck with an nut that isn't indexed and one that I currently can't get off. I've sent an e-mail to Daniel Defense and have since calmed down a bit but I was fuming for a while. We'll see how they respond.
index? the lite barrel nuts need no indexing...
I was under the impression that the allen screws that tighten the rail to the nut and keep it from spinning need to enter the "channels" of the nut. The directions don't specifically say this, but the "channels"in the nut (the same channels the wrench fits into), seem to be spaced just for this purpose, and intuitively this would seem logical. I can't believe that you just tighten these screws against the nut without them locking into something, or am I wrong?
I was under the impression that the allen screws that tighten the rail to the nut and keep it from spinning need to enter the "channels" of the nut. The directions don't specifically say this, but the "channels"in the nut (the same channels the wrench fits into), seem to be spaced just for this purpose, and intuitively this would seem logical. I can't believe that you just tighten these screws against the nut without them locking into something, or am I wrong?
yep.. you're wrong. the screw heads themselves provide the anti-rotation limiting. but i've yet to see a properly installed lite hit the screw head... the boltup plate squeezes the shit out of that nut.
yep.. you're wrong. the screw heads themselves provide the anti-rotation limiting. but i've yet to see a properly installed lite hit the screw head... the boltup plate squeezes the shit out of that nut.
My rail is the Omega FSP which uses the Lite barrel nut by not the boltup plate. Same deal?
i thought we were talking about the lite... my bad. i haven't installed an omega X, but i doubt there's any indexing with the nut. i bet you a dollar, in fact. my understanding is that it clamps down on the lite nut just like the regular omegas clamp down on the OE nut.
didn't it come with instructions?
i thought we were talking about the lite... my bad. i haven't installed an omega X, but i doubt there's any indexing with the nut. i bet you a dollar, in fact. my understanding is that it clamps down on the lite nut just like the regular omegas clamp down on the OE nut.
didn't it come with instructions?
Yea, but the isntructions are pretty vague. Basically the just says to install the barrel nut, torque to spec, then put the rail on and tightnen the little allen screws until resistance is felt. Just seems hard for me to believe that the friction from the screws is all there is to prevent rotation. Oh well, maybe some things are as easy as they seem. If that's the case I'll just intall the rest of the rail and worry about the stripped nut when and if I ever feel the need to change out the rail.
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