Home Forums Hunting & Shooting AR and Tactical Rifles LWRC M6 front post removal and options

I have an older LWRC M6 with the tall fixed front post. I really like the eotech green holographic sight, but that damn front post bothers me in the sight picture. I’m looking for some advice on swapping it out for a flip up. I’m not a very experienced gunsmith by any stretch, but willing to give it a try myself if possible.
1) should I be able to handle this myself and if so some suggestions are welcomed
2) once off, recommendations for what to put up there. Perhaps something that can be extended out a touch towards the muzzle. I don’t have a pic rail out too far towards the muzzle
3) other suggestions that I might not be thinking of

Nothing you replace it with will be as sturdy as the barrel pinned factory “A” frame front sight.

Yankee Hill makes a flip up front sight that might fit, but it won’t be pinned like you have it.

If I really wanted the front sight tower out of the way - I’d cut it off at the top of the horizontal gas tube bridge, and contour it to match - and not worry about a front sight.

I actually prefer the Front sight standing up there. The dot should rest right on top of the post but if you just focus on the target, you won’t even notice the front sight until you need it.

Your pics just now showed up for me. You have what is known as an absolute co-witness setup there. It still works.

You can also get a lower 1/3rd riser for the EOThingy and it will give you a bit more of a head up stance and clear the front sight better.

The "BCM Method" for removing the FSB :

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”). It’s 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. Do the banana dance.

Isn't the M6 a piston gun?

Yes it’s a piston gun.
Thanks for all the info. Now I’m having second thoughts about removing/replacing

If you do remove it, just chop it like AH64guy suggested. It’ll save you a lot of headache.

Sawzall fixes it quick & good.

That is more my speed

It should look like this when you are finished:



Just make sure you remove your optics first. The vibration will kill a scope.

That’s a nice clean look w/o all the messing around with the removal. I can see myself jacking the removal up. Maybe a clean weld on of a flip up front sight on the new horizontal could be possible.

I cut mine off with a dremel cutoff wheel and blued the cut. Looks just like the pic posted above. Wasn’t hard at all.

I know it takes a lot. But you can get used to that front sight in the view. I was going to chop ours and then realized its just learn to ignore and roll with it.

Its an option anyway depending on your brain. Its like folks saying they can't get used to a 2 stage trigger. That really means they never tried.

Regardless cutting em off with a hacksaw or Dremel etc... has been going on since we got into the game in the 80s. It works.

The taper pins come out easy enough too. Just solid placement of barrel, solid whacks. The RIGHT direction. IIRC you can look at tell which end is big and small if you look closely enough even.

Good luck.

BTW if you remove, whatever goes on next, is with set screws IMHO. If you are worried about them not holding use loctite 640 on the barrel and whatever. It always took heat and a 3 pound sledge and block of wood to remove those sight bases AFTER all set screws were removed... I"I'm fairly sure you could 640 them and never use a screw and would be fine.

Id leave it alone and get a mount for lower 3rd witness

Made by GG&G but I think they are discontinued because I can't find them anywhere anymore. I don't think there is anything wrong with the clamp on style over pinned.

Like Rost says, Use enough lok tite


I co-witness it with a C-More red dot

Leave it.
You may want to keep it, and go back to irons some day.
I am just using irons on my 10.5 incher. I kept it simple. It being a piston makes things different to deal with.