problem removing a handguard

[yrs]

I recently bought a complete upper for my AR pistol. Now I want to change the muzzle device. It's a 7.5" barrel in a 9" slim profile keymod handguard, so the handguard must be removed to properly install and time the muzzle device. It seems simple enough, remove the screws at the bottom end and the handguard should just slide off since it isn't the screwed on type. Well, the handguard won't budge an inch. I tried real hard to pull the handguard and it doesn't move at all. Any idea why and what I can do? Thanks for any tips or advice.

[Pofoo]

If you're completely sure that there is nothing (bolts, pins, etc.) holding it on but friction, I would apply a penetrating oil and let sit for a while. Tapping with a non marring hammer may help the oil to penetrate. Then you could slip a rope through either the hand guard or the upper and then tie it to a tree, post, etc. and give it a good jerk. Or apply pressure--pull--and tap with a non marring hammer to set up a vibration.
Maybe slip a spacer/wedge between where the bolts clamp it together.
Try twisting the 2 parts if there aren't any limiting pins or bumps.

[baih777]

Are you sure it's not threaded on? The pinch bolts hold it in position ?

[lt05deluxe]

Try twisting it off.

[yrs]

Are you sure it's not threaded on? The pinch bolts hold it in position ?

I'm sure it's not threaded on. It's a slim profile handguard contoured such that only the topside has room for the gas block. So it cannot rotate completely.

If you're completely sure that there is nothing (bolts, pins, etc.) holding it on but friction, I would apply a penetrating oil and let sit for a while. Tapping with a non marring hammer may help the oil to penetrate. Then you could slip a rope through either the hand guard or the upper and then tie it to a tree, post, etc. and give it a good jerk. Or apply pressure--pull--and tap with a non marring hammer to set up a vibration.
Maybe slip a spacer/wedge between where the bolts clamp it together.
Try twisting the 2 parts if there aren't any limiting pins or bumps.

Thanks for all the tips. I'll start trying some of these.

[ar15barrels]

Heat makes aluminum expand very quickly.
Heat the rail around the barrel nut very quickly to about 400 degrees with a propane torch without heating the actual nut and receiver and it will come free before the heat all equalizes into the nut and receiver.

[pklin1297]

Have you tried asking the manufacturer of said complete upper?

I would talk to them before doing any twisting/grabbing/forcing/mutilating/heating, etc.

[Sicarius]

Bigger hammer.
Kevin