Gunsmithing Round Bushmaster Handguard Removal help needed.

[338LM_Sniper]

I picked up a 450 Bushmaster complete 20" Upper from another member on the Hide a few months ago. I just put it on a lower and installed my Harris Bipod and noticed that the hand guard is not centered to allow the bipod stud to be at the bottom position. It is off about 1" and I want to loosen up this hand guard and make it so that the bipod stud is at 6 o'clock proper position. Now I am not sure how to remove or loosen up this Handguard as it looks like it has a ring at the bottom near the receiver that I believe needs to be loosened up. Can someone tell me which part on this Handguard that I need to put my Strap Wrench on looking down the barrel from the muzzle and in which direction do I turn it? I just don't want to damage anything here.

Also will I need to heat this up? See Pics of Handguard below.

Thanks for any help here.

 

[240nmc]

Strap wrench? Leather and Vice Grips? (leather strap and two ends pinched in vice grips). Just thoughts.

 

[hlee]

DPMS uses(ed) a similar hand guard, and I had read about how difficult it was to remove. I put my upper in my barrel vice, grabbed my strap wrench, and girded my loins for the battle that was about to ensue. Once I had the strap wrench on the hand guard, it came off with very little effort. I was actually a little bit let down. And relieved. Mostly relieved. But a little let down. I say this just to ask "have you tried to remove the hand guard yet?" It may spin off with relatively little effort. Just remember, lefty loosy, righty tighty... Grab around the main part of the hand guard. My bet is that the knurled part at the rear is the barrel nut...

 

[FMJ]

If you don't want to mess with it you may be able to relocate the stud by making a new hole.

 

[kl3309]

Is the knurled part a separate locking ring? If it is, then clock-wise (looking from the muzzle end) on the ring would free up the handguard tube (which would spin off counter-clockwise).

Edit:
OK, looked around and saw that the knurled ring is a locking ring.
You can:
1. secure the receiver and spin the locking ring
2. secure the locking ring and spin the handguard
3. secure the handguard and spin the locking ring

 

[338LM_Sniper]

Well I was able to use the small strap wrench and turn the Knurled Ring clockwise and with a lot of elbow grease I got the Knurled Ring loose. Now the main tube is still tight and having the Knurled Ring loose didn't get the Main Tube loose at all? I put the large strap wrench on the main tube and turned counter clockwise with all my strength and I ended up breaking the black belt in half on the strap wrench. The Main Tube is still locked rock solid? It may have locktite on it and I may have to heat it up to get the main tube off.

What a PIA

 

[kl3309]

Sounds about typical of a factory assembled top end.
Put some heat to it but keep in mind that you'll also heat up whatever's sealing the barrel nut. Watch that you're not spinning that the barrel nut against the gas tube when you attack the handguard tube.

 

[338LM_Sniper]

I first need to go back out and pick up another strap wrench.

Thanks for all your help.