I purchased a LMT BUIS several months ago and just got around to mounting it on a Stag upper.  It fits great but I don't like the big attachment knob on the side of the sight.  

Is there a way to remove the knob and still use the sight?

Some have removed the knob, chopped the bolt, and used a hex nut.

Quoted: Some have removed the knob, chopped the bolt, and used a hex nut.

I did this with my CCH BUIS.

I’ve posted this quite a few times, once was in the thread about DIY modifications. No one ever paid much attention, I like how it streamlines the BUIS and removes some unwanted weight.

Interesting idea...

Anyone know if there is a way to disassemble the knob from the sight without cutting?

Quoted: Anyone know if there is a way to disassemble the knob from the sight without cutting?

Remove the original bolt and thumb nut and replace it with a Button head screw and nut. If you wish to return the sight to original reverse the process.

Quoted: Remove the original bolt and thumb nut and replace it with a Button head screw and nut. If you wish to return the sight to original reverse the process.

When loosening the knob it seems to have something stopping it.  For removal, do I just keep turning it to the left?

My setup is virtually the same as Quib's.

Quoted: Quoted: Remove the original bolt and thumb nut and replace it with a Button head screw and nut. If you wish to return the sight to original reverse the process. When loosening the knob it seems to have something stopping it.  For removal, do I just keep turning it to the left?

I just grabbed the sight, and twisted the locknut right off (I used pliers on the nut itself--forgot to add); it takes some force, but not a whole lot, and the threads weren't damaged at all. Once the locknut's off, install the sight with the replacement nut. I think it's an M5 (can't remember, exactly), but you can always take the sight into the store with you to make sure you get one that fits. Once the sight is installed, you just cut off the excess threads on the mounting bolt, and reblue. If you can, get a blued nut for the replacement. If you can't find blued nuts, you can carefully grind off the plating to blue it.
I think Quib and myself had the same idea at about the same time, because when I originally posted about mine, he had just gotten through doing his, also.

tag... 'cause I keep forgetting to do mine.