tighten the carry handle on the m4

[ridgerunner70]

how tight should the bolts be torqued on the carry handle?

[Iraqgunz]

You shouldn't have to tighten them more than finger tight.

[ST911]

Thumb screw, thumb tight.

[JSantoro]

^^^This. If you're feeling puckish and want it tighter, go to finger-tight and add 90deg with a tool in the slot of the thumbscrew...but be prepared to carry that tool with you if you ever need to get it off for some reason or another.

Whether you go finger-tight or a bit extra, use a paint pen or something to make witness marks on the screw and the interface they're mounted to so you have a visual indicator of where they ended up. That way, if they back off, all you have to do is re-tighten to the witness marks. That gives you the consistency you need to ensure that you maintain whatever zero you end up putting on that thing, whenever you have occasion to remove/reinstall the carry handle.

[Quib]

[tracker722]

******

[armakraut]

Do they actually stay tight over time like that?

The only time I never used loctite on an ACOG scope mount, it was flopping around by the 2nd mag.

[GeorgiaBoy]

Do they actually stay tight over time like that?

The only time I never used loctite on an ACOG scope mount, it was flopping around by the 2nd mag.

I hate being a necroposter, but I am very interested in this.

I would think that with all the loctiting/tourqing/ect. that is always recommended with the AR platform would carry over to things like carry handles. It kind of surprises me that a SIGHT should only be "hand-tightened" on...

What exactly keeps it tightened? How do you know that the screws don't back off? If they back off, and are re-tightened, can this affect your zero?

[GTifosi]

'Usually' mounting such items calls for tightening down, firing several rounds, then tightening again.

Doing such, for want of a better phrase, shakes the loose spots out where things might not neccisarily be fit as well as they could be with the initial tightening.

Done properly loctite or whatever isn't needed.
Provided of course the screws and nuts are of a a quality make and material.

FWIW I take the easy way out becuase I have spastic fingers: penny tight, nickle loose.
As in never use anything tougher or bigger than a penny to do the tightening on the slotted nuts. The penny will bend if you get too tight giving a decent indicator that you sould probably stop there.
Using a nickle to loosen will always overcome the penny due to the size, and thus leverage, difference.

Removal, retightening, etc. and maintaining zero is a function of mount quality and rail quality.
If all are in suitable spec then there won't be enough room for things to shuffle enough to lose zero.
Sloppy rails and mounts make for sloppy affixment and inconsistant zero retension.

[everyusernametaken]

I use a nickel for both tightening/loosening on my ACOG and carry handle, whichever I'm using at the time. I never have any loosening whatsoever, even over a couple hundred rounds in a single session.

After positioning whatever I'm mounting on the rail, I apply downward and forward pressure on the scope/handle against the rail grooves, while tightening the screws to finger tight. This always aligns the device precisely the same from one time to the next, and I often don't need more than maybe one click adjustment of the scope to get back to perfect zero. Last time didn't even need one click.