Installed my flash hider with a new crush washer and only had to tun it a little more than an eighth of a turn to get it to line up. It’s a standard A2
Is that enough?
should be fine. Use a torque wrench? get a reading?
If you’re not using it as a suppressor mount I wouldn’t worry about it. I’m having the opposite problem with an upper and am having to file down the crush washer.
c. When using a constant torque washer, replace the compensator as follows:
(1) Install the constant torque washer on the barrel with concave face facing the
compensator;
(2) Screw the compensator on until it contacts the face of constant torque washer; and
(3) Use the combination wrench and a 1/2 inch drive ratchet to tighten the compensator 90° minimum to 460° maximum, from first contact; or
d. When using a laminated compensator spacer, replace the compensator as follows:
(1) Install the compensator spacer on the barrel with the laminations facing the
compensator;
(2) Screw the compensator on hand tight; and
(3) Use the combination wrench and a 1/2 inch drive torque wrench to tighten the
compensator to a torque of between 62.4 and 69.1 N·m (46 and 51 ft-lb).
NOTE
If upon installation and torquing the middle slot of the compensator is not uppermost and aligned with the front sight, remove the compensator and reduce the thickness of the compensator spacer by removing sufficient laminations to facilitate correct alignment after torquing is carried out.
If you can’t remove it by hand you’ll be alright although its not the by the book way QUIB posted. Not a lot of people have all the tools and blocks needed to get that specific of a torque measurement.
If you are using a can with it you shouldn’t be using a crush washer in the first place.
Quib,
The TMs That I have seen say that when useing a peel washer to torque the FS to 15-20 Ft. Lbs.
I’m at the office at the moment, and don’t have access to my TMs.
I pulled that reference off line here:
MAINTENANCE INSTRUCTIONS
C7 FAMILY OF COMBAT WEAPONS
http://http://www.coltcanada.com/techpubs.htm
ETA: You’ll find this torque called out at:
- Figure 3-1-1 Torque Limits
- Page 3-2-15
I’ll agree that torque seems high and contradicts the -23 torque.
TM 9-1005-319-23&p dated 1987 has the torque range from 15-20 ft-lb. Page 3-44. I can’t find peel washers in the latest change 8 TM.
This is the procedure for installing a FH with a crush washer.
NOTE
Recessed washer does not require torqueing
- Assemble compensator to the barrel
using recessed washer (12991533) (fig
C-6, item 5) with the large diameter of
the recessed washer forward toward
the compensator and the small
diameter rearward toward the barrel.
Tighten the compensator hand tight and
then tighten a minimum of ¼ turn but no
more than 1 ¼ turns to align the center
of the middle slot (4) with the front sight
post (5). Tighten the compensator to
complete the alignment with the front
sight post. Do not over rotate. If the
compensator is turned backwards, the
compensator will loosen, so the
procedure must be started over with a
new recessed washer.
Discontinued perhaps.
ETA: -23&P W/C 8: Figure C-7 of the IPC covers the FH installation. The latest change to affect that figure was Ch. 7. Could be that change or a change prior to 7, deleted the peel washer.
A minimum of 1/4 turn so I’m not there. I can’t go a full revolution, I don’t a big enough vice.
Any suggestions on how to get it tighter without sending it to some one?
File the crush washer or pre crush in a vice until I can get half a turn on the flash hider. neither sound good to me.
Thanks for all the help
A little off topic but, where can you get a constant torque washer? TIA
Nothing more than a standard crush washer. Any AR parts vendor will have them.
Im with Belmont31R… “If you can’t remove it by hand you’ll be alright…”
DO NOT try to go another full turn from where it is now. 
Some worry about needing to apply too much torque to properly time their FH which can lead to loss in accuracy, from what Ive gathered.
My guess is, youve probably hit the minimum of the torque range. – a sweet spot IMHO.
Just to address your question… From my little personal experience, filing would be the best way to go. Slow and tedious but the smarter way to go.
Pre-crushing with a vise may lead to over crushing (like it did mine) in which case, you’d go past alignment and have to file it down just to get it back to pre-alignment. But again, yours is GTG to me.
Just a thought but you could install a flat washer(s) to take up some space before installing the crush washer to get the correct alignment.
You shouldn’t need to use a flat washer to get it to line up properly. Once you add a flat washer you will probably change things. This was part of the problem with the old peel washers.
LOL, I can see why the peel washers were discontinued… what a pain in the ass they make trying to install and time a FH.
25 years in aviation maintenance, I’ve dealt with my share of components requiring fitting and installing of shims. Timing a FH with peel washers ranked right up there with the best!
Quib,
Thanks
Well I was able to take it off with just my hands…crap.
file file file… almost there… just a little more…perfect
Wouldn’t filing it make it looser? Unless you are taking off enough to go through a complete 2nd turn…?
This is why I buy about 5 washers here and there. Just a slight variation between each one can make a headache turn into bliss. Just try different combo’s until one lines up correctly without over torque or under torque.
My simple rule is a bit beyond hand tight is fine. I know its not by the book to the exact TM but it will do fine for 99% of the time. Ive never had one come loose or do anything but work as intended.
Just a bit of an FYI but you can spend 100-200 bucks and have tons of spare parts to keep on hand. Its a worthy investment as its a PIA to have to wait on a part to get your gun running or do some maintenance. Keep some gas rings, extractors, recoil springs, end plates, CH’s, a bolt or two, firing pins, cotter pins, cam pins, etc. Just having spare parts has “saved the day” for many an AR enthusiast. Even 50 dollars a month to small parts is worthy, and in a few months you will have almost anything you can think of to replace at the operator level. I also keep a couple spare lower parts kits around. Those little springs and detents like to do the pole vault never to be seen again…
Yes took off enough to go around again.
I do have a spare parts kits and I measured all my crush washers and they are .150-.153 thick.
First time something like this has happened.