Long time reader, first time poster. Bought a b&t rotex x compact with a qd mount for a standard A2 cage. Bought the accu washer kit to replace the crush washer. After following the instructions I'm either just shy or just past dead center. I'd say ten degrees or less either way. Is this an issue or am I over thinking it? I've tried searching the forum and googling it, but can't find much info specifically about the A2 as a suppressor host. I'll attach a photo below. I stuck a couple earth magnets on the flats to give a bit of a visual cue to try and make it easier to see. Just trying to figure out if I'm gonna be fine, or if I need to pull everything off and start over with a different shim kit.

Nevermind, can't figure out how to upload a picture on the site, and imgur is down at the moment. Basically if proper orientation is 12 o'clock, mine is eleven o'clock or eleven thirty. Hopefully my description helps. I'll try to post the photo again tomorrow.

As a righty, I don’t mind when my A2s end up just short of perfectly timed.

Do you have feeler gauges?
Loosen until you're timed, so 11.5hrs back.
Insert feeler gauges to get gap
Insert the shim or combo to that gap size.
Due to torque setting, you might want to add 10 or so degrees of timing (increasing shim gap)

Assuming you don’t have any room for different torque applied, then 10 degrees is only 0.001” of shim thickness for a 28 tpi thread pitch. I could accept within 10 degrees for an A2.  If you have both patience and OCD you could try sanding or stoning off a thou from the too-thick shim.

Math: 1” / 28 threads = 0.0357” of linear movement along screw for a full rotation. Every clock position is that thickness divided by 12 or about 0.003” per 30 degrees. So 10 degrees is close to a thou.

Holding a thin washer flat against a stone or sand paper on flat glass is tiring and sanding off 0.001” is slow going. You could sand the rear of A2 since it’s easier to grip (but harder to keep flat) but that leaves un-coated metal.

Do you have a torque wrench?  Doesn’t look like Precision Armament gives a specific torque range in the instructions, but Surefire says to install muzzle devices between 20-30 ft-lbs.  I would see which accu-washer allows you to get the A2 at 12 o’clock within that 20-30 torque range.

This is the problem with A2 mounts. They require a shim instead of a crush washer. You might as well just use a suppressor mount.

And good luck using an A2 for anything other than 5.56mm. Many are not mil-spec.

Shims with .001” difference will be twice as accurate as accu-washers. Some info here… https://www.ar15.com/forums/armory/Do-we-have-favorite-shims-/20-539925/

A set of shims is so cheap, you can probably get a set for free off a friend, and they come with A2 mount cans.

Most A2s (all that I’ve checked) will easily pass a .308 projectile. The 1/2x28 thread is the limiting factor, though some larger bore barrels come that way, too.

Appreciate the replies. I do have a torque wrench. I think the limiting factor for me is the twenty degree increments the accu washer kit uses. Biggest question I have as a complete noob to the suppressor game, is whether or not the slight variation in question is enough to cause me problems, specifically non repeatable poi, and worst case, damage to the rifle or suppressor. I understand that with an A2, improper alignment can cause muzzle rise and piss poor accuracy, but seeing as how the solid "bottom" is very close to where it should line up, not sure if it's going to be a problem. I appreciate the patience on this. Trying to learn. Normally I have my ducks in a row prior to jumping into something like this, but with wait times being so quick, I jumped in head first as to not risk things changing back to the long wait times of the past.

I think you’ll be functionally fine within 10 degrees.  

As long as it’s not a pin & weld job you can fix it later with different shims, different torque, light torque with rockset, finding a machinist to make a custom spacer or kiss the back of the muzzle device by facing on a lathe.  

Until you know your can QD mount fits your A2 to your satisfaction and you test everything out I’d say good enough for the time being.

Non issue.

Great that's what I was hoping. Again, thank you all for the help. Still learning and figuring things out along the way. Just trying to avoid mistakes that could cause unnecessary headaches.

It’s an incredible workhorse.