Guys, I'm testing an UltraSlim Crush Washer to mate with our Alpha, Bravo, and Delta line of UltraSlim muzzle devices so that they can be timed.
Got three stainless steel metal 3D-printed prototypes suckers cost $50 each! of my UltraSlim crush washer design and am testing its installation. Results, so far, are mixed. Have gotten 90° rotation, but the outside diameter (OD) enlarged such that I can't slip a standard .750 gas block on and off which was one of the goals. Also, I thought the torque force required for this smaller washer would be less, but it stills seems like I'm cranking it a lot toward the end.
Trying to decide whether pursuing this UltraSlim crush washer is the best method or whether I should pursue UltraSlim sets of super thin shim washers.
Some say crush washers can induce cant to your muzzle device, causing inaccuracy and potential strikes (if using with longer devices like suppressors), and that they're not reusable like shims when one wants to remove for cleaning. Others say shims are too fiddly.
Attached photos show the three stainless UltraSlim crush washer prototypes and a standard 5/8 crush washer (Yankee Hill).
Anyway, what you guys think? Crush washer or shim set? Pros and cons?
My gut says that shims would be best for alignment and too fiddly, but I'll deal with fiddly for it to be as square to bore centerline as possible how often will I be R&R'ing it in the big picture...
Why 3D print the washer prototype? I ask this because a 3D printed ss washer will not react like a spring steel washer. You can get hand made spring steel prototypes made for a little more cost, but would give a better correlation. The 3D printed great for visual in this case, but a hand made spring steel better for proof of concept. Or is the 3D printed the production intent?
Again just my 2cents. If you can get a sheet of untreated spring steel in the thickness you want. You can punch out the ID and OD, shape the bevel with a punch and socket, then heat harden it to put the spring into it.
Never thought of doing it that way. That assumes one has the skill to do all that. Which I don't. I suppose I could try my hand at butchering it, but that still wouldn't give a very close approximation of the actual part. This kind of crush washer, because of the bevel, can't be stamped, it has to be machined, as are all AR15 crush washers. I researched it and that's what I was told.
:: 6.5 GRENDEL Deer and Targets :: 6mmARC Targets and Varmints and Deer :: 22 ARC Varmints and Targets
I would think laser cut stainless shim stock would be the most cost effective way to go, 24 TPI is .083" and change so a .020", .040" and a couple of .005" would likely get the job done.
eggman918 Wrote:I would think laser cut stainless shim stock would be the most cost effective way to go, 24 TPI is .083" and change so a .020", .040" and a couple of .005" would likely get the job done.
eggman918 Wrote:I would think laser cut stainless shim stock would be the most cost effective way to go, 24 TPI is .083" and change so a .020", .040" and a couple of .005" would likely get the job done.
One divided by twenty-four (1/24) is .042. Correct me if my math is wrong, but with 5/8-24 threads one complete 360° rotation should result in linear movement of .042? Thus, at a very worst-case scenario, one needs a shim set with a total thickness of .042 (in practice, probably no more than 180° rotation, .021 linear travel, would be needed). Right? Or am I missing something?
:: 6.5 GRENDEL Deer and Targets :: 6mmARC Targets and Varmints and Deer :: 22 ARC Varmints and Targets
The first AR I ever owned had an A1 muzzle brake. I wanted to change it to an A2. I used a peel washer to get the A2 timed. No crush washer, no jamb nut ... just enough washer layers to get the job done. Now days I'm using Precision Armament's ACCU-WASHER System washers for timing muzzle brakes.
BluntForceTrauma Wrote:Never thought of doing it that way. That assumes one has the skill to do all that. Which I don't. I suppose I could try my hand at butchering it, but that still wouldn't give a very close approximation of the actual part. This kind of crush washer, because of the bevel, can't be stamped, it has to be machined, as are all AR15 crush washers. I researched it and that's what I was told.
There is no doubt that you have the skill. You just have not found it yet.
BluntForceTrauma Wrote:Never thought of doing it that way. That assumes one has the skill to do all that. Which I don't. I suppose I could try my hand at butchering it, but that still wouldn't give a very close approximation of the actual part. This kind of crush washer, because of the bevel, can't be stamped, it has to be machined, as are all AR15 crush washers. I researched it and that's what I was told.
If you have a drawing of what you want I'll make you a couple out of either 1045 or 304 SS as I have that on the shelf, then you can tinker with them to decide if you like them.
I have all the time in the world and the machines needed to do them, less that an hours time so at your service if it will help the cause.
Old Bob Wrote:Now days I'm using Precision Armament's ACCU-WASHER System washers for timing muzzle brakes.... I just snug up the brake with the correct thickness washer to get proper timing ... might be just a hair more than hand-tight. Not heavily torqued.
Bob, any problems with the muzzle device rattling loose, or does your just-snug-enough torque keep it in place?
:: 6.5 GRENDEL Deer and Targets :: 6mmARC Targets and Varmints and Deer :: 22 ARC Varmints and Targets
Talking about muzzle devices coming loose, back in the 80's it was split washers, not crush washers.
The original A1 flash hider did not need to be timed as it had six evenly spaced slots (no A2 dust signature section), so used a split washer for keeping it on. Modern brakes that do not need to be timed can also use an A1 split washer, hand tight only - and they do not come loose. This also helps with cleaning the crown after shooting as unscrewing a split washer is not a once-only situation.
eggman918 Wrote:I would think laser cut stainless shim stock would be the most cost effective way to go, 24 TPI is .083" and change so a .020", .040" and a couple of .005" would likely get the job done.
JASmith Wrote:That might work!
Old Bob Wrote:The first AR I ever owned had an A1 muzzle brake. I wanted to change it to an A2. I used a peel washer to get the A2 timed. No crush washer, no jamb nut ... just enough washer layers to get the job done. Now days I'm using Precision Armament's ACCU-WASHER System washers for timing muzzle brakes.
