I am looking for a good QD mounting option to mount my Primal to both my .458 socom 5/8-32 and my 8.6 Blackout M18-1.5. I run Q plan B's on a couple of my other cans and planned to go that route but Q isn't making the larger size plan b yet so my 8.6 cherry bomb is basically a thread protector. Deadair sells both a Keymo mount in m18-1.5 .338 bore, and 5/8-24 7.62 bore mount. I planned to use a thread adaptor and bore to .465 for my .458. Here is the issue, the m18 .338 keymo mount doesnt index off of the shoulder it has to index off of the crown and according to the email response from Dead Air isn't capable of being clocked. My plan as of right now is to lathe material off the face of the mount until it clocks in the right position but I would love some input. I have the ability to direct mount but DM almost always needs tightened and a good QD mount stops that issue.
- Thread starter KansasCityCam223
- Start date
I would look at Rearden MFG for a Q Plan B style mount that's executed better.
They sell muzzle devices with large apertures for the bigger cartridges.
They sell muzzle devices with large apertures for the bigger cartridges.
@KansasCityCam223 can you school me on the Shoulder vs crown index advantages?
I’ve got a primal in jail and am working on an 8.6 build so keymo was my planned easy button, but was also considering direct thread adapter as well.
If there’s an inherent disadvantage with keymo in this application that may certainly sway me.
Thanks in advance!
I’ve got a primal in jail and am working on an 8.6 build so keymo was my planned easy button, but was also considering direct thread adapter as well.
If there’s an inherent disadvantage with keymo in this application that may certainly sway me.
Thanks in advance!
literally every other muzzle device I own that needs clocked indexs off the shoulder and comes with shims to put the 12ocloch ports at 12. The advantage of shoulder (behind threads) vs crown (infront of thread) is you can't use shims if it bottoms out on crown.
I would look at the ASR mounts. There is nothing wrong with a direct mount other than the can will tend to loosen and a loose can cause baffle/endcap stikes. I love the way my surefire mounts and that is what I was hoping for with the dead air. The only disadvantage I see with the DA is your muzzle device will look stupid with the 12oclock position being at 9.
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What about Ruggeds new R.U.M. system? It works with there M3 brake which is .338 compatible.
At this point I'm happy with my choose of the dead air QD muzzle device. I don't think most people would be comfortable with boring out a 7.62 for a .458 socom and removing some material to time for a 8.6 blackout. I bet we wont see many Dead Air Keymo's on Faxon 8.6 barrels
Rearden has muzzle devices with .375 and .50 apertures.
8.6mm = 0.339 inches.
My issue was I needed the same QD manufacture that I could run on my 5/8-32 and my m18-1.5. Reardens 8.6 option was not on their site when I ordered and is currently out of stock.
you've got a shoulder there to shim off of, so my first thought would be to turn a custom shim. previously all the dead air keymo stuff has come with a shim set to work with, not sure why the .338 wouldn't do the same.
I found ACC makes shims but since DA told me not to shim it I went other route. I could have mounted it with a shim for looks and still indexed off the crown but to me no shim looked cleaner.
So Dead Air doesn't provide any shims for a muzzle brake that needs to be timed?
That's bizarre.
I agree with Dead Air that shims aren't the most desirable way to time a muzzle device - it brings in factors that can potentially cause misalignment, there isn't any other good ways of timing a device without a gunsmith/machinist threading the barrel to "clock" the brake in place.
I wouldn't be afraid to use shims. But because this apparently goes against Dead Air's advice, I would do my due diligence to ensure that once the muzzle device is in place and timed, that thr barrel and mounted suppressor are aligned to make sure there's no potential for end cap strikes. Use an alignment rod.
That's bizarre.
I agree with Dead Air that shims aren't the most desirable way to time a muzzle device - it brings in factors that can potentially cause misalignment, there isn't any other good ways of timing a device without a gunsmith/machinist threading the barrel to "clock" the brake in place.
I wouldn't be afraid to use shims. But because this apparently goes against Dead Air's advice, I would do my due diligence to ensure that once the muzzle device is in place and timed, that thr barrel and mounted suppressor are aligned to make sure there's no potential for end cap strikes. Use an alignment rod.
Im not sure where my first pic went but I don't think every shim in the pack would have been enough. It looked like an 1/8" gap
I ended up going with the Area 419 Sidewinder for my 8.6. It has a nice taper to it for repeatable accuracy but no locking collar.
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eesh. that’s the point where I’d get on my own lathe and make a threaded ‘collar’ to effectively bring the shoulder up to the timing position
I thought about that but dead air said it was designed to "index on the crown". That is why I ultimately left the shim off in the end. If you have a lathe cut the QD imo. I have a couple hundred through the QD without a can and haven't had any issues yet. I like it a lot because I know we won't see alot of them on 8.6"s.
If there's available options in .30 for you guys that work ...... just drill/mill them out for .338 cal
Yall ever try those precision shim kits for timing qd breaks? I don't really worry about my yhm breaks because I always have a can on it and I've used regular shims too but I've almost gotten that precision shim kit to try out. Not sure how many of those I'd need to do all my rifles though and I don't really like using shims on can mounts but those precision seem like a good idea?
Have you guys seen JMAC/Faxons offering? Q also sells an adapter to make a 90° face for a brake to seat on. I picked up a direct thread adapter but it’s eating me up having to swap between it and my keymo adapter when I want to move my hybrid46 around
faxonfirearms.com
liveqordie.com
360 M18-1.5 Taper KeyMount (KeyMicro)
At Faxon Firearms, we pride ourselves in creating quality parts and firearms. Trust our years of experience when buying your next barrel, bcg, or complete rifle.
faxonfirearms.com TAPER ADAPTERS
Does your barrel have a tapered muzzle shoulder but you need to use shims for your muzzle brake? Do you use silencers that requires a 90° square shoulder?
liveqordie.com Have you guys seen JMAC/Faxons offering? Q also sells an adapter to make a 90° face for a brake to seat on. I picked up a direct thread adapter but it’s eating me up having to swap between it and my keymo adapter when I want to move my hybrid46 around
360 M18-1.5 Taper KeyMount (KeyMicro)
At Faxon Firearms, we pride ourselves in creating quality parts and firearms. Trust our years of experience when buying your next barrel, bcg, or complete rifle.
TAPER ADAPTERS
Does your barrel have a tapered muzzle shoulder but you need to use shims for your muzzle brake? Do you use silencers that requires a 90° square shoulder?
Faxon barrels come with a taper to 90 spacer for just that reason. The issue is Dead air Keymo .338 is made to bottom out on the crown not the shoulder. Q sells the large cherry bombs but not the large plan b's
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Been there done that with direct thread. DT is a fine option if its dedicated to 1 but the hassle of always checking the make sure its tight sucks if your not rocksetting it.
I have no doubt that if you emailed Faxon and let them know you didn't receive an adapter ring, they would send you one for free.
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