Suppressors Surefire Socom 762 RC2 vs Knights Armament 762 QDC Full Size

[nn8734]

Have been scouring the interwebs for some substantive information about how these two suppressors compare to each other with respect to (in order of priority):

1) back pressure management
2) poi shift relative to unsuppressed
3) poi shift when shot after heating up (poi shift for shots 9 and 10 compared to point of impact with a cold bore)
4) mounting design
5) general overall durability
6) sound suppression

Suppressor will be used on a precision AR platform that will be shot to 1000 yards
Am not interested in any other suppressors, just these two.

Looking for insight from those in the know...Thanks in advance!

 

[MOUNTIC]

Own both the 762RC and 762 QDC. They both are very good and almost identical performance. Now that I own both, I would make my deciding factory on muzzle devices / attachment method because the performance is that close I can't give it to one or another. I know that sounds kinda stupid but if you are looking to shoot unsuppressed and want a muzzle brake, KAC does not offer one other then the MAMS. The MAMS also decreases accuracy by about .2 from what I've seen. Confirmed this with KAC and they see same results. Attaching both cans with the muzzle straight up have seen better repeatable results also. The QDC attachment method is nice with the ball bearings that fall right into place and you don't have any leaking like you do with the surefire. The surefire gets some buildup around the index slot and you have to wipe down your barrel after a while. The KAC I think does ever so slightly better with flash when night shooting.

The performance of them are so close it kinda comes down to price, availability, and muzzle devices/attachment method. Some deals popup on the RC that makes it hard to not recommend.

If it's only going to be a "precision" gun and your not dumping mags or anything crazy, I would get a TB ultra instead.

For hard use gas guns, you really picked the best two options IMO. I run the cans you mentioned on KAC and LMT 308 gas guns, as more of a heavy battle rifle and use the TB cans for anything precision. For a cross over, you are in the right spot with your two choices. Just pick one and don't look back. They are both excellent.

 

[MOUNTIC]

1) back pressure management EQUAL Can't personally tell a difference
2) poi shift relative to unsuppressed EQUAL both about 1 moa low and half moa windage on two different guns
3) poi shift when shot after heating up (poi shift for shots 9 and 10 compared to point of impact with a cold bore) EQUAL. Don't notice a difference. I've shot some of my best groups on rounds 16-20 with a pretty warm suppressor.
4) mounting design DIFFERENT BUT BOTH WORK WELL
5) general overall durability YOU PICKED THE BEST TWO
6) sound suppression GOOD ENOUGH.

 

[nn8734]

Thank you @jwknutson17, exactly the sort of insight I’m looking for. The AR in question is a Knights SR25 EMR with the obermeyer match CL Barrel; this one has been threaded 3/4 x 24 by the previous owner.

Money is no object in terms of a decision (even accounting for any deals that may become available from time to time on the RC). Just want to pick the best available can for my use case(s).

While I do plan to use in a precision application most of the time, I have to also allow for possibility of hard use / lengthy courses of fire when taking classes or in competitions, etc.

For those reasons, other cans, including the THunderbeast cans, have been selected out with these two remaining.

Thanks again for the detailed replies!

 

[MOUNTIC]

If it's going on a KAC stick with the KAC. That's what I did. SR25 APC with 7.62 QDC. After all they make their cans for there SR25s in the first place!

 

[nn8734]

If it's going on a KAC stick with the KAC. That's what I did. SR25 APC with 7.62 QDC. After all they make their cans for there SR25s in the first place!

True but then again, my Mk11 Mod 0 suppressor doesn’t work at all with my SR25.

It fits loose and poi shift is massive; groups like a shot gun at 100 yards with all types of loads; those same loads shoot .75 to 1.5 MOA when rifle is unsuppressed. That can is currently with all of my Mk13 Mod 5 parts at Long Rifles for a build. Thus the need for another can; one that works as it should and doesn’t “wiggle” when mounted, lol.

Thanks again for all of the insight!

 

[MPDS13]

I cannot comment on the KAC. I only have the 762RC2. But I do love this suppressor and I would agree with everything said above. It really is one of the best suppressors, especially for a Semi-Auto. You technically may loose a couple DBs of sounds reduction due to the internal design. But the back pressure and repeatability and durability are amazing.

 

[MOUNTIC]

Here is roughly my 5 round POI shift with the SR25 with QDC can on it. It was Zeroed without the can. FGMM 175gr

 

[nn8734]

I cannot comment on the KAC. I only have the 762RC2. But I do love this suppressor and I would agree with everything said above. It really is one of the best suppressors, especially for a Semi-Auto. You technically may loose a couple DBs of sounds reduction due to the internal design. But the back pressure and repeatability and durability are amazing.

Thanks, @MPDS13, good to know...overall sound suppression isn’t a big deal, as long as the suppressor removes the concussive “BANG”. How much is the POI shift with with the can on vs off?

 

[Breacher]

I have them both also. I still think KAC has the best mounting system of any suppressor. They are very equal but the mount system of the Knights puts it on top for me.

 

[MPDS13]

I'll be honest. I do not know the exact POI shift between suppressed and unsuppressed. I zeroed with suppressor on and shoot pretty much suppressed always now. I can say that taking the suppressor on and off numerous times. There is absolutely no shift in my Zero, shooting suppressed.

 

[gconnoyer]

*Surefire RC2*
My POI shift with my bolt gun (26" M24 contour barrel) is .1U/.1L.
Attaching and removing the can POI and return to zero is perfect and consistent.

I even had to pull the can off at a match once during a stage and hit the 930y target because I knew what the offset was and it was repeatable.

 

[nn8734]

@gconnoyer,

Thanks for the response. Are you referring to the KAC 762 QDC or SF Socom rc2?

 

[gconnoyer]

Sorry, the RC2

 

[nn8734]

Would like to thank everyone for their contributions...after thinking it through, taking into account the posts above along with other research and conversations with end users of both, Ive decided to go with the KAC can.

Decision came down to the mounting system and ability to run the MAMS muzzle brake. These cans are otherwise neck and neck in terms of all the other parameters.

 

[Breacher]

Nice choice!

 

[nn8734]

@Breacher - sick rifle! Very nice. Looks to be a tan version of what I’ll end up with when my 762 qdc and stamp arrive (appx 1 million years from now).

 

[Breacher]

Thanks man. You’re going to love it.

 

[Movistar]

True but then again, my Mk11 Mod 0 suppressor doesn’t work at all with my SR25.

It fits loose and poi shift is massive; groups like a shot gun at 100 yards with all types of loads; those same loads shoot .75 to 1.5 MOA when rifle is unsuppressed. That can is currently with all of my Mk13 Mod 5 parts at Long Rifles for a build. Thus the need for another can; one that works as it should and doesn’t “wiggle” when mounted, lol.

Thanks again for all of the insight!

Bro did you call KAC? If I’m not mistaken they will swap your barrel with one that the can fits better.

Thanks for the thread guys. I’m also looking for a can for the SR25 APC and considering these two.

 

[nn8734]

Bro did you call KAC? If I’m not mistaken they will swap your barrel with one that the can fits better.

Thanks for the thread guys. I’m also looking for a can for the SR25 APC and considering these two.

Hey Movistar, called KAC about the Mk11 can and they advised sending a detailed email to their “returns and repairs” mailbox. Haven’t done that yet as my mk11 can is still with LRI but will contact Knights once I have it back in my possession.

Overall my plan is to run the 7.62 QDC on my SR25 once it’s out of jail and Mk11 can on the Mk13 once it’s all done.

 

[Movistar]

Cool man. I had an SR25 ER and a NSW return MK11 can and it wasn’t a perfect lock up but it didn’t kill my accuracy. Mine only rotated left and right at the gate where it latched. But the muzzle was concentric still. Sadly I had to sell that gun and suppressor during my divorce to pay legal bills. She is missed.

 

[nn8734]

Sweet looking set up, man. Sorry to hear of the circumstances forcing its sale. My SR25 is an EMR the prev owner had Nefarious Arms dimple the barrel and trim to 18.5”. I have owned it for a year and recently added a long tine MAMS and LMT stock kit.

 

[Movistar]

Sweet looking set up, man. Sorry to hear of the circumstances forcing its sale. My SR25 is an EMR the prev owner had Nefarious Arms dimple the barrel and trim to 18.5”. I have owned it for a year and recently added a long tine MAMS and LMT stock kit.View attachment 7164669View attachment 7164670View attachment 7164682

What gun are you putting the MK11 suppressor on?

The EMR is cool. I’d have that baby chopped to 16 since it’s dimpled

 

[nn8734]

Mk11 suppressor is going on the Mk13 mod 5 under construction with Long Rifles.

Thought about going to 16” (and still may) but like the 2550 ft/sec I’m getting with my 175 SMKs over 41.1g of IMR4064. Where I’m at, it’s supersonic to 1250 yards.

Which one of the two cans (762 QD or Surefire RC) are you leaning toward?

 

[Movistar]

Did you put the MK11 cab on the 18.5 inch gun? Is that when it was wobbling?

 

[nn8734]

Did you put the MK11 cab on the 18.5 inch gun? Is that when it was wobbling?

Yep, put the Mk11 can on the 18.5” barrel...the can wobbled from side to side laterally (if standing in front of the rifle with the Mk-11 can on, you can rotate it left-right by appx 1/64 of an inch. It doesn’t lock up tight...There was no play vertically.

I figure the barrel has to be the full 20” for it to work properly although a KAC rep told me that shouldn’t matter.

 

[Movistar]

Oh for sure. The way that can works there’s spring loaded tabs that push on the end of the barrel to lock it in. That’s 100% why it wobbles is your barrel isn’t long enough. If you look close at the end of the mK11 or ER barrel you’ll notice that the last 1/2 inch of barrel is slightly larger than the next 4-5 inches of barrel. The hole in the inside of the suppressor it meant to fit that size and then be the right length. So it fits in two ways. The first is length because the crown pushes against the springy tabs and second is width of the barrel at the muzzle to keep it from moving. Both the width and length of the barrel have to be right. It’s why LRI will “fit” the can to the barrel of your MK13. Most the the exposed barrel is .735 but the last half inch or so at the end is .750. If it isn’t exactly right then the suppressor won’t work. I can’t believe it didn’t blow up if you put rounds through it. Crazy lucky. The internals of the M110 and MK11 cans are very different. I noticed an M110 flash hider in your pic.

If I was you since you have the can going on the Mk13 I’d chop this gun down to 16 and roll like a M110K1.

 

[nn8734]

Yea true. Or at the very least. baffle strikes (I confirmed no baffle strikes either with a bore scope)...Makes perfect sense as to why it was behaving that way. Was almost positive the barrel being altered was the problem. You can even see the last half inch of the barrel looks different (looks slightly “lighter” in color) in numerous pics of other unaltered mk11s. Thank you for confirming with the specifics.

I may chop to 16” as it definitely would make the weapon handier and prob wouldn’t lose much on MV. Plus it would be very similar to an M110K1 like you say...Gun would still be fine to 800 which is all I really need insofar as effective range.

 

[Movistar]

Yep. The M110K1 is 16 inches and honestly that’s plenty for 800. You’ll have the sick MK13 for anything longer too. Can’t wait to see it when it’s done.