My go-to LMT/BCM/KAC 11.5 SBR build

[Jwknutson17]

So after taking some advice from BradfordTjustice on the A5 set up, I have now been converted to..... The A5H4 and LMT E-Carrier with standard BCM bolt. I have to say, that this setup just flat out works. I was hesitant to pull the trigger at first, but I am sure as heck glad I did. I also ran the E-carrier A5H4 set up in 10.X and 12.Xs and 13.7 all suppressed rifles. I think I'm fully converted, but need to send a few thousand more rounds down range before I put all my chips in the same bag. The A5H3 felt pretty good, but throwing the 4 in there.. man, that is nice with the e-carrier standard bolt setup!!

[TF82]

You sir, have a lot of nice stuff. I'm glad you decide to sell it on the EE sometimes.

[Jwknutson17]

You sir, have a lot of nice stuff. I'm glad you decide to sell it on the EE sometimes.

Thanks. Gets expensive. But a lot of things you just don't know if you like em or not without trying them first hand. So most of the stuff that goes to EE has only few hundred on em. First hand experience is the only way. Something can get the best reviews but you just don't know until you personally field it. Unless you have a bunch of buddies with similar tastes or hit a lot of classes. Thanks for the compliments.

[Jwknutson17]

Update on the SBR.. Few things have changed.

-Geissele SSA now is replaced with the Geissele SD-C (flat trigger face)

Once I tried one of the flat geissele triggers, I didn't have the slightest clue what I was missing until then. I have larger hands and the little extra reach and flat face really felt like a better pull for me. The flat/straight to the rear pull was a little easier for me. I tend to reach lower on the trigger and I still have a nice flat pull. Almost feels lighter then the SSA. Absolutely nothing wrong with the SSA or SSA-Es as I still have them on many rifles. But this trigger on the Go-to SBR just feels right.

-Vltor A5 System and E-Carrier.

With insight from BradfordT and others with success on this combo, the rifle runs cleaner and just feels better suppressed.

-KAC MAMS and QDC Suppressor replaced the Surefire Brake and RC & mini

While I absolutely love the SOCOM series suppressors and for the money I would say they are still the best in the biz. I have a KAC QDC CQB suppressor also on hand. As this is my Go-To training, HD, etc etc rifle, I have been doing a lot more un-suppressed shooting and using the rifle in classes, etc, etc. The MAMS is considerably less evasive on a 11.5 then the Surefire brake. I also have been using the SOCOM mini a bit more then the RC. Even though it was only an inch or so, getting in and out of the Polaris and the truck made it marginally easier. Probably in my head but never the less its shorter. With the MAMS still even shorter and 3.8oz lighter (MAMS and Suppressor combined) and I feel has slightly less flash then the socom Mini, but comparable performance, with the rifle being used more unsuppressed, I felt the best option was switch to the MAMS and QDC suppressor. Also I carry it through the woods on the property a lot. With all the garbage and suppressor strapped to this thing, it adds up in weight.

-KAC Front sight made it on the rifle.

After using the CQBL-1 as my backup, in the day time more then 30 yards was really not a viable BUIS option. It was too hard to see. Night was no issue. Day time didn't work that well. As the M4s would most likley never fail, I decided to run BUIS's also for peace of mind. All my rifles had them but this one. The switch coming unplugged on the laser under fire was previously an issue that was remedied with a rubber band, the KAC micro sight installed flipped around, perfectly touches the plug and does not come out no matter what round count or recoil. The only issue this brings up is that the front sight has to be removed to replace the CQBL-1 battery. I tested POI from removing the sight and installing and constantly within 2moa of previous zero. I had to move the SR-D-IT switch back 2 notches for the KAC iron front. The front sight is in the fixed upwards position and will stay that way.

-Bobro mount replaced with ADM

This was not my plan. I love Bobro mounts. But with the rail space it takes up and with wanting to run PVS-14, I needed the little bit of cantilever mount on the optic. I had an M4s with ADM mount, so optic and mount switched with another rifle. It gives me enough space to still have my rear sight and the optic in desired position and add my magnifier if needed or PVS-14s when needed.


That's it for now.. The continued evolution of the rifle. It truly never ends. But I have to say this thing runs and runs. And with my new found love for Fireclean, it is a lot easier to run it hard and clean up after. The second to last pic is this MAMS with Aprox 800 rounds on it after it was cleaned up with fireclean. The KAC MAMS directs some of the bast towards the mounting surface on the KAC can/MD. When NOT using fireclean after a few hundred rounds it would become harder to remove and have to yank the can off. Now with the fireclean, I don't have this issue. (was mainly on heavier rate of fire) See the last photo for the MAMS where the arrow is pointing. This is on another one of my rifles. Where it is scraped off at the arrow is where the carbon builds up. This was without fireclean and needed a carbon scraper.

[jerrysimons]

Great rifle! Thanks for the write up. Good thoughts on the KAC QDC CQB set-up.

[Jwknutson17]

Great rifle! Thanks for the write up. Good thoughts on the KAC QDC CQB set-up.

Thanks! I have been pleased with the KAC QDC CQB so far. The only issue that I had was the carbon build up preventing the can to come of easily. Also needed some Mil-comm white grease on the ratcheting teeth if that's what they call it.. After 300-500 rounds the locking collar that twists got really stiff. Had to heat the thing up with a quick mag dump to get it to spin easily. Not sure how much of the gasses come past taper mount area and out through those ball bearings/back of the can, but enough to build up on the side of the shims you can see in the last pic in the above post. One thing I do prefer is still the Surefire SOCOM mounting system. The KAC has the ball bearings that go into the detent holes in the MD. This does not give you the pressure holding the can on to the taper surfaces of the MD and suppressor. IMO leaking some of the gasses back through the surfaces causing them to carbon together if you will. The surefire essentially has the same taper mounting surfaces.. but the surefire collar attaches by applying force to the back of the MD with its off axis twisting motion, holding the 2 surfaces tight letting less gasses back through.

The KAC mounting tapered surfaces are essentially in/right at the blast chamber, while the surefire is all the way in the back farther away from the ports. In my experiences, you have to shoot 4 times more in the surefire to get the carbon there as the KAC. With the KAC flash hider, I have had way way less carbon then with the MAMS at the taper point. Pic below kinda shows what I'm talking about.. The surefire has about .7 inch advantage over the KAC in distance from the taper surfaces into the blast chamber. I don't know if this is the reason, but seems like a contributing factor in my book with the close distance and the ports angled back.. I am interested in the Warcomp also as the ports on those are supposedly angled like the MAMS but the warcomp has no sacrificial baffle..

[Benito]

I choose the MB's for many reasons. With being a 11.5, I do like the extra blast baffle if you will. I have eroded a few muzzle brakes on shorter SBRs down quite a bit and the baffle on even my suppressor for my 10.3" rifle still looks new after a ton of rounds. Cheap insurance for the can I guess you would say. Also, I like the way the rifle tracks and virtually no movement on target for follow up shots. I do not shoot suppressed all the time, and I notice the performance difference with the MB over the FH. If I want to, not blow away my shooting partners, or have less flash, the suppressor goes on, and problem solved. I guess if I didn't have a suppressor and was worried about muzzle flash, I would have gone with a FH. I also do not shoot indoors much. And defiantly not without the suppressor on. And just for another dumb reason that really has no merit at all, is the FH ping

On another note that pertains to your question is the new Surefire Warcomp. I will be seriously considering trying one when they are available. Only downfall with it, is I will lose my extra baffles before the can.

I am curious what your (and others') experiences/thoughts are on compensators vs brakes as far as taking some of the blast away from the can's baffles. I know that brakes will take more, but will a compensator still help in this regard?

You mentioned the Surefire WarComp:


I have been eyeing Griffin Armament's FlashComp, as it seems like it would help rapid follow-ups, while not having all of the concussion/blast of a brake :

Update on the SBR.. Few things have changed.

-Geissele SSA now is replaced with the Geissele SD-C (flat trigger face)

Once I tried one of the flat geissele triggers, I didn't have the slightest clue what I was missing until then. I have larger hands and the little extra reach and flat face really felt like a better pull for me. The flat/straight to the rear pull was a little easier for me. I tend to reach lower on the trigger and I still have a nice flat pull. Almost feels lighter then the SSA. Absolutely nothing wrong with the SSA or SSA-Es as I still have them on many rifles. But this trigger on the Go-to SBR just feels right.

-Vltor A5 System and E-Carrier.

With insight from BradfordT and others with success on this combo, the rifle runs cleaner and just feels better suppressed.

-KAC MAMS and QDC Suppressor replaced the Surefire Brake and RC & mini

While I absolutely love the SOCOM series suppressors and for the money I would say they are still the best in the biz. I have a KAC QDC CQB suppressor also on hand. As this is my Go-To training, HD, etc etc rifle, I have been doing a lot more un-suppressed shooting and using the rifle in classes, etc, etc. The MAMS is considerably less evasive on a 11.5 then the Surefire brake. I also have been using the SOCOM mini a bit more then the RC. Even though it was only an inch or so, getting in and out of the Polaris and the truck made it marginally easier. Probably in my head but never the less its shorter. With the MAMS still even shorter and 3.8oz lighter (MAMS and Suppressor combined) and I feel has slightly less flash then the socom Mini, but comparable performance, with the rifle being used more unsuppressed, I felt the best option was switch to the MAMS and QDC suppressor. Also I carry it through the woods on the property a lot. With all the garbage and suppressor strapped to this thing, it adds up in weight.

-KAC Front sight made it on the rifle.

After using the CQBL-1 as my backup, in the day time more then 30 yards was really not a viable BUIS option. It was too hard to see. Night was no issue. Day time didn't work that well. As the M4s would most likley never fail, I decided to run BUIS's also for peace of mind. All my rifles had them but this one. The switch coming unplugged on the laser under fire was previously an issue that was remedied with a rubber band, the KAC micro sight installed flipped around, perfectly touches the plug and does not come out no matter what round count or recoil. The only issue this brings up is that the front sight has to be removed to replace the CQBL-1 battery. I tested POI from removing the sight and installing and constantly within 2moa of previous zero. I had to move the SR-D-IT switch back 2 notches for the KAC iron front. The front sight is in the fixed upwards position and will stay that way.

-Bobro mount replaced with ADM

This was not my plan. I love Bobro mounts. But with the rail space it takes up and with wanting to run PVS-14, I needed the little bit of cantilever mount on the optic. I had an M4s with ADM mount, so optic and mount switched with another rifle. It gives me enough space to still have my rear sight and the optic in desired position and add my magnifier if needed or PVS-14s when needed.


That's it for now.. The continued evolution of the rifle. It truly never ends. But I have to say this thing runs and runs. And with my new found love for Fireclean, it is a lot easier to run it hard and clean up after. The second to last pic is this MAMS with Aprox 800 rounds on it after it was cleaned up with fireclean. The KAC MAMS directs some of the bast towards the mounting surface on the KAC can/MD. When NOT using fireclean after a few hundred rounds it would become harder to remove and have to yank the can off. Now with the fireclean, I don't have this issue. (was mainly on heavier rate of fire) See the last photo for the MAMS where the arrow is pointing. This is on another one of my rifles. Where it is scraped off at the arrow is where the carbon builds up. This was without fireclean and needed a carbon scraper.

Very nice changes.

I, too, really like the flat face Geissele triggers. I have one on my AR-10A. Still using conventional trigger bows on the AR-15s. Maybe will change them out, but they work just fine the way they are.

Tying into my point above, does the KAC MAMS take as much blast away from the can as a traditional muzzle brake? It kind of looks like a compensator, with numerous small holes, rather than a barge blast chamber/baffle.

Last question, both your previous can and this one, are nice and compact. Given that this is an 11.5" 5.56, does the small can (and its limited volume) bring it down to hearing safe levels?

[Jwknutson17]

I am curious what your (and others') experiences/thoughts are on compensators vs brakes as far as taking some of the blast away from the can's baffles. I know that brakes will take more, but will a compensator still help in this regard?

You mentioned the Surefire WarComp:


I have been eyeing Griffin Armament's FlashComp, as it seems like it would help rapid follow-ups, while not having all of the concussion/blast of a brake :





Very nice changes.

I, too, really like the flat face Geissele triggers. I have one on my AR-10A. Still using conventional trigger bows on the AR-15s. Maybe will change them out, but they work just fine the way they are.

Tying into my point above, does the KAC MAMS take as much blast away from the can as a traditional muzzle brake? It kind of looks like a compensator, with numerous small holes, rather than a barge blast chamber/baffle.

Last question, both your previous can and this one, are nice and compact. Given that this is an 11.5" 5.56, does the small can (and its limited volume) bring it down to hearing safe levels?

Flash hiders do not have any extra baffles the bullet passes through after it leaves the barrel. Comps with a closed end/cap if you will, are considered a sacrificial baffle before the first suppressor baffle. The Surefire, AAC, etc etc brakes have a lot of material to take the beating of the blast and direct it out the sides. With time, they do enlarge and wear the metal down. Especially on 10.x and shorter SBRs. Flash hiders do not take any of the blast and direct it elsewhere. The suppressor baffle takes the punishment then.

The KAC MAMS is unique in that all the ports/holes are angled differently. Those side ports do not act as a baffle. The end cap is whats protecting the suppressor baffle from the blast. The MAMS (multi axis muzzle stability) device is really a comp/brake. You achieve a lot of the results as a brake would, without the crazy flash, concussion, etc. Does it work as well as a straight up muzzle brake in reducing recoil, muzzle movement, NO, but it does a pretty good job at it, and excels in other categories the brake lacks. There are lots of threads on the topic with a lot more info then what I can post here. BradfordT had a great thread on the MAMS and other comps such as the EFAB.

I shoot both my SOCOM Mini and KAC CQB outside with no ears. Not saying it is the best for you, but I do it hunting small game regularly. It is still fairly loud and do not advocate for it unless your only shooting a round or two. Indoors, your ears still ring. Even with a RC on there or M4-2000, etc, etc.. still ring the ears and its loud. Not very pleasant.

[PatrioticDisorder]

Awesome write up, I myself have a similar set up, I'll be moving to the E-carrier as well. I was happy to hear about the flash difference between the KAC CQB & Surefire mini, however that's a lot of $$$ to achieve slightly less flash (KAC vs. Surefire) but the KAC sure is sexy looking. In defense of the Surefire, I'd imagine once the Wardens become available it will be less annoying to shoot unsuppressed than a MAMs...

[Jwknutson17]

Awesome write up, I myself have a similar set up, I'll be moving to the E-carrier as well. I was happy to hear about the flash difference between the KAC CQB & Surefire mini, however that's a lot of $$$ to achieve slightly less flash (KAC vs. Surefire) but the KAC sure is sexy looking. In defense of the Surefire, I'd imagine once the Wardens become available it will be less annoying to shoot unsuppressed than a MAMs...

Thanks. I would have never switched if I didn't already have the MAMS and the suppressor. This SBR is about the weight of my SPR with scope and bi-pod, light, etc etc. Not that it was the deciding factor in my choice to switch. The 4oz helps a little. But by no way I would buy a QDC CQB for just the weight or even the very small difference in flash. That is a null point in the grand scheme of things. Over all, I still like the surefire SOCOM cans the best. At least right now, today, at this moment While I have very little "sparks" on the mini on my 11.5 with Mk262s and 5.56 m193s, etc, It is a very very suttle difference between them. I do like the SOCOM mounting system the best hands down. Shooting without a can, the MAMS takes it and the main reason I switched. POI, Blowback, and noise sound the same on both the KAC and SOCOM Mini to me the shooter. Its a toss up. Like them both. Keeping both. Yes, the warden is interesting and worth considering for sure!