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KAK frt bcg (Page 1 of 2)
Posted: 6/4/2026 9:22:11 PM EDT
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Looks like Kak dropped a new bcg with a sliding weight built into the carrier. No need for an H2/3 buffer. KAK bcg |
Stolen Firearm: Colt AR15, Serial # SP342380, 16" carbine. Stolen in California by Kevin Ayres, and taken to Missouri.
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Originally Posted By Thefryzone: To bad their chromed sandcutter bolt carrier with down vents felt like a zipper and sounded like one to when I put it in my rifle. Sent it back and I'll never buy anything from them again.  Was the machining rough on the rails with sand cuts? |
Just watched a video on this. Looks good.  The KAK DBC. Is this the end of FRT tuning as we know it? I was about to order some more H3 buffers yesterday after swapping one of mine into a buddy's AR with a Partisan. |
| Looks like a clever alternative that would have been easy for KAK to make by adapting their 9mm tungsten bolt weight design but I wonder how the roll pin will hold up with the weight hammering it in both directions with each shot. Fortunately, the impact on closing with a rotating bolt is gentler than with a straight blowback bolt. Worst case, the roll pin could be reinforced with music wire or replaced with a solid pin. |
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I have an old Bushmaster M4 that is up next for an FRT but for some reason it came with a semi auto carrier. Ordered one of these for it since i needed a carrier and a buffer. Going to install a Disruptor in it today for when this carrier arrives later this week. Plan on testing it out in the next couple weeks. |
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Originally Posted By Thefryzone: To bad their chromed sandcutter bolt carrier with down vents felt like a zipper and sounded like one to when I put it in my rifle. Sent it back and I'll never buy anything from them again. "felt like a zipper and sounded like one" Can you explain this further? What do you mean? I've never hear that in reference to anything gun related. |
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I received my DBC carrier yesterday. The bore of the carrier is definitely on the small side, I tried a couple of different bolts and none pushed fully into the carrier with normal hand pressure, even with generous lube. I did manage to get one of the bolts to fit but it needed to be tapped home with a nylon hammer. The BCG does seem to hand cycle OK so hopefully it will function correctly and fit will loosen up over time. I plan to test it today in a troublesome 7.5” 5.56 SBR. I will report back. |
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Originally Posted By StealthyBlagga: I received my DBC carrier yesterday. The bore of the carrier is definitely on the small side, I tried a couple of different bolts and none pushed fully into the carrier with normal hand pressure, even with generous lube. I did manage to get one of the bolts to fit but it needed to be tapped home with a nylon hammer. The BCG does seem to hand cycle OK so hopefully it will function correctly and fit will loosen up over time. I plan to test it today in a troublesome 7.5” 5.56 SBR. I will report back. USPS has managed to lose mine apparently. Made it to Memphis then- Instead of Nashville it’s off in the ether near Minneapolis. Fuck I hate them. |
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Originally Posted By HKH: USPS has managed to lose mine apparently. Made it to Memphis then- Instead of Nashville it’s off in the ether near Minneapolis. Fuck I hate them. Probably just gonna send it on a nice trip somewhere before it finally arrives… |
a loaded gun won’t set you free, so you say…
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Originally Posted By bkpkr: Neat. Seems like a decent option for stocks with proprietary buffers. May end up trying one in my 8” 300blk with a Q shorty stock. Hey mang I’ve been able to get most of the 300s to run with anywhere from a a 3.4 to 4.1 weight ccb buffer AND an adjustable gas block. I’ve found gas mgt is key on a 300 with these stocks. The one pictured is hilariously slow but reliable. It’s like pow….pow….pow…pow   That is the B cubed Blue, bootleg Badger  (built out of a poverty pony)
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Tried mine out today in a Bushmaster M4 with a carbine buffer and disruptor. Couple fail to fires but potentially bad magazines still figuring it out. But otherwise it cycled fine, albeit noticeably slower than the other gun I brought. I was also shooting a Colt 604 upper on a spikes lower with a rifle length buffer. That fired substantially faster, also a couple ftf’s but whatever. For some reason this bushmaster came with a semi auto carrier so I needed a carrier and a buffer, so I went with this. Maybe it’ll run faster with a shorter barrel or suppressed. I ended up with like ten tromix buffers so now I need to order more FRT’s. |
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I was just gonna ask about this and here it is on AR15.com.... Oh, and why are H3 buffers like 70$, and a normal carbine H1 is $5? Seems like robbery. Can you take weights out of H1's and make one H3? I now have a graveyard of H1's.  I'm ordering one of these DB carriers now. |
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Originally Posted By AK74-U: Can you take weights out of H1's and make one H3? I now have a graveyard of H1's. I'm ordering one of these DB carriers now. Yes you can. Before tungsten prices got out of control, I was buying tungsten weights from KAK and rolling my own. |
We have to protect our phoney baloney jobs here, gentlemen! We must do something about this immediately! Immediately! Immediately! Harrumph! Harrumph! Harrumph!
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Originally Posted By AK74-U: I was just gonna ask about this and here it is on AR15.com.... Oh, and why are H3 buffers like 70$, and a normal carbine H1 is $5? Seems like robbery. Can you take weights out of H1's and make one H3? I now have a graveyard of H1's. I'm ordering one of these DB carriers now. You certainly can, if you're finding H1s for 5 bucks. Remember, an H1 has 1 tungsten, and 2 steel weights. The typical buffer in most commercial ARs is just a standard carbine, with 0 tungsten and 3 steel weights. It really is as simple as an extreme tungsten shortage at the moment. There's no gouging, or ripping you off. Tungsten is insanely expensive. |
It was not preached to the crowd,
It was not taught by the State.
No man spoke it aloud,
When the English began to hate.
It was not taught by the State.
No man spoke it aloud,
When the English began to hate.
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Originally Posted By ELittlefield: You certainly can, if you're finding H1s for 5 bucks. Remember, an H1 has 1 tungsten, and 2 steel weights. The typical buffer in most commercial ARs is just a standard carbine, with 0 tungsten and 3 steel weights. It really is as simple as an extreme tungsten shortage at the moment. There's no gouging, or ripping you off. Tungsten is insanely expensive. I mis-spoke, I have like 8 idle buffers, with 1 tungsten weight combined for all. All these are just standard CAR buffers with 1 H1. Looks like I need Tungsten weights.  What's the best deal going for H3's (where?) |
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Originally Posted By AK74-U: What's the best deal going for H3's (where?) Tromix is presently the best deal available for an H3 that will handle your rate of fire. @TonyRumore But, as this is the KAK BCG thread, I'd try the buffers I have. The KAK BCG is supposed to dead blow itself - if it works, you should be able to adjust rate of fire with buffer weight. |
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Originally Posted By StealthyBlagga: I received my DBC carrier yesterday. The bore of the carrier is definitely on the small side, I tried a couple of different bolts and none pushed fully into the carrier with normal hand pressure, even with generous lube. I did manage to get one of the bolts to fit but it needed to be tapped home with a nylon hammer. The BCG does seem to hand cycle OK so hopefully it will function correctly and fit will loosen up over time. I plan to test it today in a troublesome 7.5” 5.56 SBR. I will report back. Where you able to test this? |
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Originally Posted By AK74-U: I mis-spoke, I have like 8 idle buffers, with 1 tungsten weight combined for all. All these are just standard CAR buffers with 1 H1. Looks like I need Tungsten weights. What's the best deal going for H3's (where?) Originally Posted By AK74-U: Originally Posted By ELittlefield: You certainly can, if you're finding H1s for 5 bucks. Remember, an H1 has 1 tungsten, and 2 steel weights. The typical buffer in most commercial ARs is just a standard carbine, with 0 tungsten and 3 steel weights. It really is as simple as an extreme tungsten shortage at the moment. There's no gouging, or ripping you off. Tungsten is insanely expensive. I mis-spoke, I have like 8 idle buffers, with 1 tungsten weight combined for all. All these are just standard CAR buffers with 1 H1. Looks like I need Tungsten weights. What's the best deal going for H3's (where?) Tromix has the most affordable FRT buffers out there. It's a 2 piece buffer, with a large, heavy piece of steel acting as the dead blow mass to avoid expensive tungsten. I own about 8 of them now, I think. Tony is the real deal, and is an active member here on this site. He's been innovating parts for AR15s since I was in diapers. https://tromix.com/product/ar-15-h3-buffer-carbine/ |
It was not preached to the crowd,
It was not taught by the State.
No man spoke it aloud,
When the English began to hate.
It was not taught by the State.
No man spoke it aloud,
When the English began to hate.
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Originally Posted By country_boy87: Were you able to test this? Yes. Didn’t work with any of the buffers I tried - standard to H3. I’m not sure if it’s the tightness of the bolt fit or the way the dead blow weight works. This 7.5” rifle worked OK with a regular semi-auto trigger and Colt-style 9mm buffer, but has proved more stubborn with a TTC Disruptor. I’m going to try the DBC in a known-reliable rifle with a different FRT next. |
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Originally Posted By StealthyBlagga: Yes. Didn’t work with any of the buffers I tried - standard to H3. I’m not sure if it’s the tightness of the bolt fit or the way the dead blow weight works. This 7.5” rifle worked OK with a regular semi-auto trigger and Colt-style 9mm buffer, but has proved more stubborn with a TTC Disruptor. I’m going to try the DBC in a known-reliable rifle with a different FRT next. What? It didn’t work? Damn. Really hoping this was the solution for the CQB buffer system that I have a lot of. Until Tony comes out with a cqb dead blow buffer Right @tonyrumore Hello don’t even know if the physics are possible I figured I’d just ask our mad Genius gun wizard. |
2A cops on YT just dropped another video with the kak db bcg -this time testing it with different buffers and springs to see what affect they would have.  KAK DBC Followup: But What If I Use (fill in blank)? |
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Originally Posted By StealthyBlagga: Yes. Didn’t work with any of the buffers I tried - standard to H3. I’m not sure if it’s the tightness of the bolt fit or the way the dead blow weight works. This 7.5” rifle worked OK with a regular semi-auto trigger and Colt-style 9mm buffer, but has proved more stubborn with a TTC Disruptor. I’m going to try the DBC in a known-reliable rifle with a different FRT next. I was going to buy the carrier for my m4a1 clone, but im not liking what youre saying about bolt fitment. |
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Originally Posted By country_boy87: I was going to buy the carrier for my m4a1 clone, but im not liking what youre saying about bolt fitment. My thoughts as well. Seems like the way to go is a complete KAK BCG assy. I would probably buy the down vented one. I picked up another $75 H3 buffer locally instead. |
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Originally Posted By ELittlefield: Tromix has the most affordable FRT buffers out there. It's a 2 piece buffer, with a large, heavy piece of steel acting as the dead blow mass to avoid expensive tungsten. I own about 8 of them now, I think. Tony is the real deal, and is an active member here on this site. He's been innovating parts for AR15s since I was in diapers. https://tromix.com/product/ar-15-h3-buffer-carbine/ $39!!! I should've bought 2 of those instead of the $75 H3 buffer... |
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I wasn't having a lot of luck with FRT tuning in my ARs, this after getting an Atrius working in an AR22 upper on my 80% lower and modding my HK SP89 (kinda sorta MP5K) with a Super Safety. Running 80% lowers, one with an Atrius and another with a Partisan Disruptor both under Midway Stoner M4 223 uppers (don't shoot me). Tried H3 buffer in both with no luck and seeing light primer strikes with the hammer down on opening the action so either bolt bounce or hammer follow. I put the KAK DBC BCG in and things worked immediately with both lowers. Not really happy having to drop another $250 to get the FRTs to work and so I'm trying different Sprinco springs and mixing in H3 and H2 buffers (so 6 or 8 combos?). I like the KAK BCG with the down vent, dual ejectors, chrome bolt and other features, I'm just a cheap bastard and want to make it work as others have with buffer and spring changes. |
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Originally Posted By Steamedliver: Hope they eventually make it in 9mm (or are able to make it for 9mm). I’ve not pulled the reciprocating bolt weight from mine to compare it with a 9mm bolt weight, but I have to believe it is lighter. This means a heavier buffer would probably still be needed to achieve minimum safe overall mass in a blowback system. I suppose they could make the reciprocating weight from tungsten (like their aftermarket 9mm bolt weight) but that would defeat the purpose (low cost of a steel weight). |
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Originally Posted By Steamedliver: Down vent or side vent? Originally Posted By boomfab: Down. And running the Rare Breed 3 position FRT. Yea. Quoted myself after doing some reading. Can you tell me the pros and cons of each. Or point me in the right direction to read on it? |
Words fall from your mouth like shit from ass.
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Originally Posted By ELittlefield: Tromix has the most affordable FRT buffers out there. It's a 2 piece buffer, with a large, heavy piece of steel acting as the dead blow mass to avoid expensive tungsten. I own about 8 of them now, I think. Tony is the real deal, and is an active member here on this site. He's been innovating parts for AR15s since I was in diapers. https://tromix.com/product/ar-15-h3-buffer-carbine/ A Tromix buffer in a 16" AR-9 with Super Selector ran quite reliably. Fast ROF. FAST. Maybe 1000 rounds per minute by my ear. I owned a Sten and MAC-10 .45. Yes, I fully understand FAST |
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Originally Posted By eddiebunkaz: A Tromix buffer in a 16" AR-9 with Super Selector ran quite reliably. Fast ROF. FAST. Maybe 1000 rounds per minute by my ear. I owned a Sten and MAC-10 .45. Yes, I fully understand FAST Which T buffer did you use, the standard h3, the 9mm extended, or other? |
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Ordered just the carrier today for my 300 blackout pistol. Sorry for dumb questions here: it's been maybe 10 years or more since Ive built this, from a PSA pistol kit and I want to say it's got some special buffer in it. Like a pistol buffer is what's in my mind, but I know there's not something called that. Will I have to change that to a carbine buffer now? |
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I finally got back around to retesting the KAK DBC in my 7.5” 5.56. I determined that what I thought was bolt bounce was actually a problem with the Triggered Disruptor I put in this gun. Switching to a Rare Breed FRT-15L3 got it running reliably in FRT mode. Full disclosure: My use case is unusual - I am using the DBC with a Tromix H4 buffer to slow down the insane bolt velocity that was outrunning my PMAGs. Rate of fire seems much more usable now. |
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Originally Posted By country_boy87: Ordered just the carrier today for my 300 blackout pistol. Sorry for dumb questions here: it's been maybe 10 years or more since Ive built this, from a PSA pistol kit and I want to say it's got some special buffer in it. Like a pistol buffer is what's in my mind, but I know there's not something called that. Will I have to change that to a carbine buffer now? I would try it as is. If you watch the latest PSR video, he tests the DBC on several different guns including honey badger clone with a pistol brace and shorty buffer and it was working. Skip to 13:55 to see.  Big Tungsten Hates This BCG |
KAK frt bcg (Page 1 of 2)
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