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Originally Posted By MikeWhiskey: Good deal! PCCs are definitely not as straightforward as 5.56/.300 Blackout builds... No worries!  Originally Posted By MikeWhiskey: Originally Posted By ELittlefield: I will be building a 9mm retro AR, mostly of PSA parts. I have a second Rare Breed FRT on the way, in addition to a Kaw Valley 10 ounce buffer and an XP spring. I will let y'all know how it goes. Good deal! PCCs are definitely not as straightforward as 5.56/.300 Blackout builds... Originally Posted By mini14jac: Sorry. Reading is fundamental. No worries! I am HIGHLY motivated to make this work. A 9mm blaster would be boner medicine. |
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Originally Posted By hrt4me: Spikes Tactical lower receiver DTT FRT-15L3 A5 receiver extension, KynShot RB-5007 9mm hydraulic buffer, Tubb flatware recoil spring Ares Shrike upper receiver How is the Hydraulic buffer with the FRT? I've been considering snagging one of the Carbine Kynshot for mine to see how it effects shot dispersion and rof. |
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Originally Posted By ELittlefield: I am HIGHLY motivated to make this work. A 9mm blaster would be boner medicine. Yes it would! Try subsonic ammo with a suppressor...and you just might have to go the emergency room after 4 hours! First thread I ever started that made it page 2! Not surprising with the number of responses that are mine however... 
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I previously mentioned that I REALLY wasn't a fan of the safety/selector that comes with the DTT/RBT FRTs. I apologize; in hindsight that was a grotesque UNDERstatement. After installing @ssgtcarroll custom machined MIL spec safety/selector, I'm confident in saying that the ones that come with the FRTs are complete dag shite, and the ones that @ssgtcarroll are making are THE standard; at least for me. They're NOT ambi however, and I thought he mentioned he might be looking at doing that down the road but I don't wanna put words in his mouth. In the picture below you can actually see space from the DTT/RBT safety/selector on an Aero Precision lower: Attached File @ssgtcarroll's fit exactly as you would expect a MIL spec safety/selector to fit in a MIL spec receiver; perfectly! Attached File Attached File Where the stock safety/selector felt janky/mushy and otherwise imprecise; this feels the polar opposite and what you would expect. The stock piece was my biggest gripe with the FRT and for short money it's fixed. While swapping the one out on my CMMG Banshee I noticed some a couple things that were NOT giving me a warm fuzzy. This particular PCC had the highest round count out of all the FRT installs I've been testing, but wasn't higher than 300. Both sides/selectors had worked loose from their Torx head retaining screw, which came pre-gooped with LocTite. I had torqued them as far as I felt comfortable with when installing it previously, and this was NOT an issue on any of the other installs, just making note. Another thing I noticed is that the detent itself was definitely showing signs of wear and you can see tiny metal shavings on the mat around the tip of the detent, which is showing silver from the damage while the rest of it is more brass colored. (sorry that the picture is slightly out of focus.) I'd attribute this to the sloppiness in the stock safety/selector and additional, out of spec movement causing the galling of the detent. That's a layman's opinion as I'm not a machinist or metallurgist and there's way more knowledgeable people here that might know what's up; just my observation. Attached File |
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Yes, anti-walk pins are required - standard GI pins will fall out. If the authentic MilSpec look is important to you, the appearance of the trigger itself will be more concerning. Edited to clarify I meant GI push-in pins as opposed to the anti-walk lins that come with the RB trigger |
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Originally Posted By hrt4me: @MikeWhiskey, does the RB/DTT FRT-15L3 require anti-walk pins? or would mil-spex hammer & trigger pins work without falling out of the lower receiver? It's a cassette style trigger that comes with it's own set of pins/Torx screws:  Admittedly they're sloppy, and on every install I've done there's slight side to side play that would be alleviated by the addition of anti-walk pins (like KNS, which I've used previously and like) and is another modification/upgrade (like @ssgtcarroll's safety/selector) that I think is mandatory for serious (as opposed to "range toy") use. Great question, thanks for asking! |
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Originally Posted By StealthyBlagga: Yes, anti-walk pins are required - standard pins will fall out. If the authentic MilSpec look is important to you, the appearance of the trigger itself will be more concerning. I wouldn't say they're going to fall out; the Torx screws on both sides of the threaded trigger pins are larger than the diameter of the hammer/trigger pin holes...but the pins themselves are definitely longer than they need to be which is why there's side to side play. I'm not sure if the how the trigger is fitted into the cassette and if it's interchangeable with anything else for those folks that are concerned with the look/appearance of the trigger itself...and I'm not brave enough to start tearing into a $500 trigger either! I found the janky safety/selector to be a bigger concerned, primarily function but also appearance wise, but @ssgtcarroll has that covered for short money... |
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Installed RB/DTT FRT-15L3 in a Sig MPX K with Midnight Machine trip bar. Ran 100% suppressed with form 1 can using factory subsonics from Remington and S&B. Extremely easy to control with short bursts. Only one range trip with ~130 rounds on the system, but no malfunctions yet. Downsides: The MM trip bar requires extensive fitting to work. This has also been indicated by at least two YT reviewers as well. One of the slotted holes was binding on the forward roll pin and the trip bar tail was binding on the underside of the bolt carrier. Luckily I had the tools and patience to correct these shortcomings but YMMV. There are other trip bar mfg’s out there with other users reporting better results. The MM trip bar should be considered a “kit” and not a finished product IMHO. It’s anything but drop in, at least for some. Like OP, I found the factory ambi safety to be sloppy and not confidence inspiring. It worked but I’ll be looking for a replacement eventually. |
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Sig MPX 4.5" - Added a sear trip bar to the upper. No issues. Sig Virtus 5.56 11.5" - Added a sear trip bar to the upper. The FRT did not work with the default firing pin latch or with a G-marked firing pin latch. In normal semi-auto mode, sometimes the round wouldn't go off when the hammer dropped. In FRT mode, sometimes it would do a 2-3 round burst, but mostly failures to fire like normal semi-auto. However, once the firing pin latch was totally removed, there were no issues at all in either mode. Fightlite MCR - No issues with the FRT that I can tell. My MCR works fine when fed from a magazine, but occasionally has failures to feed when fed from a belt. However it appears to be a problem with the MCR since I don't have that many rounds through it yet and it's probably not completely broken in. |
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Originally Posted By CleverNickname: Sig MPX 4.5" - Added a sear trip bar to the upper. No issues. Sig Virtus 5.56 11.5" - Added a sear trip bar to the upper. The FRT did not work with the default firing pin latch or with a G-marked firing pin latch. In normal semi-auto mode, sometimes the round wouldn't go off when the hammer dropped. In FRT mode, sometimes it would do a 2-3 round burst, but mostly failures to fire like normal semi-auto. However, once the firing pin latch was totally removed, there were no issues at all in either mode. Fightlite MCR - No issues with the FRT that I can tell. My MCR works fine when fed from a magazine, but occasionally has failures to feed when fed from a belt. However it appears to be a problem with the MCR since I don't have that many rounds through it yet and it's probably not completely broken in. It would be interesting to know if it would work with the firing pin latch on the Spear LT BCG, or whether it would also have to be removed. It comes in from the side vs the top. I've also been curious whether it would work with the Spear LT 7.62x39 which supposedly needs a heavier hammer spring than mil-spec triggers. |
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Originally Posted By deltaheavy: Installed RB/DTT FRT-15L3 in a Sig MPX K with Midnight Machine trip bar. Ran 100% suppressed with form 1 can using factory subsonics from Remington and S&B. Extremely easy to control with short bursts. Only one range trip with ~130 rounds on the system, but no malfunctions yet. Downsides: The MM trip bar requires extensive fitting to work. This has also been indicated by at least two YT reviewers as well. One of the slotted holes was binding on the forward roll pin and the trip bar tail was binding on the underside of the bolt carrier. Luckily I had the tools and patience to correct these shortcomings but YMMV. There are other trip bar mfg’s out there with other users reporting better results. The MM trip bar should be considered a “kit” and not a finished product IMHO. It’s anything but drop in, at least for some. Like OP, I found the factory ambi safety to be sloppy and not confidence inspiring. It worked but I’ll be looking for a replacement eventually. Thanks for posting your results, especially in a other than standard AR platform, there's no shortage of Sig folks who want to see this figured out and it's appreciated! Originally Posted By CleverNickname: Sig MPX 4.5" - Added a sear trip bar to the upper. No issues. Sig Virtus 5.56 11.5" - Added a sear trip bar to the upper. The FRT did not work with the default firing pin latch or with a G-marked firing pin latch. In normal semi-auto mode, sometimes the round wouldn't go off when the hammer dropped. In FRT mode, sometimes it would do a 2-3 round burst, but mostly failures to fire like normal semi-auto. However, once the firing pin latch was totally removed, there were no issues at all in either mode. Fightlite MCR - No issues with the FRT that I can tell. My MCR works fine when fed from a magazine, but occasionally has failures to feed when fed from a belt. However it appears to be a problem with the MCR since I don't have that many rounds through it yet and it's probably not completely broken in. More excellent Sig platform related information, thanks! Originally Posted By jwlaxton: It would be interesting to know if it would work with the firing pin latch on the Spear LT BCG, or whether it would also have to be removed. It comes in from the side vs the top. I've also been curious whether it would work with the Spear LT 7.62x39 which supposedly needs a heavier hammer spring than mil-spec triggers. Agreed, especially curious about the x39 application myself. Post match today I test fired 3 installs of @ssgtcarroll's machined MIL safety/selector. While I previously dry fired it post installation and it acted exactly as the stock/ambi safety/selector did I wanted to get some live fire. Another gentlemen with a Sig with a Parker Mountain Machine trip bar (5.56) was there and had the DTT/RBT stock safety/selector installed on his. All 3 installs of @ssgtcarroll's safeties worked perfectly; CMMG Banshee .45 PCC/SBR, 300 Blackout suppressed/subsonic Aero Precision build and 5.56 SBR/OSS K-can Aero build as mentioned in OP. Several people did finger bang both the stock and Mike's safety and the consensus was it was NO comparison; the stock has a janky, vague, sloppy and toy like feel while his is a legit MIL spec duty use piece. I get how so people might be chapped about having to spend another $40+ on another safety and likewise for KNS Precision anti-rotation trigger/hammer pins when you're already $500 into the FRT itself but that's relatively short money to get it over the finish line and going from range toy to serious/duty use... |
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Originally Posted By hrt4me: Spikes Tactical lower receiver DTT FRT-15L3 A5 receiver extension, KynShot RB-5007 9mm hydraulic buffer, T  ubb flatware recoil springAres Shrike upper receiver What is recoil and rate of fire like with this combo? Does it have any issues with that flat wire spring stripping rounds from new links? |
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Took out the franken-9mm today to test. My other 9mm SBR is a matador upper with a folding stock, so not appropriate to test. Test subject today was a $200 used 9mm upper of unknown provenance and a Spikes 9mm dedicated lower. I've never had a Spike's product in spec. 10 oz buffer. Couldn't get it to run. Trigger would not reset. If I pull back the handle, I have to release the trigger ever so slightly to hear the click. Upon examination and much tinkering, it appears this bolt is not pushing the hammer down far enough to force the reset. I added some tape to the bottom of the carrier to make it "thicker" and was able to make it reset. I need a new 9mm bolt to further test, and my fun-funds are decimated at the moment. |
"Here we are having a nice discussion on swords and the fucking pikemen gotta shit all over the place." - Silverbulletz06
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Originally Posted By BUCC_Guy: Took out the franken-9mm today to test. My other 9mm SBR is a matador upper with a folding stock, so not appropriate to test. Test subject today was a $200 used 9mm upper of unknown provenance and a Spikes 9mm dedicated lower. I've never had a Spike's product in spec. 10 oz buffer. Couldn't get it to run. Trigger would not reset. If I pull back the handle, I have to release the trigger ever so slightly to hear the click. Upon examination and much tinkering, it appears this bolt is not pushing the hammer down far enough to force the reset. I added some tape to the bottom of the carrier to make it "thicker" and was able to make it reset. I need a new 9mm bolt to further test, and my fun-funds are decimated at the moment. This is how my Colt was. I took the trigger back apart and stoned where the trip lever contacts the disconnecter. Not enough to remove a ton of material but to just clean up contact areas. You don’t need to remove the trip lever from the pack. Just the hammer and trigger. The trip lever is a pain to get back in. |
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Originally Posted By BUCC_Guy: Took out the franken-9mm today to test. My other 9mm SBR is a matador upper with a folding stock, so not appropriate to test. Test subject today was a $200 used 9mm upper of unknown provenance and a Spikes 9mm dedicated lower. I've never had a Spike's product in spec. 10 oz buffer. Couldn't get it to run. Trigger would not reset. If I pull back the handle, I have to release the trigger ever so slightly to hear the click. Upon examination and much tinkering, it appears this bolt is not pushing the hammer down far enough to force the reset. I added some tape to the bottom of the carrier to make it "thicker" and was able to make it reset. I need a new 9mm bolt to further test, and my fun-funds are decimated at the moment. Before you start modifying your expensive trigger or buy a new bolt, see if the trigger dry functions as it should with your original bolt weight removed and a regular carbine-length buffer in place of the longer 10oz buffer. I had a similar problem with another type of FRT as described in this thread. The fix was to replace the factory bolt weight with a KAK extra heavy tungsten bolt weight and then use an H3 buffer. This combination eliminated premature trip activation by the bolt weight and got me to a safe reciprocating weight range while allowing the bolt to travel back far enough to fully reset my trigger. IMPORTANT: Do not shoot the gun without the bolt weight and a heavy buffer - this would not be a safe configuration. I hope my description makes sense. I can’t promise this will work in your case, but it costs nothing to try (assuming you already have a carbine buffer on hand). |
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Originally Posted By StealthyBlagga: Before you start modifying your expensive trigger or buy a new bolt, see if the trigger dry functions as it should with your original bolt weight removed and a regular carbine-length buffer in place of the longer 10oz buffer. I had a similar problem with another type of FRT as described in this thread. The fix was to replace the factory bolt weight with a KAK extra heavy tungsten bolt weight and then use an H3 buffer. This combination eliminated premature trip activation by the bolt weight and got me to a safe reciprocating weight range while allowing the bolt to travel back far enough to fully reset my trigger. IMPORTANT: Do not shoot the gun without the bolt weight and a heavy buffer - this would not be a safe configuration. I hope my description makes sense. I can't promise this will work in your case, but it costs nothing to try (assuming you already have a carbine buffer on hand). Originally Posted By StealthyBlagga: Originally Posted By BUCC_Guy: Took out the franken-9mm today to test. My other 9mm SBR is a matador upper with a folding stock, so not appropriate to test. Test subject today was a $200 used 9mm upper of unknown provenance and a Spikes 9mm dedicated lower. I've never had a Spike's product in spec. 10 oz buffer. Couldn't get it to run. Trigger would not reset. If I pull back the handle, I have to release the trigger ever so slightly to hear the click. Upon examination and much tinkering, it appears this bolt is not pushing the hammer down far enough to force the reset. I added some tape to the bottom of the carrier to make it "thicker" and was able to make it reset. I need a new 9mm bolt to further test, and my fun-funds are decimated at the moment. Before you start modifying your expensive trigger or buy a new bolt, see if the trigger dry functions as it should with your original bolt weight removed and a regular carbine-length buffer in place of the longer 10oz buffer. I had a similar problem with another type of FRT as described in this thread. The fix was to replace the factory bolt weight with a KAK extra heavy tungsten bolt weight and then use an H3 buffer. This combination eliminated premature trip activation by the bolt weight and got me to a safe reciprocating weight range while allowing the bolt to travel back far enough to fully reset my trigger. IMPORTANT: Do not shoot the gun without the bolt weight and a heavy buffer - this would not be a safe configuration. I hope my description makes sense. I can't promise this will work in your case, but it costs nothing to try (assuming you already have a carbine buffer on hand). I think we are very much on the same page as far as diagnosing. In lieu of swapping in a standard carbine buffer, I removed the rubber/nylon buffer head on the extended 10 oz to see if length of travel was the issue. The extra half-inch didn't make a difference, as I was really hoping taking a little material off that buffer would work. No such luck. Given the possible interference of the buffer weight in the bolt with the trip, I removed that also to no effect. After playing and thinking and tinkering, it dawned on me that the bolt just needs a c*nt hair more material on the bottom. |
"Here we are having a nice discussion on swords and the fucking pikemen gotta shit all over the place." - Silverbulletz06
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Originally Posted By BUCC_Guy: I think we are very much on the same page as far as diagnosing. In lieu of swapping in a standard carbine buffer, I removed the rubber/nylon buffer head on the extended 10 oz to see if length of travel was the issue. The extra half-inch didn't make a difference, as I was really hoping taking a little material off that buffer would work. No such luck. Given the possible interference of the buffer weight in the bolt with the trip, I removed that also to no effect. After playing and thinking and tinkering, it dawned on me that the bolt just needs a c*nt hair more material on the bottom. @BUCC_Guy Just to note again this is exactly what was wrong with my 635. How I fixed it is in the post above. If you need photos let me know. |
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I have installed the FRT FRT-15 L3 in a CMMG Banshee Mk47 (8”) pistol, chambered in 7.62x39 and it doesn't pass the function checks. I removed the upper, to test installation and it passed. So, I suspect the non-MILSPEC, PowerBolt (AR-10 size) is the culprit but, it was worth the attempt. |
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Originally Posted By ASKJesse: I have installed the FRT FRT-15 L3 in a CMMG Banshee Mk47 (8”) pistol, chambered in 7.62x39 and it doesn't pass the function checks. I removed the upper, to test installation and it passed. So, I suspect the non-MILSPEC, PowerBolt (AR-10 size) is the culprit but, it was worth the attempt. Thanks for posting and unfortunately that seems to be the case. When Micah (ex-Flannel Daddy/Garand Thumb dude) did his FRT YouTube video and got the Q .308 to work he made a comment that he uses a lightweight/5.56 sized BCG (IIRC) which was likely why it worked. He seemed to think it would be a VERY minor fix/adjustment/part swap to get them to work properly in AR-10 sized platforms. Obviously the market isn't nearly as big, but it'd be nice if they did... |
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Originally Posted By MikeWhiskey: Thanks for posting and unfortunately that seems to be the case. When Micah (ex-Flannel Daddy/Garand Thumb dude) did his FRT YouTube video and got the Q .308 to work he made a comment that he uses a lightweight/5.56 sized BCG (IIRC) which was likely why it worked. He seemed to think it would be a VERY minor fix/adjustment/part swap to get them to work properly in AR-10 sized platforms. Obviously the market isn't nearly as big, but it'd be nice if they did... Cough |
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Originally Posted By ssgtcarroll: @BUCC_Guy Just to note again this is exactly what was wrong with my 635. How I fixed it is in the post above. If you need photos let me know. Originally Posted By ssgtcarroll: Originally Posted By BUCC_Guy: I think we are very much on the same page as far as diagnosing. In lieu of swapping in a standard carbine buffer, I removed the rubber/nylon buffer head on the extended 10 oz to see if length of travel was the issue. The extra half-inch didn't make a difference, as I was really hoping taking a little material off that buffer would work. No such luck. Given the possible interference of the buffer weight in the bolt with the trip, I removed that also to no effect. After playing and thinking and tinkering, it dawned on me that the bolt just needs a c*nt hair more material on the bottom. @BUCC_Guy Just to note again this is exactly what was wrong with my 635. How I fixed it is in the post above. If you need photos let me know. I'm going to look into this, I've just been slammed with meetings and lawyers and contract nonsense for days. I was hesitant to take any material, but I suppose a hair off and having the disconnector engage easier doesn't have any negative second order effects, unless one were to go HAM and take off so much that it can't engage at all. Havent had a chance to take it apart to see if I'm even following that correctly. Maybe later after my next meeting. Work from home day FTW. |
"Here we are having a nice discussion on swords and the fucking pikemen gotta shit all over the place." - Silverbulletz06
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One thing I’m curious about hearing from others is whether or not they experienced an increase in the rate of fire as the magazine emptied…? All of my most recent FA experience has been with burst mechanisms, and belt feds are a different animal. While I was doing my most recent test fire I asked the gentleman with me what he thought and in the interest of starting with a clean slate, loaded a 28-round magazine to do a complete mag dump and sure enough as the magazine emptied the ROF increased without question. I’m not sure that would be any different in an AR with a DIAS and I’m not looking to accelerate any parts breakage either, just something I noticed…🧐 I’m also experienced some bolt bounce in my 5.56 AR that has an H2 buffer and was curious about buffer options besides an H3, I’ve seen some folks using other than those 2 options to get a handle on bolt speed/bounce. |
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Originally Posted By ssgtcarroll: I’ve noticed a slow down as they get hot. Also wondering if you are pulling harder on the trigger. Interdasting (as my daughter says...) and quite possible, I'll have to take note of it the next time I let one rip... I REALLY don't want to make a habit of that for obvious reasons, unless, well, science! |
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CMMG Banshee FE MkGs 9mm Bolt Tuning Weights and buffers with a 5" barrel. Went back to the range today and did a little more testing. I was hoping to get full function at a good semi ROF with both suppressed subsonic, and supers with no suppressor. All of this was tested with a standard carbine spring. Subs were AAC 147gr FMJ and Supers were TulAmmo 115gr FMJ. Here's what I measured with a scale: The CMMG bolt tuning weights, which come in a kit of 3, each weigh 1oz, 2oz, and 3.3oz. They also come with a roll pin and some spares that are a negligible weight difference. The stock CMMG carbine buffer weighs 3oz. My H2 buffer weighs 4.6oz. I get a dead trigger in the third position when shooting suppressed with 147gr subsonic ammo using the factory 3oz carbine buffer and any combination of bolt tuning weights from "none" all the way up to the 3.3oz weight. It just doesn't like to run this way. I think making the bolt heavier doesn't mitigate bounce at all, it only slows ROF and decreases bolt travel. Swapping in the H2 buffer made it run reliably and lock back on empty mags using 147gr subs. But it was slooooow with the 3.3oz and the 2oz bolt tuning weights. Removing the bolt tuning weights and keeping the H2 buffer allowed for reliable suppressed running and locking back on empty mags with the 147gr subs. Max achievable semi ROF appears to be 600 RPM as I measured a .10 split time with my shot timer. I'd like it a little faster, but I didn't have an H1 buffer to try. I think this is a reasonable compromise and it's probably more controllable anyway. You can easily do doubles and triples. Unfortunately, it just doesn't quite want to lock back on empties using 115gr FMJ supers and no suppressor. It will cycle and run in semi, but the H2 buffer without a suppressor adding back pressure is just not enough to clear the bolt catch. So, the addition of 1.6oz of reciprocal weight using an H2 buffer worked, but 2oz of fixed weight in the bolt with the standard buffer did not work for fixing the dead trigger issue with suppressed subs. It may be that an H1 is the sweet spot that lets it run a variety of subs and supers, with and without a suppressor, lock back on empty mags, and have a not-too-slow cycle. I'm going to get an H1 and try it in the future. For now it seems the best option is just to swap buffers between standard and H2 depending if you are running suppressed subs or unsuppressed supers. I hope the H1 is the magic cure-all but will have to wait to find out. Someone with more experience might chime in and and confirm that heavier bolts bounce more than lighter ones. It seems like you want as much of the weight to be reciprocating "dead blow" weight as possible, so maybe skip the bolt tuning weight kit unless you'll only ever shoot semi semi, and use an assortment of standard, H1 and H2 buffers to find the sweet spot for your gun. |
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https://imgur.com/a/3ckxNt7 Rare Breed trigger, with ssgtcarroll's selector, H2 buffer, and... 458 SOCOM. 12" barrel with Hybrid 46.
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Originally Posted By ELittlefield: https://imgur.com/a/3ckxNt7 Rare Breed trigger, with ssgtcarroll's selector, H2 buffer, and... 458 SOCOM. 12" barrel with Hybrid 46. Bad ass. |
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Originally Posted By Jambalaya: CMMG Banshee FE MkGs 9mm Bolt Tuning Weights and buffers with a 5" barrel. Went back to the range today and did a little more testing. I was hoping to get full function at a good semi ROF with both suppressed subsonic, and supers with no suppressor. All of this was tested with a standard carbine spring. Subs were AAC 147gr FMJ and Supers were TulAmmo 115gr FMJ. Here's what I measured with a scale: The CMMG bolt tuning weights, which come in a kit of 3, each weigh 1oz, 2oz, and 3.3oz. They also come with a roll pin and some spares that are a negligible weight difference. The stock CMMG carbine buffer weighs 3oz. My H2 buffer weighs 4.6oz. I get a dead trigger in the third position when shooting suppressed with 147gr subsonic ammo using the factory 3oz carbine buffer and any combination of bolt tuning weights from "none" all the way up to the 3.3oz weight. It just doesn't like to run this way. I think making the bolt heavier doesn't mitigate bounce at all, it only slows ROF and decreases bolt travel. Swapping in the H2 buffer made it run reliably and lock back on empty mags using 147gr subs. But it was slooooow with the 3.3oz and the 2oz bolt tuning weights. Removing the bolt tuning weights and keeping the H2 buffer allowed for reliable suppressed running and locking back on empty mags with the 147gr subs. Max achievable semi ROF appears to be 600 RPM as I measured a .10 split time with my shot timer. I'd like it a little faster, but I didn't have an H1 buffer to try. I think this is a reasonable compromise and it's probably more controllable anyway. You can easily do doubles and triples. Unfortunately, it just doesn't quite want to lock back on empties using 115gr FMJ supers and no suppressor. It will cycle and run in semi, but the H2 buffer without a suppressor adding back pressure is just not enough to clear the bolt catch. So, the addition of 1.6oz of reciprocal weight using an H2 buffer worked, but 2oz of fixed weight in the bolt with the standard buffer did not work for fixing the dead trigger issue with suppressed subs. It may be that an H1 is the sweet spot that lets it run a variety of subs and supers, with and without a suppressor, lock back on empty mags, and have a not-too-slow cycle. I'm going to get an H1 and try it in the future. For now it seems the best option is just to swap buffers between standard and H2 depending if you are running suppressed subs or unsuppressed supers. I hope the H1 is the magic cure-all but will have to wait to find out. Someone with more experience might chime in and and confirm that heavier bolts bounce more than lighter ones. It seems like you want as much of the weight to be reciprocating "dead blow" weight as possible, so maybe skip the bolt tuning weight kit unless you'll only ever shoot semi semi, and use an assortment of standard, H1 and H2 buffers to find the sweet spot for your gun. That is excellent and comprehensive information, thanks @Jambalaya, it's very much useful and appreciated. I said it before and I'll say it again as witnessed by this response; the RBTs definitely work with PCCs, they just require a lot more trial and error than the 5.56/.300 Blackouts do. In their defense, RBT only recommends their FRT for 5.56/.300 Blackout even though it works in other applications; it's just not as straight a line. A lot of folks are NOT interested in doing what it takes to make it work which is why I appreciate y'all making the effort and posting the results. Attached File |
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Originally Posted By MikeWhiskey: That is excellent and comprehensive information, thanks @Jambalaya, it's very much useful and appreciated. I said it before and I'll say it again as witnessed by this response; the RBTs definitely work with PCCs, they just require a lot more trial and error than the 5.56/.300 Blackouts do. In their defense, RBT only recommends their FRT for 5.56/.300 Blackout even though it works in other applications; it's just not as straight a line. A lot of folks are NOT interested in doing what it takes to make it work which is why I appreciate y'all making the effort and posting the results. /media/mediaFiles/sharedAlbum/toast_gif-994.gif Glad to help, hopefully it saves someone a little time and money being able to go right to the configuration that works for the ammo they want to use, and with/without suppressor. It's worth mentioning that a straight blowback gun runs much faster using the same barrel length, suppressor and ammo using an 11oz 9mm length KAK deadblow buffer. The RDB has a significant and noticeable effect on ROF. |
...believe in me, I'm with the High Command.
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I had an Original Rare Breed FRT trigger several years ago. The rifle I set up was a Bushmaster 16” barrel A Brownell’s steel lightweight carrier A Wolff XP action spring A GUTTED buffer I was getting around 1,200 rpm FLAWLESSLY Fast forward to now, I purchased a DTT 3 position FRT. I tried it with the same set up as above, NO GO! So I wound up installing a standard carbine buffer, now it’s 100% using M193 Federal ammo at around 1,100 rpm |
"When trading bullets it is better to give than to receive" _____________________
"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." - George Orwell
"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." - George Orwell
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Originally Posted By hrt4me: great, that is perfect for the aesthetic I want, thank you Yes it is absolutely it! Initially I didn't care about the aesthetic and liked the fact that it came with an ambi safety...right up until I got it installed and realized how janky, vague and sloppy it was (there's that combination of three adjectives again, I'm sound like a broken record!) and that it did not strike me as something for serious/duty use. Mike's MIL-spec safety fixes all of that and is day and night better, period! Originally Posted By PursuitSS: I had an Original Rare Breed FRT trigger several years ago. The rifle I set up was a Bushmaster 16” barrel A Brownell’s steel lightweight carrier A Wolff XP action spring A GUTTED buffer I was getting around 1,200 rpm FLAWLESSLY Fast forward to now, I purchased a DTT 3 position FRT. I tried it with the same set up as above, NO GO! So I wound up installing a standard carbine buffer, now it’s 100% using M193 Federal ammo at around 1,100 rpm Thank you for posting that and your findings are interdasting to say the least, that is a HIGH ROF, that's for sure! |
| For the FRT in my DOE clone, I went with a hydraulic buffer. IIRC, this is what Colt did with this model back when they made it. I've had no issues with reliability or bolt bounce through several hundred rounds. I'm told hydraulics do a much better job of mitigating bolt bounce and that seems to be the case with mine. |
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Originally Posted By TheFaz: For the FRT in my DOE clone, I went with a hydraulic buffer. IIRC, this is what Colt did with this model back when they made it. I've had no issues with reliability or bolt bounce through several hundred rounds. I'm told hydraulics do a much better job of mitigating bolt bounce and that seems to be the case with mine. I'm working on my FRT in my retro 9mm clone as well tonight. I have a KAW 10 ounce buffer, and a hydraulic on the way. I will report back with results. Edit: KAW not KAK |
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Originally Posted By ELittlefield: I'm working on my FRT in my retro 9mm clone as well tonight. I have a KAW 10 ounce buffer, and a hydraulic on the way. I will report back with results. Edit: KAW not KAK Perfect performance with the hydraulic buffer.  " />PSA complete upper PSA dedicated 9mm lower LBE gray buffer tube FRT-15L3 trigger KynSHOT Hydraulic Recoil Buffer 3.9" KVP extra power recoil spring PSA 32 round magazines Flawless performance, with surprisingly heavy recoil in FRT mode, as is one would expect with a heavy blowback design. I'm quite irked at how poorly the upper and lower match, though. I'm gonna have to do something about that. The small A1 peep sight is not suitable for FRT mode, and I'm going to replace it with an A2 insert. One of the few improvements made to the M16 during the A2 "upgrade." |
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Originally Posted By ELittlefield: Perfect performance with the hydraulic buffer. https://i.imgur.com/uzQQxPo.jpeg" target="_blank">https://i.imgur.com/uzQQxPo.jpeg PSA complete upper PSA dedicated 9mm lower LBE gray buffer tube FRT-15L3 trigger KynSHOT Hydraulic Recoil Buffer 3.9" KVP extra power recoil spring PSA 32 round magazines Flawless performance, with surprisingly heavy recoil in FRT mode, as is one would expect with a heavy blowback design. I'm quite irked at how poorly the upper and lower match, though. I'm gonna have to do something about that. The small A1 peep sight is not suitable for FRT mode, and I'm going to replace it with an A2 insert. One of the few improvements made to the M16 during the A2 "upgrade." I installed this guy, helped a lot with the recoil impulse. https://store.fm-products.com/products/fm-products-rmb-k-5397 |
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Originally Posted By ssgtcarroll: I installed this guy, helped a lot with the recoil impulse. https://store.fm-products.com/products/fm-products-rmb-k-5397 Originally Posted By ssgtcarroll: Originally Posted By ELittlefield: Perfect performance with the hydraulic buffer. https://i.imgur.com/uzQQxPo.jpeg" target="_blank">https://i.imgur.com/uzQQxPo.jpeg PSA complete upper PSA dedicated 9mm lower LBE gray buffer tube FRT-15L3 trigger KynSHOT Hydraulic Recoil Buffer 3.9" KVP extra power recoil spring PSA 32 round magazines Flawless performance, with surprisingly heavy recoil in FRT mode, as is one would expect with a heavy blowback design. I'm quite irked at how poorly the upper and lower match, though. I'm gonna have to do something about that. The small A1 peep sight is not suitable for FRT mode, and I'm going to replace it with an A2 insert. One of the few improvements made to the M16 during the A2 "upgrade." I installed this guy, helped a lot with the recoil impulse. https://store.fm-products.com/products/fm-products-rmb-k-5397 I’m going to install that second selector of yours tonight, as well as the bent trigger pin method. I just wanted to get it running 100% before I started mucking with it more! |
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Managed to get out and try a 3.8oz H buffer in the 9mm Banshee FE. This was still just a bit too heavy for the unsuppressed 115 gr FMJ. Seems like running no bolt weight and a 3oz standard carbine buffer is just right for this 115gr TulAmmo. I haven't tried any other 115gr ammo in this gun, but there might be some with a little more pep that would lock back on empty mags. The suppressed 147gr ammo runs at a really nice rate with the 3.8oz H buffer. I forgot to use my shot timer, but I'd estimate closer to 650-675 rpm. I think the 3.8oz H buffer with no bolt tuning weight is the sweet spot for the 9mm Banshee FE with 5" barrel for subsonics. This might be a little rough on components long term, but if you like that faster ROF it's probably the best option. For 147gr suppressed use and only semi with no forced reset, I'd be running an H2 or even H3 buffer to get the mildest recoil. |
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More good PCC-related information, that's great! Definitely more tuning required to get them running compared to the 5.56/.300 Blackout builds. FWIW a friend of mine tried to install one into a PSA47 and said that the paddle mag-release interfered with part of the drop in trigger and the trigger pin holes wouldn't line up. He added that other triggers work, just not drop-in/cassette style apparently. I'd be REAL curious if they'd work with CMMG's 4.6 or 5.7 Banshee, Dissent or Resolute offerings. Would NOT be cheap to feed but fascinated nonetheless! |
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I just installed my new RB FRT-15L3 in a PSA 11.5” AR pistol. Carbine gas with a H3 buffer, YHM Turbo K suppressor. I also installed the ssgtcarroll safety. I had tried the AZ Regulator in this gun and it ran great. The FRT also ran great. The single shot trigger seemed a little stiff, and I’ve only shot mil spec triggers, so that says a lot. If I was too light on the trigger in fully-semiauto mode it would only fire one shot, but all I had to do was pull it with a tad more force and it would scream. Went through 100 rounds much quicker than I would have preferred. No failures, no light strikes. Ran great with and without the suppressor. The safety from ssgtcarroll really makes the package. I didn’t even try the one that came with the FRT. |
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Originally Posted By Oldmini14jac: I just installed my new RB FRT-15 (whatever the 3 position is called) in a PSA 11.5” AR pistol. Carbine gas with a H3 buffer. I also installed sgtcarrol’s safety. I had tried the AZ Regulator in this gun and it ran great. The FRT also ran great. The single shot trigger seemed a little stiff, and I’ve only shot mil spec triggers, so that says a lot. If I was too light on the trigger in fully-semiauto mode it would only fire one shot, but all I had to do was pull it with a tad more force and it would scream. Went through 100 rounds much quicker than I would have preferred. No failures, no light strikes. When did you grab one of my selectors? The first batch did not have enough clearance. Does it act the same way with the original selector? If it’s better let me know. I’ll send you one of the newer ones. |
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Originally Posted By MikeWhiskey: I'd be REAL curious if they'd work with CMMG's 4.6 or 5.7 Banshee, Dissent or Resolute offerings. Would NOT be cheap to feed but fascinated nonetheless! It would be complicated to get them to run in a Dissent because of the way the bolt is designed. No trip surface to operate the FRT. |
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Originally Posted By Jambalaya: It would be complicated to get them to run in a Dissent because of the way the bolt is designed. No trip surface to operate the FRT. Thank you for the context and scratch the Dissent! 🤣 I have a Banshee and can only speak to that but a Resolute may be a viable candidate…? 🤔 5,7/4.6 with an FRT, suppressed, would be very cool IMO. 😎 |
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Originally Posted By ssgtcarroll: When did you grab one of my selectors? The first batch did not have enough clearance. Does it act the same way with the original selector? If it’s better let me know. I’ll send you one of the newer ones. Originally Posted By ssgtcarroll: Originally Posted By Oldmini14jac: I just installed my new RB FRT-15 (whatever the 3 position is called) in a PSA 11.5” AR pistol. Carbine gas with a H3 buffer. I also installed sgtcarrol’s safety. I had tried the AZ Regulator in this gun and it ran great. The FRT also ran great. The single shot trigger seemed a little stiff, and I’ve only shot mil spec triggers, so that says a lot. If I was too light on the trigger in fully-semiauto mode it would only fire one shot, but all I had to do was pull it with a tad more force and it would scream. Went through 100 rounds much quicker than I would have preferred. No failures, no light strikes. When did you grab one of my selectors? The first batch did not have enough clearance. Does it act the same way with the original selector? If it’s better let me know. I’ll send you one of the newer ones. @ssgtcarroll My selector arrived last week. (Ordered as Mini14jac but I got hacked so I’m using this ID until the original account is restored.) It worked perfectly. I think you said this batch was new last week. Thanks for the offer though. :-) |
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Originally Posted By Oldmini14jac: @ssgtcarroll My selector arrived last week. (Ordered as Mini14jac but I got hacked so I’m using this ID until the original account is restored.) It worked perfectly. I think you said this batch was new last week. Thanks for the offer though. :-) Another satisfied @ssgtcarroll customer! No surprise there... I previously mentioned that in addition to the janky ass, sloppy AF plastic fantastic ambi safety that's included in the DTT/RBT FRT packaging I felt their trigger/hammer pins left a lot to be desired too, particularly the lateral/side to side play that seemed excessive. Attached File The top set of pins in this picture came out of my Aero Precision .300 BO build, which currently has between 2-300 rounds through it, all subsonic/suppressed. I thought this wear was...excessive. The bottom set of pins is out of my CMMG Banshee (.45). While it doesn't show any visible wear it's worth noting that despite the presence of Loc-Tite the screws were backing out of the pins. That particular gun has a slightly higher round count of between 4-500, all 220/230 grain +P ammo, suppressed. I've always been a fan of KNS Precisions anti-walk/rotation pins since they saved me from trashing an otherwise solid lower years ago that had egged out holes with their slightly larger than spec pin kit. Sooooo...I've added those to my FRT builds in addition to "red"/extra power carbine length Sprinco buffer springs on my 5.56 and .300 Blackout. The one is my 5.56 build was within spec but rather short at 10.5-inches so I figured it was good insurance. |
| What's the consensus on 16" mid-length 5.56 and FRT-15L3? Undecided on barrel just yet but I can open up port if need be. Any benefit to A5 system or is it best to stick with carbine and just try the assortment of buffer weights? |
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