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FRT optimized 9mm AR? (Page 2 of 2)
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Originally Posted By dredeagle: So, the solid buffer runs your 300? That'd be surprising. I think the buffer is the obvious candidate for your stoppage. How did you determine it was not reseting? Can you describe the specific details of your stoppage? Hammer charged or hammer down? Failure to reset would indicate 2nd and 3rd position are performing identically. Is this actually what you are finding? No, it has a Tromix H3 with loose weights. |
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Originally Posted By ELittlefield: Can you be a little more detailed when you say the trigger does not reset? You're in FRT mode, you pull the trigger and a round fires, what is the state of the gun now? Is a round chambered? Is the hammer forward? Anything else we should know? I'm going to be recommending the KVP 10 ounce buffer, with 4 tungsten sliding weights, but I want to make sure I understand your malfunction. https://www.joeboboutfitters.com/Kaw-Valley-Precision-Tungsten-Blowback-Buffer-10oz-p/kvp-buffer-10oz.htm Originally Posted By ELittlefield: Originally Posted By leemozoid: Installed a Partisan Disruptor in my AR9 tonight. Did a test run and semi function was perfect but in the 3rd position the trigger would not reset. BCG/buffer weight are 23.3 oz however the buffer doesn't have sliding weights. Thoughts on what to change to get it running as well as it does in my .300BO? Can you be a little more detailed when you say the trigger does not reset? You're in FRT mode, you pull the trigger and a round fires, what is the state of the gun now? Is a round chambered? Is the hammer forward? Anything else we should know? I'm going to be recommending the KVP 10 ounce buffer, with 4 tungsten sliding weights, but I want to make sure I understand your malfunction. https://www.joeboboutfitters.com/Kaw-Valley-Precision-Tungsten-Blowback-Buffer-10oz-p/kvp-buffer-10oz.htm It is ejecting the fired case, chambering a new round but the hammer is following the bolt into battery and not resetting the trigger. I tried the Tromix H3 (weight was 20.8 oz) and it did the same thing. Function is perfect in semi mode. |
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Originally Posted By leemozoid: It is ejecting the fired case, chambering a new round but the hammer is following the bolt into battery and not resetting the trigger. I tried the Tromix H3 (weight was 20.8 oz) and it did the same thing. Function is perfect in semi mode. Originally Posted By leemozoid: Originally Posted By ELittlefield: Originally Posted By leemozoid: Installed a Partisan Disruptor in my AR9 tonight. Did a test run and semi function was perfect but in the 3rd position the trigger would not reset. BCG/buffer weight are 23.3 oz however the buffer doesn't have sliding weights. Thoughts on what to change to get it running as well as it does in my .300BO? Can you be a little more detailed when you say the trigger does not reset? You're in FRT mode, you pull the trigger and a round fires, what is the state of the gun now? Is a round chambered? Is the hammer forward? Anything else we should know? I'm going to be recommending the KVP 10 ounce buffer, with 4 tungsten sliding weights, but I want to make sure I understand your malfunction. https://www.joeboboutfitters.com/Kaw-Valley-Precision-Tungsten-Blowback-Buffer-10oz-p/kvp-buffer-10oz.htm It is ejecting the fired case, chambering a new round but the hammer is following the bolt into battery and not resetting the trigger. I tried the Tromix H3 (weight was 20.8 oz) and it did the same thing. Function is perfect in semi mode. Are you able to positively know that the trigger is not resetting, as opposed to resetting, and then releasing and hitting the bolt while it rebounds? To back up a minute, are you familiar with bolt/carrier bounce as it affects FRTs? |
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Originally Posted By ELittlefield: Are you able to positively know that the trigger is not resetting, as opposed to resetting, and then releasing and hitting the bolt while it rebounds? To back up a minute, are you familiar with bolt/carrier bounce as it affects FRTs? Originally Posted By ELittlefield: Originally Posted By leemozoid: Originally Posted By ELittlefield: Originally Posted By leemozoid: Installed a Partisan Disruptor in my AR9 tonight. Did a test run and semi function was perfect but in the 3rd position the trigger would not reset. BCG/buffer weight are 23.3 oz however the buffer doesn't have sliding weights. Thoughts on what to change to get it running as well as it does in my .300BO? Can you be a little more detailed when you say the trigger does not reset? You're in FRT mode, you pull the trigger and a round fires, what is the state of the gun now? Is a round chambered? Is the hammer forward? Anything else we should know? I'm going to be recommending the KVP 10 ounce buffer, with 4 tungsten sliding weights, but I want to make sure I understand your malfunction. https://www.joeboboutfitters.com/Kaw-Valley-Precision-Tungsten-Blowback-Buffer-10oz-p/kvp-buffer-10oz.htm It is ejecting the fired case, chambering a new round but the hammer is following the bolt into battery and not resetting the trigger. I tried the Tromix H3 (weight was 20.8 oz) and it did the same thing. Function is perfect in semi mode. Are you able to positively know that the trigger is not resetting, as opposed to resetting, and then releasing and hitting the bolt while it rebounds? To back up a minute, are you familiar with bolt/carrier bounce as it affects FRTs? Yes, I'm familiar with bounce but I'm not sure how I can diagnose between the two conditions? Do I need a more powerful spring to help push the bolt into battery faster so when the hammer does fall the bolt is in battery? |
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Originally Posted By leemozoid: Yes, I'm familiar with bounce but I'm not sure how I can diagnose between the two conditions? Do I need a more powerful spring to help push the bolt into battery faster so when the hammer does fall the bolt is in battery? Originally Posted By leemozoid: Originally Posted By ELittlefield: Originally Posted By leemozoid: Originally Posted By ELittlefield: Originally Posted By leemozoid: Installed a Partisan Disruptor in my AR9 tonight. Did a test run and semi function was perfect but in the 3rd position the trigger would not reset. BCG/buffer weight are 23.3 oz however the buffer doesn't have sliding weights. Thoughts on what to change to get it running as well as it does in my .300BO? Can you be a little more detailed when you say the trigger does not reset? You're in FRT mode, you pull the trigger and a round fires, what is the state of the gun now? Is a round chambered? Is the hammer forward? Anything else we should know? I'm going to be recommending the KVP 10 ounce buffer, with 4 tungsten sliding weights, but I want to make sure I understand your malfunction. https://www.joeboboutfitters.com/Kaw-Valley-Precision-Tungsten-Blowback-Buffer-10oz-p/kvp-buffer-10oz.htm It is ejecting the fired case, chambering a new round but the hammer is following the bolt into battery and not resetting the trigger. I tried the Tromix H3 (weight was 20.8 oz) and it did the same thing. Function is perfect in semi mode. Are you able to positively know that the trigger is not resetting, as opposed to resetting, and then releasing and hitting the bolt while it rebounds? To back up a minute, are you familiar with bolt/carrier bounce as it affects FRTs? Yes, I'm familiar with bounce but I'm not sure how I can diagnose between the two conditions? Do I need a more powerful spring to help push the bolt into battery faster so when the hammer does fall the bolt is in battery? No, a stronger spring will generally exacerbate bolt bounce. Try that 10 ounce KVP buffer, with four sliding tungsten weights. I expect it will cure your problem. |
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Originally Posted By ELittlefield: No, a stronger spring will generally exacerbate bolt bounce. Try that 10 ounce KVP buffer, with four sliding tungsten weights. I expect it will cure your problem. Originally Posted By ELittlefield: Originally Posted By leemozoid: Originally Posted By ELittlefield: Originally Posted By leemozoid: Originally Posted By ELittlefield: Originally Posted By leemozoid: Installed a Partisan Disruptor in my AR9 tonight. Did a test run and semi function was perfect but in the 3rd position the trigger would not reset. BCG/buffer weight are 23.3 oz however the buffer doesn't have sliding weights. Thoughts on what to change to get it running as well as it does in my .300BO? Can you be a little more detailed when you say the trigger does not reset? You're in FRT mode, you pull the trigger and a round fires, what is the state of the gun now? Is a round chambered? Is the hammer forward? Anything else we should know? I'm going to be recommending the KVP 10 ounce buffer, with 4 tungsten sliding weights, but I want to make sure I understand your malfunction. https://www.joeboboutfitters.com/Kaw-Valley-Precision-Tungsten-Blowback-Buffer-10oz-p/kvp-buffer-10oz.htm It is ejecting the fired case, chambering a new round but the hammer is following the bolt into battery and not resetting the trigger. I tried the Tromix H3 (weight was 20.8 oz) and it did the same thing. Function is perfect in semi mode. Are you able to positively know that the trigger is not resetting, as opposed to resetting, and then releasing and hitting the bolt while it rebounds? To back up a minute, are you familiar with bolt/carrier bounce as it affects FRTs? Yes, I'm familiar with bounce but I'm not sure how I can diagnose between the two conditions? Do I need a more powerful spring to help push the bolt into battery faster so when the hammer does fall the bolt is in battery? No, a stronger spring will generally exacerbate bolt bounce. Try that 10 ounce KVP buffer, with four sliding tungsten weights. I expect it will cure your problem. Not a big fan of becoming buffer poor. I'll see what Tromix will charge me to replace the solid weight with sliding weights. It should be a heck of a lot less than $110. |
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Originally Posted By leemozoid: Not a big fan of becoming buffer poor. I'll see what Tromix will charge me to replace the solid weight with sliding weights. It should be a heck of a lot less than $110. Tromix is a great H3. You need a 9mm buffer. Cheapest solution is to read awhile. Great Reference: Suggested Reading |
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Originally Posted By dredeagle: Tromix is a great H3. You need a 9mm buffer. Cheapest solution is to read awhile. Great Reference: Suggested Reading Originally Posted By dredeagle: Originally Posted By leemozoid: Not a big fan of becoming buffer poor. I'll see what Tromix will charge me to replace the solid weight with sliding weights. It should be a heck of a lot less than $110. Tromix is a great H3. You need a 9mm buffer. Cheapest solution is to read awhile. Great Reference: Suggested Reading I have a 9mm buffer, it just has a solid weight not sliding weights. Since I'm local I want to reach out to them to see if they can replace the weight instead of investing in a new buffer. |
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"Every time a Garand ejects its clip an angel gets its wings." RIP, I-M-A-WMD
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Originally Posted By leemozoid: I have a 9mm buffer, it just has a solid weight not sliding weights. Since I'm local I want to reach out to them to see if they can replace the weight instead of investing in a new buffer. Is it the standard style where you can drive out the roll pin? You may be able to replace aluminum with steel or tungsten and leave a gap. It’s real easy. Just gotta buy or salvage weights from a spare buffer. |
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Is the CMMG FE retrofit kit really worth it? I have a regular plunger style upper I built that runs fine. I haven’t broken the ejector spring… yet. But I only have about 500 rounds through it. I’m just having a hard time spending $400 to retrofit/upgrade an already working gun. |
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Originally Posted By BuckeyeRifleman: Is the CMMG FE retrofit kit really worth it? I have a regular plunger style upper I built that runs fine. I haven't broken the ejector spring yet. But I only have about 500 rounds through it. I'm just having a hard time spending $400 to retrofit/upgrade an already working gun. |
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Originally Posted By Karankawa: Is it the standard style where you can drive out the roll pin? You may be able to replace aluminum with steel or tungsten and leave a gap. It’s real easy. Just gotta buy or salvage weights from a spare buffer. Originally Posted By Karankawa: Originally Posted By leemozoid: I have a 9mm buffer, it just has a solid weight not sliding weights. Since I'm local I want to reach out to them to see if they can replace the weight instead of investing in a new buffer. Is it the standard style where you can drive out the roll pin? You may be able to replace aluminum with steel or tungsten and leave a gap. It’s real easy. Just gotta buy or salvage weights from a spare buffer. That is an outstanding idea. I have three H buffers with sliding weights. Unfortunately 9 mm buffer doesn't have a solid weight. Although it has a roll pin, when I removed it and pulled out the rubber plug I realized that the buffer itself was solid. It was only drilled deep enough to allow the insertion of the rubber plug and roll pin. I'm being thwarted at every turn! I've got some local smiths that I can reach out to and see if they have drill presses that will allow the rest of the core to be drilled out. Ugh! 
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"Every time a Garand ejects its clip an angel gets its wings." RIP, I-M-A-WMD
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"Every time a Garand ejects its clip an angel gets its wings." RIP, I-M-A-WMD
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Originally Posted By heavyduty: Has anyone gotten a Foxtrot Mike 9mm to run reliably with a FRT? I know bolt carrier design is important, but I’ve never seen a FM in the flesh and know very little about them. I bought a VFM-9 upper and a Mike-9 stripped lower. I put a Schmid trigger group and a standard super safety in it. A FRT should work just as good. I used the FM A5 buffer tube and RMB buffer. I took the steel weight out of the RMB and replaced it with the tungsten weights and spring from a Vltor buffer. This gave me about a 12 plus ounce dead blow buffer. I did use a couple washers to center the super safety lever but this is about all I did as far as modifying. I have put about 1500 rounds through is so far and it runs great. It is one of the best running AR9s I have shot. https://www.youtube.com/shorts/dhQ3wDwFTM8 |
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Originally Posted By BuckeyeRifleman: Is the CMMG FE retrofit kit really worth it? I have a regular plunger style upper I built that runs fine. I haven't broken the ejector spring yet. But I only have about 500 rounds through it. I'm just having a hard time spending $400 to retrofit/upgrade an already working gun. |
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FRT optimized 9mm AR? (Page 2 of 2)
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