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[ARCHIVED THREAD] - Do I need a heavier buffer? (Page 1 of 2)
Posted: 8/31/2016 2:07:29 PM EDT
My 9mm carbine
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| Mr. Pig... I'm a gamer... I'm working with heavy buffers in my USPSA PCC... currently using a rifle buffer tube and a 6.2oz brass insert in a rifle buffer with NFA bumper...no last round bold hold open... so far the heavier buffers are reducing dot movement in the scope... will try a rifle buffer filled with lead shot next...I'm sure at some point I will get diminishing returns |
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You need a stronger spring! I use a Tubb .308 Flatwire spring + 13 quarters adding more force on the bolt. I also use a 5.4oz buffer. What spring are you using? Forgot about this one Using whatever spring came in my PSA glock lower, I'd guess standard carbine Ordered a tubb 308 flatwire |
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Forgot about this one Using whatever spring came in my PSA glock lower, I'd guess standard carbine Ordered a tubb 308 flatwire Quoted:
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You need a stronger spring! I use a Tubb .308 Flatwire spring + 13 quarters adding more force on the bolt. I also use a 5.4oz buffer. What spring are you using? Forgot about this one Using whatever spring came in my PSA glock lower, I'd guess standard carbine Ordered a tubb 308 flatwire Can I get a link to the spring? Would this buffer work? |
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Myself and a friend used this
http://heavybuffers.com/9q.html Ive also run mine with a standard carbine spring and buffer with 5 quarters as a spacer. Pistol calibres can be finicky and just need to fine tune it to your liking. Lighter and heavier rounds will change a little but not much. I shoot a lot of steel challenges and love it. |
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Myself and a friend used this http://heavybuffers.com/9q.html Ive also run mine with a standard carbine spring and buffer with 5 quarters as a spacer. Pistol calibres can be finicky and just need to fine tune it to your liking. Lighter and heavier rounds will change a little but not much. I shoot a lot of steel challenges and love it. Cool, Thanks! |
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You need a stronger spring! I use a Tubb .308 Flatwire spring + 13 quarters adding more force on the bolt. I also use a 5.4oz buffer. What spring are you using? Forgot about this one Using whatever spring came in my PSA glock lower, I'd guess standard carbine Ordered a tubb 308 flatwire Can I get a link to the spring? Would this buffer work? Tubb .308 flarwire spring http://www.davidtubb.com/tubb-springs/bufferspring-sr-ar10 As far as that buffer goes, it's standard length so you'd still want a spacer if you're going to have lrbho. I believe KAK and KAW both make extended 9mm buffers in the 7-8 oz. range as well as Spikes ST-9x(?) |
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I tried the tubb spring and am really happy with it
Now I can barely even see any flame on slow motion, even in the dark Another big difference I've noticed is how much cleaner it runs With a standard carbine spring it was practically dripping gunk after 100 rounds. It's running much cleaner which I attribute to the bolt staying closed longer |
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Heavier buffer is the way to go. One thing to consider with stronger springs is it also slams the bolt shut that much harder. Don't know how or if it effect longevity but mine ran perfectly with a stock carbine spring and 8oz buffer. You are correct sir....that pesky little thing called physics.......and that rat bastard Newton.....get's ya every time.... 
If you reload...the extra bolt velocity with heavier springs MAY reduce case life , and can break extractors and firing pins....Not a guarantee mind you ...but I have seen increased failures in some circumstances.... |
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I tried the tubb spring and am really happy with it Now I can barely even see any flame on slow motion, even in the dark Another big difference I've noticed is how much cleaner it runs With a standard carbine spring it was practically dripping gunk after 100 rounds. It's running much cleaner which I attribute to the bolt staying closed longer I have the same results. It runs much cleaner, even after hundreds of rounds suppressed. If you already have not, lightly grease up the outside of the buffer spring. It feels a lot smoother. The Tubb spring is naturally squared off rather than rounded, so it's more grittier. But after your lightly grease it, it feels great. You won't have to worry about cleaning it often since you have have a cleaner shooting gun! |
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Have to ask what ammo you using... Factory stuff, or handload ?
I ran into issue with handloading for my M11,, couple of my slower powder was spitting stuff out the eject port, sparks and random flash.. powder change remedy that aspect of it, though now I have a gas shield on the M11 now, but I still use powder that dont flash & debris from eject port. Titegroup is about all I use for my std 9mm loading ventures |
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OP, not trying to hijack your thread.
Question for those with experience tuning the buffer system on a 9mm build. I am currently piecing one together around a Ballistic Advantage 8.3" barrel. Muzzle device will be the Spikes Barking Spider Krink. Planning on going with either the NFA or the CMGG bolt. Looking at the Kaw Valley 7.5oz buffer and the Kaw extra power spring. Any reason to look at different components or does this pass the initial smell test? Thanks in advance! |
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OP, not trying to hijack your thread. Question for those with experience tuning the buffer system on a 9mm build. I am currently piecing one together around a Ballistic Advantage 8.3" barrel. Muzzle device will be the Spikes Barking Spider Krink. Planning on going with either the NFA or the CMGG bolt. Looking at the Kaw Valley 7.5oz buffer and the Kaw extra power spring. Any reason to look at different components or does this pass the initial smell test? Thanks in advance! My 9mm checklist always includes: 1) Metalform Magazines for assured reliability 2) Ramped bolt ( your CMMG should be ramped) 3) Un-notched AR hammer to go with ramped bolt (DPMS is example) 4) KNS stainless anti-rotation pins. (9mm is hard on pins and reciever pin holes) 5) Heavy extended length buffer (smooths out the action and recoil impulse) 6) Factory loaded 147gr. round nosed FMJ ammo. I would test fire with standard carbine spring first. If GTG, stick with that. Extra power springs can fix cycling issues but also adds energy to the bolt return. Over time this can sometimes lead to premature wear. 9mm blowback is hard on stuff. Items listed above will help midigate wear, breakage and enhance reliability. Best of luck on your project. |
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Expensive but it is the smoothest running buffer I've found YMMV.
https://www.blitzkriegcomponents.com/SearchResults.asp?Cat=1823 |
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@ Indrid-Cold: When you say "heavy extended length buffer", what length do you suggest? Also, what weight spring did you have in mind? The standard Colt 2 piece mechanical 9mm buffer is about 3-1/4" long. The various extended buffers offered are all about 4 to 4-1/8" or about .875" longer then standard length. Standard spec carbine springs have always worked for me even with an 8 oz. buffer and factory loaded ammo. |
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My 9mm checklist always includes: 1) Metalform Magazines for assured reliability 2) Ramped bolt ( your CMMG should be ramped) 3) Un-notched AR hammer to go with ramped bolt (DPMS is example) 4) KNS stainless anti-rotation pins. (9mm is hard on pins and reciever pin holes) 5) Heavy extended length buffer (smooths out the action and recoil impulse) 6) Factory loaded 147gr. round nosed FMJ ammo. I would test fire with standard carbine spring first. If GTG, stick with that. Extra power springs can fix cycling issues but also adds energy to the bolt return. Over time this can sometimes lead to premature wear. 9mm blowback is hard on stuff. Items listed above will help midigate wear, breakage and enhance reliability. Best of luck on your project. Quoted:
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OP, not trying to hijack your thread. Question for those with experience tuning the buffer system on a 9mm build. I am currently piecing one together around a Ballistic Advantage 8.3" barrel. Muzzle device will be the Spikes Barking Spider Krink. Planning on going with either the NFA or the CMGG bolt. Looking at the Kaw Valley 7.5oz buffer and the Kaw extra power spring. Any reason to look at different components or does this pass the initial smell test? Thanks in advance! My 9mm checklist always includes: 1) Metalform Magazines for assured reliability 2) Ramped bolt ( your CMMG should be ramped) 3) Un-notched AR hammer to go with ramped bolt (DPMS is example) 4) KNS stainless anti-rotation pins. (9mm is hard on pins and reciever pin holes) 5) Heavy extended length buffer (smooths out the action and recoil impulse) 6) Factory loaded 147gr. round nosed FMJ ammo. I would test fire with standard carbine spring first. If GTG, stick with that. Extra power springs can fix cycling issues but also adds energy to the bolt return. Over time this can sometimes lead to premature wear. 9mm blowback is hard on stuff. Items listed above will help midigate wear, breakage and enhance reliability. Best of luck on your project. This is the reason I'm really liking the Tubb flat wire .308 spring. It has almost the exact same compressed force as a carbine spring (16lbs) but it has almost 12lbs holding force vs. a carbine springs 7lbs. This means it helps keep the bolt closed longer without having additional return force slamming the bolt closed |
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The standard Colt 2 piece mechanical 9mm buffer is about 3-1/4" long. The various extended buffers offered are all about 4 to 4-1/8" or about .875" longer then standard length. Standard spec carbine springs have always worked for me even with an 8 oz. buffer and factory loaded ammo. Quoted:
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@ Indrid-Cold: When you say "heavy extended length buffer", what length do you suggest? Also, what weight spring did you have in mind? The standard Colt 2 piece mechanical 9mm buffer is about 3-1/4" long. The various extended buffers offered are all about 4 to 4-1/8" or about .875" longer then standard length. Standard spec carbine springs have always worked for me even with an 8 oz. buffer and factory loaded ammo. Kaschi, will your setup have LRBHO? If not I wouldn't bother with an extended buffer, just a heavy buffer The longer buffer is to help prevent breaking bolt catches when you have LRBHO IMO I'd rather have the extra bit of bolt/buffer travel |
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I have the same results. It runs much cleaner, even after hundreds of rounds suppressed. If you already have not, lightly grease up the outside of the buffer spring. It feels a lot smoother. The Tubb spring is naturally squared off rather than rounded, so it's more grittier. But after your lightly grease it, it feels great. You won't have to worry about cleaning it often since you have have a cleaner shooting gun! Quoted:
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I tried the tubb spring and am really happy with it Now I can barely even see any flame on slow motion, even in the dark Another big difference I've noticed is how much cleaner it runs With a standard carbine spring it was practically dripping gunk after 100 rounds. It's running much cleaner which I attribute to the bolt staying closed longer I have the same results. It runs much cleaner, even after hundreds of rounds suppressed. If you already have not, lightly grease up the outside of the buffer spring. It feels a lot smoother. The Tubb spring is naturally squared off rather than rounded, so it's more grittier. But after your lightly grease it, it feels great. You won't have to worry about cleaning it often since you have have a cleaner shooting gun! I coated it with TW25 before I installed it 
I also usually coat the inside of my buffer tube with a thin film of TW25 every once in a while Thanks again for the spring recommendation |
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Expensive but it is the smoothest running buffer I've found YMMV. https://www.blitzkriegcomponents.com/SearchResults.asp?Cat=1823 Do hydraulic buffers wear out? |
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Do hydraulic buffers wear out? Quoted:
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Expensive but it is the smoothest running buffer I've found YMMV. https://www.blitzkriegcomponents.com/SearchResults.asp?Cat=1823 Do hydraulic buffers wear out? Everything wears out
If you mean do they wear out faster than a standard car buffer, I would venture a guess at yes. That being said, most people won't "wear out" a standard buffer in their lifetime. How many rounds per month do you typically shoot? |
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LWRC UCIW short buffer tube and standard short buffer(around H weight) with their flat-wire spring. Runs fine but still thinking of getting a heavy buffer and trimming the rubber bumper back. http://i.imgur.com/SLkyT1I.jpg Yeah that pic looks like you could definitely slow things down a little more 
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This is the reason I'm really liking the Tubb flat wire .308 spring. It has almost the exact same compressed force as a carbine spring (16lbs) but it has almost 12lbs holding force vs. a carbine springs 7lbs. This means it helps keep the bolt closed longer without having additional return force slamming the bolt closed Quoted:
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OP, not trying to hijack your thread. Question for those with experience tuning the buffer system on a 9mm build. I am currently piecing one together around a Ballistic Advantage 8.3" barrel. Muzzle device will be the Spikes Barking Spider Krink. Planning on going with either the NFA or the CMGG bolt. Looking at the Kaw Valley 7.5oz buffer and the Kaw extra power spring. Any reason to look at different components or does this pass the initial smell test? Thanks in advance! My 9mm checklist always includes: 1) Metalform Magazines for assured reliability 2) Ramped bolt ( your CMMG should be ramped) 3) Un-notched AR hammer to go with ramped bolt (DPMS is example) 4) KNS stainless anti-rotation pins. (9mm is hard on pins and reciever pin holes) 5) Heavy extended length buffer (smooths out the action and recoil impulse) 6) Factory loaded 147gr. round nosed FMJ ammo. I would test fire with standard carbine spring first. If GTG, stick with that. Extra power springs can fix cycling issues but also adds energy to the bolt return. Over time this can sometimes lead to premature wear. 9mm blowback is hard on stuff. Items listed above will help midigate wear, breakage and enhance reliability. Best of luck on your project. This is the reason I'm really liking the Tubb flat wire .308 spring. It has almost the exact same compressed force as a carbine spring (16lbs) but it has almost 12lbs holding force vs. a carbine springs 7lbs. This means it helps keep the bolt closed longer without having additional return force slamming the bolt closed Why the Tubb .308 spring vs their AR15 spring? Guessing it's has more holding force then their AR15 offering even though it references "extra power" but no numerical spec. |
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Why the Tubb .308 spring vs their AR15 spring? Guessing it's has more holding force then their AR15 offering even though it references "extra power" but no numerical spec. Quoted:
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OP, not trying to hijack your thread. Question for those with experience tuning the buffer system on a 9mm build. I am currently piecing one together around a Ballistic Advantage 8.3" barrel. Muzzle device will be the Spikes Barking Spider Krink. Planning on going with either the NFA or the CMGG bolt. Looking at the Kaw Valley 7.5oz buffer and the Kaw extra power spring. Any reason to look at different components or does this pass the initial smell test? Thanks in advance! My 9mm checklist always includes: 1) Metalform Magazines for assured reliability 2) Ramped bolt ( your CMMG should be ramped) 3) Un-notched AR hammer to go with ramped bolt (DPMS is example) 4) KNS stainless anti-rotation pins. (9mm is hard on pins and reciever pin holes) 5) Heavy extended length buffer (smooths out the action and recoil impulse) 6) Factory loaded 147gr. round nosed FMJ ammo. I would test fire with standard carbine spring first. If GTG, stick with that. Extra power springs can fix cycling issues but also adds energy to the bolt return. Over time this can sometimes lead to premature wear. 9mm blowback is hard on stuff. Items listed above will help midigate wear, breakage and enhance reliability. Best of luck on your project. This is the reason I'm really liking the Tubb flat wire .308 spring. It has almost the exact same compressed force as a carbine spring (16lbs) but it has almost 12lbs holding force vs. a carbine springs 7lbs. This means it helps keep the bolt closed longer without having additional return force slamming the bolt closed Why the Tubb .308 spring vs their AR15 spring? Guessing it's has more holding force then their AR15 offering even though it references "extra power" but no numerical spec. Here's a list of how much force a spring puches on the bolt (closed and open). This was taken from Tubb's video: A2 (old) - 7.6lb closed, 14.5lb open A2 (new) - 9.1lb closed, 16.7lb open Tubb Flatwire - 10.5lb closed, 16.3lb open Tubb .308 Flatwire - 13lb closed, 16.7lb open SpringCo (White/standard) - 8.3lb closed, 16.3lb open SpringCo (Red/Enhanced) - 10.5lb closed, 18.4lb open SpringCo (Orange/Extra) - 13.9lb closed, 24.8lb open I have tried the SpringCo Red, but the Tubb .308 seems better as it has more force on bolt close where it's needed most. I also use about 13 quarters, H3 buffer, NFA Bolt and my bot catch is going good. |
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This is relevant to my interests, I also shoot PCC in USPSA and SC. Had my first match with my now-functioning PCC (came from PSA with a bad trigger, threw that thing away) and it was a blast but it is definitely cycling hard, is extremely dirty, and spits out a lot of crud/oil from the ejection port. Since I shoot lefty, this is my primary concern along with accelerated parts wear. I have the factory PSA buffer and spring. I also have an NFA bolt. Which buffer are you guys recommending? I'm gonna pick up a Tubb's AR10 spring and I'm thinking about the Spike's extended 9mm buffer. |
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Quoted: Here's a list of how much force a spring puches on the bolt (closed and open). This was taken from Tubb's video: A2 (old) - 7.6lb closed, 14.5lb open A2 (new) - 9.1lb closed, 16.7lb open Tubb Flatwire - 10.5lb closed, 16.3lb open Tubb .308 Flatwire - 13lb closed, 16.7lb open SpringCo (White/standard) - 8.3lb closed, 16.3lb open SpringCo (Red/Enhanced) - 10.5lb closed, 18.4lb open SpringCo (Orange/Extra) - 13.9lb closed, 24.8lb open I have tried the SpringCo Red, but the Tubb .308 seems better as it has more force on bolt close where it's needed most. I also use about 13 quarters, H3 buffer, NFA Bolt and my bot catch is going good. What do you mean by "13 quarters" here? Edit: Nevermind, figured it out. You mean putting quarters in the buffer tube. Got it. I'm guessing that wouldn't be a good idea if you're running an extended length buffer like the Spike's or Slash's right? |
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This is relevant to my interests, I also shoot PCC in USPSA and SC. Had my first match with my now-functioning PCC (came from PSA with a bad trigger, threw that thing away) and it was a blast but it is definitely cycling hard, is extremely dirty, and spits out a lot of crud/oil from the ejection port. Since I shoot lefty, this is my primary concern along with accelerated parts wear. I have the factory PSA buffer and spring. I also have an NFA bolt. Which buffer are you guys recommending? I'm gonna pick up a Tubb's AR10 spring and I'm thinking about the Spike's extended 9mm buffer. Do you have lrbho on your gun? |
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What do you mean by "13 quarters" here? Edit: Nevermind, figured it out. You mean putting quarters in the buffer tube. Got it. I'm guessing that wouldn't be a good idea if you're running an extended length buffer like the Spike's or Slash's right? Quoted:
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Here's a list of how much force a spring puches on the bolt (closed and open). This was taken from Tubb's video: A2 (old) - 7.6lb closed, 14.5lb open A2 (new) - 9.1lb closed, 16.7lb open Tubb Flatwire - 10.5lb closed, 16.3lb open Tubb .308 Flatwire - 13lb closed, 16.7lb open SpringCo (White/standard) - 8.3lb closed, 16.3lb open SpringCo (Red/Enhanced) - 10.5lb closed, 18.4lb open SpringCo (Orange/Extra) - 13.9lb closed, 24.8lb open I have tried the SpringCo Red, but the Tubb .308 seems better as it has more force on bolt close where it's needed most. I also use about 13 quarters, H3 buffer, NFA Bolt and my bot catch is going good. What do you mean by "13 quarters" here? Edit: Nevermind, figured it out. You mean putting quarters in the buffer tube. Got it. I'm guessing that wouldn't be a good idea if you're running an extended length buffer like the Spike's or Slash's right? What would be the point in doing that? |
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Here's a list of how much force a spring puches on the bolt (closed and open). This was taken from Tubb's video: A2 (old) - 7.6lb closed, 14.5lb open A2 (new) - 9.1lb closed, 16.7lb open Tubb Flatwire - 10.5lb closed, 16.3lb open Tubb .308 Flatwire - 13lb closed, 16.7lb open SpringCo (White/standard) - 8.3lb closed, 16.3lb open SpringCo (Red/Enhanced) - 10.5lb closed, 18.4lb open SpringCo (Orange/Extra) - 13.9lb closed, 24.8lb open I have tried the SpringCo Red, but the Tubb .308 seems better as it has more force on bolt close where it's needed most. I also use about 13 quarters, H3 buffer, NFA Bolt and my bot catch is going good. Quoted:
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OP, not trying to hijack your thread. Question for those with experience tuning the buffer system on a 9mm build. I am currently piecing one together around a Ballistic Advantage 8.3" barrel. Muzzle device will be the Spikes Barking Spider Krink. Planning on going with either the NFA or the CMGG bolt. Looking at the Kaw Valley 7.5oz buffer and the Kaw extra power spring. Any reason to look at different components or does this pass the initial smell test? Thanks in advance! My 9mm checklist always includes: 1) Metalform Magazines for assured reliability 2) Ramped bolt ( your CMMG should be ramped) 3) Un-notched AR hammer to go with ramped bolt (DPMS is example) 4) KNS stainless anti-rotation pins. (9mm is hard on pins and reciever pin holes) 5) Heavy extended length buffer (smooths out the action and recoil impulse) 6) Factory loaded 147gr. round nosed FMJ ammo. I would test fire with standard carbine spring first. If GTG, stick with that. Extra power springs can fix cycling issues but also adds energy to the bolt return. Over time this can sometimes lead to premature wear. 9mm blowback is hard on stuff. Items listed above will help midigate wear, breakage and enhance reliability. Best of luck on your project. This is the reason I'm really liking the Tubb flat wire .308 spring. It has almost the exact same compressed force as a carbine spring (16lbs) but it has almost 12lbs holding force vs. a carbine springs 7lbs. This means it helps keep the bolt closed longer without having additional return force slamming the bolt closed Why the Tubb .308 spring vs their AR15 spring? Guessing it's has more holding force then their AR15 offering even though it references "extra power" but no numerical spec. Here's a list of how much force a spring puches on the bolt (closed and open). This was taken from Tubb's video: A2 (old) - 7.6lb closed, 14.5lb open A2 (new) - 9.1lb closed, 16.7lb open Tubb Flatwire - 10.5lb closed, 16.3lb open Tubb .308 Flatwire - 13lb closed, 16.7lb open SpringCo (White/standard) - 8.3lb closed, 16.3lb open SpringCo (Red/Enhanced) - 10.5lb closed, 18.4lb open SpringCo (Orange/Extra) - 13.9lb closed, 24.8lb open I have tried the SpringCo Red, but the Tubb .308 seems better as it has more force on bolt close where it's needed most. I also use about 13 quarters, H3 buffer, NFA Bolt and my bot catch is going good. When you say extra length buffer are you referring to a 9mm specific buffer? |
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Krylandcelo, Drew Red... I'm too cheap to buy a $30 spring, so have been working with rifle length buffers and an A1 stock for USPSA PCC with a 16" carbine and NFA modular bolt...with 147 hand loads at about 1000fps I get less scope dot movement with a 7.5oz buffer and a stock rifle spring... that would be a good starting point if you have similar bullet weight and velocity... SBR7-11 suggested a 5/8" brass dowel which gives him a 7oz buffer...
if someone could fill a rifle buffer with #9 lead shot, it would be appreciated for reference... or a carbine buffer with yellow cake uranium 
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If this question was for me, yes, I mean a larger-than-standard-carbine-size buffer such as a 9mm/blowback specific buffer. Examples: Spike's ST-9X, Slash's 9Q Quoted:
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When you say extra length buffer are you referring to a 9mm specific buffer? Meant for joshv06 but thanks for confirming my question. Figured that was what he was referencing but wanted to make sure. |
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Meant for joshv06 but thanks for confirming my question. Figured that was what he was referencing but wanted to make sure. Quoted:
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When you say extra length buffer are you referring to a 9mm specific buffer? Meant for joshv06 but thanks for confirming my question. Figured that was what he was referencing but wanted to make sure. Sorry, I don't believe I ever mentioned an extra length buffer. Indrid-Cold did, though |
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Sorry, I don't believe I ever mentioned an extra length buffer. Indrid-Cold did, though Quoted:
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When you say extra length buffer are you referring to a 9mm specific buffer? Meant for joshv06 but thanks for confirming my question. Figured that was what he was referencing but wanted to make sure. Sorry, I don't believe I ever mentioned an extra length buffer. Indrid-Cold did, though You are correct. My bad. |
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You are correct. My bad. Quoted:
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When you say extra length buffer are you referring to a 9mm specific buffer? Meant for joshv06 but thanks for confirming my question. Figured that was what he was referencing but wanted to make sure. Sorry, I don't believe I ever mentioned an extra length buffer. Indrid-Cold did, though You are correct. My bad. I believe others have already answered it, but since your question was directed toward me, I'll do a recap. The extra length buffers were designed for the 9mm setup. 9mm does not require as much bolt travel as 5.56. The added length limits that travel and reduces tendency of bolt catch breakage. Some use a stack of quarters or a machined spacer behind the recoil spring to accomplish that task without replacing the buffer. |
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*snip*
I believe others have already answered it, but since your question was directed toward me, I'll do a recap.
The extra length buffers were designed for the 9mm setup. 9mm does not require as much bolt travel as 5.56. The added length limits that travel and reduces tendency of bolt catch breakage. Some use a stack of quarters or a machined spacer behind the recoil spring to accomplish that task without replacing the buffer Thanks for the clarification. 9mm is about as tricky to figure out as building an AR10, so trying to make sure I understand the system before randomly buying parts. |
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Quoted: Has anyone used the Tubbs 308 spring combined with a heavy buffer such as Spike's 8.5 oz. ST-9X? Wondering if that's too much combined with the extra force the Tubbs spring provides. I'm also running an NFA bolt which I believe is a couple ounces heavier than most on the market.... So this should be a pretty close to "as heavy as possible" build. With the exception of Slash's 12 oz monster buffer. |
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LWRC UCIW short buffer tube and standard short buffer(around H weight) with their flat-wire spring. Runs fine but still thinking of getting a heavy buffer and trimming the rubber bumper back. http://i.imgur.com/SLkyT1I.jpg I have used the UCIW buffer tube and the best combo for a 5.5" barrel was a Wolff +10% power spring with H3 (5.4 oz?) buffer weight with the bumper grinder down a bit until the bolt clear the catch by 1/4". In my 10.5" barrel and suppressed I was not getting enough mass behind the bolt as evidenced by a louder port bark and dirtier brass walls from earlier bolt opening. I switched to a regular buffer tube and used an extended 8oz weight for that barrel length and its all good. I did order a 10oz weight from KAK to try it out too, still in the mail. |
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Krylandcelo, Drew Red... I'm too cheap to buy a $30 spring, so have been working with rifle length buffers and an A1 stock for USPSA PCC with a 16" carbine and NFA modular bolt...with 147 hand loads at about 1000fps I get less scope dot movement with a 7.5oz buffer and a stock rifle spring... that would be a good starting point if you have similar bullet weight and velocity... SBR7-11 suggested a 5/8" brass dowel which gives him a 7oz buffer... if someone could fill a rifle buffer with #9 lead shot, it would be appreciated for reference... or a carbine buffer with yellow cake uranium See this post http://www.ar15.com/forums/t_3_15/700796_son_of_9mm_buffer.html&page=1#i7264169 |
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I do not. Quoted:
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Do you have lrbho on your gun? If you don't have lrbho you don't need a spacer If you have a heavy enough standard length buffer you don't need an extended 9mm buffer either Both of those are only necessary to prevent breaking bolt catches |
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Krylandcelo, Drew Red... I'm too cheap to buy a $30 spring, so have been working with rifle length buffers and an A1 stock for USPSA PCC with a 16" carbine and NFA modular bolt...with 147 hand loads at about 1000fps I get less scope dot movement with a 7.5oz buffer and a stock rifle spring... that would be a good starting point if you have similar bullet weight and velocity... SBR7-11 suggested a 5/8" brass dowel which gives him a 7oz buffer... if someone could fill a rifle buffer with #9 lead shot, it would be appreciated for reference... or a carbine buffer with yellow cake uranium I posted the following in another thread but I think I might try a rifle buffer in a carbine tube. I just need one I can measure since I already cut the only one I had down to 9mm length. I was thinking about the whole 9mm bolt travel thing and how it's way more travel than what is actually necessary to chamber and extract. So I tore down my hipoint 9mm and weighed the "slide" and it's roughly 26oz. (Need a better scale) The recoil spring is miniscule compared to an AR spring, maybe ½" x 6" The recoil "buffer" is a ¼" thick piece of rubber. So... I figured out how much bolt travel was needed to reset the hammer and figured I could shorten the stroke by about 2" I made a 1" long 1" diameter rubber "plug" and sandwiched it between two ½" thick 2" diameter delron spacers. I gave it a try and it worked! I had a few different springs and buffer weight combinations to try but I ran out of light The biggest difference I noticed was that the recoil was more of a straight back push and staying on target was easier. When running with full bolt travel the recoil seemed to almost have a twist to it (can't think of a better way to describe it) |
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Quoted:
Has anyone used the Tubbs 308 spring combined with a heavy buffer such as Spike's 8.5 oz. ST-9X? Wondering if that's too much combined with the extra force the Tubbs spring provides. It's going to depend on total bolt/buffer weight I think. I've run 22oz total weight with the tubb spring pretty light 147 grain loads and had no issues Seems most 9mm bolts are around 16oz so that would put you at 24.5oz I'd be willing to guess it would work |
[ARCHIVED THREAD] - Do I need a heavier buffer? (Page 1 of 2)
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