BMP MP5K reverse stretch bolt and locking piece
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The reason I ask is because of a conversation I had with an employee at BMP. I called niki and asked about a part list for the BMP MP5KFS and if a RCM bolt and a #28 locking piece would run suppressed and unsuppressed. She put me on hold and an employee told me I should buy the BMP bolt and use a #16 locking piece. I was also told that if I used any other combination that I would have to send the barrelled receiver back to have the barrel repressed into the trunion. It kind of sounded like he was pushing the BMP parts to complete my build.
I am no expert and I know a few have built these up and I just wanted to know what parts I would have the best luck with,Ronnie.
I am no expert and I know a few have built these up and I just wanted to know what parts I would have the best luck with,Ronnie.
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I call horse-pooey. Give me a call. I cant vouch for the esoteric requirements for the BMP/SW, however, what can assure you is that this is the receipe based on HK proven guidelines for the PDW. The RS has the physics closer to a PDW and I have personal experience with the setup with our guns.
ron,
we had weapons run fine with both LP's already.....suppressed & un-suppressed. Start with a standard K #16. Keep a #28 in your "box". Switch out when & as needed. Different ammo types & weights will function totally different as well as suppressed. Are you planning on running handloads? Are you planning on running sub-sonic while suppressed to get the maximum benefit from your suppressor. Or will you just shoot what you brought? In my experience the mk9k can seems to be the least picky.
Dj
we had weapons run fine with both LP's already.....suppressed & un-suppressed. Start with a standard K #16. Keep a #28 in your "box". Switch out when & as needed. Different ammo types & weights will function totally different as well as suppressed. Are you planning on running handloads? Are you planning on running sub-sonic while suppressed to get the maximum benefit from your suppressor. Or will you just shoot what you brought? In my experience the mk9k can seems to be the least picky.
Dj
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Thanks for the replies. I will definitely call you Chopstix. I bought my MK9K and it is my favorite suppressor. I have it on my 9MM AR15 SBR and will run it on the BMP RS. Here in Vegas we can get Winchester 147 gr super X that is subsonic through a ten inch barrel suppressed.
I have been using the search function and just read the thread on the Dakota RS. Awesome thread.
Moving forward and learning,thanks guys.
I have been using the search function and just read the thread on the Dakota RS. Awesome thread.
Moving forward and learning,thanks guys.
Totally necro bumping this thread as it's very relevant to my current issue.
I just got an RS gun in with the 110 locking piece and am using it with the MK9K. It gassed me pretty badly with 124gr that was running sort of trans-sonic out of the gun. I still have to try some 147gr. It now looks like Germany is recommending MP5-Ks with the 100 degree part and as per Chopstix comments that looks like a good bet. My issue is that I'm probably going to run a mix of 115 unsuppressed, 124 suppressed and not, and 147 suppressed and I really don't want to go swapping locking pieces all the time.
What is my best bet for those ammo combinations? 100º or 80º.... 110º is out because I need to be able to see while shooting
and the only 90º I've found is the MP5-40 which apparently does not fit... Too bad because it seems like that's the part I would want
I just got an RS gun in with the 110 locking piece and am using it with the MK9K. It gassed me pretty badly with 124gr that was running sort of trans-sonic out of the gun. I still have to try some 147gr. It now looks like Germany is recommending MP5-Ks with the 100 degree part and as per Chopstix comments that looks like a good bet. My issue is that I'm probably going to run a mix of 115 unsuppressed, 124 suppressed and not, and 147 suppressed and I really don't want to go swapping locking pieces all the time.
What is my best bet for those ammo combinations? 100º or 80º.... 110º is out because I need to be able to see while shooting
and the only 90º I've found is the MP5-40 which apparently does not fit... Too bad because it seems like that's the part I would want
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Este,I got my BMP RS running my MK9K working great. I tried it FA with a good buddies' registered sear and no hiccuPs of any kind. I am using a 100 HK locking piece,an HK bolt head and BPP -6 rollers. RCM bolt carrier and BMP recoil rod. I went to -6 rollers and the bolt gap is at .022".I am at 111 days pending on my form 1. I bought a HK#28 locking piece for an arm and half a leg but have yet to use it as the gun runs great,smooth. So far I have ran 115,124,and 147 subsonic and a variety of reloads and JHP and have not had any issues. I run HK mags and I did change out the BMP cocking tbe support for HK. I am in this clone about 2200 dollars. PM me if you need additional info. Anything for a silencertalk buddy. YMMV ,Ronnie
Ronnie,
Awesome. I'll give the 100 a try and I still have to measure bolt gap. I'm hoping for a drastic change from the 110, because it was pretty awful!
I have a recoil rod similar to the BMP, might be one actually... Have you noticed a second stage stop or like a slight hold up when racking the charging handle back? Like 3/8" before the bolt is all the way back it gets a little tension I need to pull through. I had a thought it might be the recoil rod having those allen head screws on it. I might have to investigate an IGF or a cut down factory rod. It might be the carrier or something else, not sure yet. Figured I'd ask because we have similar setups, your BMP is pretty much the same as my DJ Getz gun.
Awesome. I'll give the 100 a try and I still have to measure bolt gap. I'm hoping for a drastic change from the 110, because it was pretty awful!
I have a recoil rod similar to the BMP, might be one actually... Have you noticed a second stage stop or like a slight hold up when racking the charging handle back? Like 3/8" before the bolt is all the way back it gets a little tension I need to pull through. I had a thought it might be the recoil rod having those allen head screws on it. I might have to investigate an IGF or a cut down factory rod. It might be the carrier or something else, not sure yet. Figured I'd ask because we have similar setups, your BMP is pretty much the same as my DJ Getz gun.
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Este, I did have a drag spot when racking the action back. I took my trigger box to leon at CenterMass here in Vegas and he changed out the ejector spring and the ejector axle and the action was a lot smoother. There was some crud in the ejector spring hole in the trigger box that I cleaned out with some Barnes and a Q tip. WOrks like a champ now.
I'll try the FBI trigger pack from my fullsize, thanks!
Hmmm..... No luck on the trigger pack. I get pretty much the exact same feel with my german FBI pack and the US pack feels fine in my fullsize. I'm not sure what else it could be really...
I don't like the BMP style recoil rod AT ALL, so maybe I'll investigate that next
I don't like the BMP style recoil rod AT ALL, so maybe I'll investigate that next
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I really don't think the recoil rod is the culprit. You may want to try the reverse stretch recoil rod made by Dakota Tactical. Adam Weber at HKparts has them for forty dollars plus shipping.
Wait, you don't or you do think?
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