Some of you may have seen this project I have been working on with my hybrid CMMG RDB (Radially Delayed Blowback) 9mm Dissent variant to make it full auto capable and tune-able which has been a huge success for me: https://uzitalk.com/forums/index.ph...l-auto-cmmg-rdb-fixed-ejector-project.100045/
Direct link on my site: https://c3junkie.com/?page_id=1733
It has been running great but of course I can't leave anything alone so I am tinkering with modifying a perfectly good brand new RCM CHF MP5K fluted barrel for use in this setup:
I tested it this AM and.....
The barrel OD is so small on the MP5 that I was worried that I wouldn't have enough shoulder for the extension so I purposely left it a little long and had some light hits. So initial testing is positive but I need to pull the barrel and face the shoulder some to tighten up the headspacing for reliable operation. Then I can hopefully get some FA cyclic rate results.
So I have also been wondering what would happen if I took a fluted MP5 barrel and turned it down to work in an UZI. Full size MP5 barrel is 8.9" and my full size UZI barrels that are 3 lugged are right at 9". So I think I could make a threaded sleeve to replicate the flange of an UZI barrel so I could put that barrel in an UZI.
Obviously none of this 'needed' and I would argue that the MP5 does NOT 'need' a fluted chamber either. One of my friends supports guns for a MG rental range and swaps their rental MP5 barrels with cheap blanks he cuts on his lathe with NO flutes and those beat up rental guns run like a champ.
This is for educational / entertainment purposes but it is interesting that in my limited testing with my hybrid CMMG RDB dissent, it runs with NO extractor installed in the bolt.
It would be really interesting if it would work in an UZI and if someone had the means to do this, you could theoretically not need an extractor in your bolt assuming your ammo goes bang...obviously you will need it to clear dud or something. Or if you have a worn out extractor, it wouldn't have to work too hard.
Or is this a bad idea and using a fluted chamber in an open bolt SMG is dumb? Anyone ever try this or see this done before?
Direct link on my site: https://c3junkie.com/?page_id=1733
It has been running great but of course I can't leave anything alone so I am tinkering with modifying a perfectly good brand new RCM CHF MP5K fluted barrel for use in this setup:
The barrel OD is so small on the MP5 that I was worried that I wouldn't have enough shoulder for the extension so I purposely left it a little long and had some light hits. So initial testing is positive but I need to pull the barrel and face the shoulder some to tighten up the headspacing for reliable operation. Then I can hopefully get some FA cyclic rate results.
So I have also been wondering what would happen if I took a fluted MP5 barrel and turned it down to work in an UZI. Full size MP5 barrel is 8.9" and my full size UZI barrels that are 3 lugged are right at 9". So I think I could make a threaded sleeve to replicate the flange of an UZI barrel so I could put that barrel in an UZI.
Obviously none of this 'needed' and I would argue that the MP5 does NOT 'need' a fluted chamber either. One of my friends supports guns for a MG rental range and swaps their rental MP5 barrels with cheap blanks he cuts on his lathe with NO flutes and those beat up rental guns run like a champ.
This is for educational / entertainment purposes but it is interesting that in my limited testing with my hybrid CMMG RDB dissent, it runs with NO extractor installed in the bolt.
It would be really interesting if it would work in an UZI and if someone had the means to do this, you could theoretically not need an extractor in your bolt assuming your ammo goes bang...obviously you will need it to clear dud or something. Or if you have a worn out extractor, it wouldn't have to work too hard.
Or is this a bad idea and using a fluted chamber in an open bolt SMG is dumb? Anyone ever try this or see this done before?
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