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History of the 3 lug

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8.4K views 14 replies 9 participants last post by  Renegade  
#1 ·
I recently tried to do some research on the history of the 3 lug and found no information. I believe MP5's were the first to use this attachment style but am unsure. Can anyone provide any background or information about the 3 lug?
 
#5 ·
Tim Bixler, a talented machinist I believe was the first to fabricate a three lug barrel on the MP5. He also held some of the first patents for a three lug mount for suppressors and flash hiders. If Mickey Finn could be found for an interview he would probably be able to offer a more detailed background on the three lug barrel.
 
#7 · (Edited)
Wow I didn't expect so little to be known about it. Thanks for some leads and directions. I hope to get some more information and will post what I find out.

Does anyone know in what year they first appeared on guns?

Also I had read from older post on another board that the original purpose was for a blank firing adapter, any truth to this?
 
#8 ·
Also I had read from older post on another board that the original purpose was for a blank firing adapter, any truth to this?
I also saw information that goes as far as saying the HK 3-lug was never designed for a suppressor but for the flash hider or the blank firing adapter. Further referencing that the KAC thread-on can was the only "official" can for an MP5 variant other than the SD and it obviously used the threads of the N variant not the 3-lug... Curious stuff
 
#10 · (Edited)
Pic of the 3 lug on tec-9, and my Pre86 MP5 non threaded barrel

I have a old AWC Tec-9 can built back in the mid 90's, with a 3 lug twist mount. The mount is etched with a SCRC name, which tell me the mount was intellectual property of Tim Bixlar and SCRC . KAC on the other hand never made or offered any cans with 3 lug mount that i know off. I have my hk book by Frank W James(project 64), I am gonna look thru. Ronzo , not all MP5 barrel s have threads, only the PDW and the Navy Barrels .
 
#11 ·
I just looked at the project 64 book. The author states the three lug was added in 1966 to the MP5 for the use of a blank firing attachment, flash hiders and grenade launcher. HK it would seem is the inventor on this. Thanks for the OP's question. I was wrong about who invented the three lug. Tim Bixler invented the MOUNT. I stand corrected.
 
#12 · (Edited)
The 3-lug was way before KAC and Reed Knight.

I recall Mickey Finn passed on a few years back but his work was all focused on the threaded barrels we put on the N model MP5's and P9S's for the SEAL's. I do not recall seeing a Qual-a-Tec can for three lug but who knows.

The designers of the MP5's have since passed as well.
I suspect it was an HK innovation but can't confirm that beyond my suspicions based on seeing the progression of the first MP5's.
Someone handy with patent searches could likely find it.

A similar question goes around about who first mounted a white light on a small arm.

G3Kurz
 
#13 · (Edited)
The Bixler patent was filed in 1988 but the 3-lug's appearance on the MP5 in 1964 predates that application by 24 years.

My patent search skills are pretty good for patents on these shores. Patent databases for international patents are a different matter. Germany's patent search site is terrible, it is government run, and there are no third party search sites like there are in the USA.