I mentioned a time or two that I purchased a Mann Accuracy Device from the CMP. The Mann Device is used by the Army and Ammo supplies to test ammo for the militar.
Mine is a 5.56 w/a Remington Action. It has a Kart Barrel. There is not much information about the Mann Device out there, and I've been working with another CMP Forum poster, Bob, on trying to find as much information as we could.
He gave me a list of "Kart" businesses and we narrowed it down to Kart Sporting Arms, the maker of the Kart 22 conversions for M1911s.
I contacted Fred Kart and discovered the maker of the my barrel was indeed Fred Kart. The Army was buying 45 match pistol barrels from Kart and couldn't figure out how he was making such accurate barrels. When they, the Army Inspectors, visited Kart Sporting Arms they were impressed to say the least. They asked about making test barrels in 5.56 when they were developing ammo for the 1:7 twist M16 barrels.
This was just after the army switched from the 'A1 to the 1:7 twist A2 M16s. They were gearing up for the First Golf War and were concerned they didn't have enough ammo.
According to Fred Kart they made aprox. 5000 barrels. The New York Shop wasn't big enough to produce the barrels so they moved to NC. The barrels were used in accuracy and pressure testing ammo.
Kart didn't make the actions, they sent the barrels to the Picatinny Arsenal, NJ where the Mann Device was made, and tested in an indoor range. Then taken to Ft Dix NJ for testing outdoors at 700 yards.
Fred Kart as mentioned didn't have anything to do with the device except the barrels, but when the Army was having problems with the accuracy of the tracer ammo, they brought Kart to NJ to help come up with a solution. Kart pointed out that the case was causing the problems, not consistent. Kart advised annealing the case at several points but the Army decided that would be too time consuming, not cost effective so I guess that's why tracer ammo isn't accurate today.
Fred Kart's discussing the case problems matches the information about case prep in the "Secrets of the Huston Warehouse" and the Army testing of Lake City's ammo in the link Bob provided ne.
Kart gave me the name John Lucianetti, from the Army who helped him with the barrels. I have a call to Mr Lucianetti who should be home later this morning.
I also sent a e-mail to the Public Relations Officer at the Picatinny Arsenal requesting any information they could provide for the Mann Device.
As a side note, when Kart made the barrels they were accurate to within 1/50,000 thousands of inch in a 20 inch barrel. The Army couldn't believe this so they brought in several air gages to confirm Kart's information.
I'll post more when I get more information.
Mann Accuracy Device:
An old photo of the Mann Device being used: