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Hughes Lockless CTA rounds.


Well-Known Member
Premium Member
During the late 1960's the Hughes Tool Company came up with a new idea in cartridge and breech design. The idea was a flat telescoped cartridge and a breech which consisted of a slot milled through a barrel (the breech was plugged). The cartridge was inserted and a pressure sleeve slid over the barrel. The sleeve withstood the pressure. No breechblock or lock was required.

Plastic cases were normally used and it did not matter if they split because the chamber was sealed by conventional piston rings between the barrel and sleeve.

The round was tried in most calibres between 5.56 and 40mm.

The photographs show 4 different 30mm rounds (which used standard GAU 8 projectiles) and a 12.7 round (photographed next to a conventional 12.9 X 99 round for scale). All INERT.



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Nice ones, Dave. I have a sectioned 12.7mm round:

You can see the way in which it worked. The small propellant charge above the primer kicks the bullet into the barrel, exposing the main propellant charges in the sides. This made sure that none of the propellant gas would escape down the barrel ahead of the bullet.
Nice rounds Tony.
Which version of the ARES is it, the one with the 89mm, 101mm or 107mm case length?
No, I've not seen the others, only on the cartridge lists.
Attached a few pictures of the 89mm with links.........plastic links!!


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