Cartridges


#1

From left to right:

a) 357 Magnum case slightly necked down to 9.10 mm.
tombac soft point bullet inside transparent plastic sabot
hstp : RP 357 Magnum
b) 357 Magnum case more necked down than the first one: 8.90 mm.
tombac soft point bullet inside white plastic sabot
hstp : RP 357 Magnum
c) 44 Remington Magnum case slightly necked down to 10.95 mm.
tombac soft point bullet inside black palstic sabot
hstp : RP 44 Rem Mag

What is the name of these ctges?
Are they sacrce?
Value please.

Thanks
JP


#2

They look like Charles R. (Bob) Olsen’s “Invicta” cartridges. He saw it as the basis for achieving higher velocities in a revolver without the need to use a heavily bottlenecked cartridge case with its setback problems. The trick was that the barrel was only bored large enough for the projectile. The larger sabot/sleeve stopped against the rear of the barrel, sealing the gap between the cylinder and the barrel, adding to the possible velocity achievable.

The models he showed to the shooting press back in the early/mid-80s were built on Dan Wesson revolvers. I suspect that no one wanted to market it due to the possibility that some idiot would slip a standard cartridge into the cylinder and try to shoot it out of the smaller diameter bore.

Olsen’s US Patents can be seen online:

http://www.google.com/patents?id=Pi0uAAAAEBAJ&printsec=abstract&zoom=4&dq=4393782#PPA9,M1

http://www.google.com/patents?id=l9EsAAAAEBAJ&printsec=abstract&zoom=4&dq=4457093#PPA2,M1

KAC’s Reed Knight and John Anderson later appropriated the Invicta concept to develop a pair of suppressed revolvers. The sabot/sleeves solved the common problem with previous attempts to suppress a revolver: the escape of gas through the cylinder gap.


#3

Thanks
I remember now. Invacta you are right.
JP


#4

Are they scarce and what is the value please ?
Thanks
JP


#5

[quote=“jean-pierre”]Are they scarce and what is the value please ?
Thanks
JP[/quote]
BTT