Here's the previous thread which has a photo of my George Brayton strap-gun with four trunnions:
http://www.gboreloaded.com/forums/index.php?topic=137119.0 I just mentally did an inventory of the breechloading inventor's models I own, most of which are in the vault, but here are the names anyway. There are a couple not listed as they are as-yet not identified. Most all of these have been mentioned if not pictured on this forum by me over the past few years:
Inventor Type of Gun
W.G. Armstrong Typical Armstrong Screw-tigtened wedge, gravity recoil check field gun
George Brayton Strap gun, 4 trunnions, one each 90 degrees around
C.F. Brown Reciprocating bolt driven by carriage wheel (impractical)
John M. Cochrane Rotary multi-chambered, chambers in horiz. plane
Alexis Hebert ditto
W.W. Hubbell Rotary breech similar to "French 75mm"
Potter Cylindrical Plug breech, special projectile and carriage
L.C.T. Weber Strap gun, very complex, patented under carriage design