Colt applied for a patent for "Tin Foil Cartridges" March 28,1851.The Eley patent for the tin foil cartridges was dated June 9,1855 and issued to William Eley and Samuel Colt.
Eley also had an earlier patent,February 1855,for an "improvement in manufacture of ball cartridges"-
"The improvement consists of a mode of fixing flexible cases(for receiving charges of powder) to balls,particularly conical ones;for which purpose,a projecting tang is cast or formed on each ball,and on such tang a paper or flexible case is fixed,by means of a perforated disc placed on the tang,in such a manner as to shut the end of the case between the disc and the ball when the tang is subjected to pressure,so as to upset it's end,and thus to fix the case and disc to the ball."
The Colt-Eley Patent-
A.D. 1855, June 9.”” N° 1324.
COLT, Samuel, and ELEY, William Thomas. ”” " Improve-
" ments in the manufacture of cartridges."
The bullet is cast with a rebate and an annular groove at its rear
end. The powder-case is formed of sheet foil, and the caps are
secured by waterproof cement. The case, when charged, is attached
to the bullet by cement and pressure. A layer of grease is run
round the cartridge at the junction of the powder-case and bullet.
The cartridge may be enclosed in an outer case, and a tape
is attached to the rear end, by means of which it may be readUy
torn off.