There are examples of breech-loading arms from much earlier, by a couple of hundred years.
The British Royal Archaeological Institute, The Archaeological Journal Volume 24, 1867
By Brigadier-Gen. Lefroy, R.A.___ Examples of early rifles and firearms.
Curious breech-loading smooth-bored matchlock harquebus, dated 1537, from the Tower, class 12, No. 1. It is thus described in the catalogue:__Harquebus loading at the breech, with moveable chamber. This arm appears to have belonged to King Henry VIII. It is named, with others, in the Tower Inventory of 1679:__ “Carbine, 1; Pistol, 1; and Fowling Piece, 1; said to be King Henry VIII.” The barrel is chased and gilt. Among the ornaments are the King’s initials “H. R.” and a rose crowned, supported by two lions. The date, 1537, is engraved on the breech. The armourer’s mark is a fleur de lis, surmounted by the letters, W. H. Length of barrel 1 ft. 11 in. This arm is figured in the Archaeologia, vol. xxxi, p. 492.
Curious breech-loading smooth-bored matchlock harquebus, not later than 1547, from the Tower, class 12, No. 3. It is thus described in the catalogue:--- harquebus, with fluted barrel, of same period as the preceding. Among the carvings of the stock are the rose and fleur de lis. It is a breech-loading arm, and it is remarkable that the moveable chamber which carries the cartridge has exactly the form of that in vogue at the present day: length of barrel, 6 ft. 6 in. This is probably the arm attributed to King Henry VIII. under No. 1_ the “fowling piece” of the monarch. Both of these arms are remarkable for the resemblance of the breech mechanism in principle, to what has been lately introduced under the name of the “Snider” system, the moveable iron charge chamber being represented in the modern example by a metallic cartridge.
Spence