Snider-Enfield Mark II**.
The barrel has 3 grooves, not awfully deep and quite wide. Barrel length is 39 inches and the twist rate is 1 turn in 78 inches, so the bullet makes half a turn (Right) going down the tube. Grooves are .005 at the breech, .012 at the muzzle, bore diameter is .577". The bullet diameter was .573" with a very thin Minie-type skirt which did not always obturate very well; you can get much better accuracy with a .584" diameter slug. Powder charge was 70 grains of RFG No. 2 (BLACK powder; FFg is closest), bullet weight was 480 grains but it was very long from the boxwood plugs in nose and base: efforts to rebalance the bullet. There were 9 different Marks of this ammunition prior to 1869, all because they were trying to use muzzleloader solutions to a breechloader problem. Today, we would just use an oversize bullet and have fun accurately. The barrels on these were just soft brown IRON and "only" would last (by actual test) about 130,000 rounds; the STEEL barrel adopted in 1867 and made through to 1872 was a considerable improvement. STEEL barrels were used only on the Mark III and are (quite) prominently marked: they were very proud of having STEEL rifle barrels at a time when everyone else had IRON.
The "Enfield" is the place of original manufacture, the "1860" is the year it was built as a muzzleloader. These were converted in 1866 and 1867 to the configuration you have in your hands. When the supply of ML rifles was exhausted, they started to make all-new rifles with an improved breech-locking mechanism and STEEL barrels; this was properly termed the SNIDER RIFLE Mark III, the appellation "Snider-Enfield" being reserved for rifles converted from Enfield rifled-muskets by the Snider System.
Jacob Snider was a Dutch-American Jewish wine merchant who fielded this design into the British trials of 1866. The Snider system was quick and cheap to make and the rifles were out of service only a few days and back in the line for about 5 shillings and the altered rifles could put out MUCH more fire: the Snider rifle could be fired at a rate of 18 rounds per minute, by actual test. I equalled this rate of fire with my own Snider, almost exactly a century later, so I know that it can be done. Yeah, they were the "AK-47" of their day!
The Snider conversion unit was in 2 main parts, the SHOE (which today would be called a "receiver") and the BLOCK. In the early models (I, I*, II, II*, II**) the Block was held in its "closed" position by a small spring-powered STUD projecting forward and into the rear of the Block, from the rear of the Shoe. Most of the time today, this Lock does not work. You can get at it to repair it by removing the Barrel Assembly and then soaking loose the Screw in the Shoe, disassembling and repairing/replacing the Spring and possibly the Stud. This is a weak lock at best, but it is what they had. The later Mark III had a MUCH-improved Lock with a heavy Bolt contained in the Block: geometry reversed from the original pattern.
Your broken part is the NIPPLE, which was the original iron Nipple with a hole drilled through the centre to permit passage of the Firing Pin. After the rifles passed out of the military, they were sold off dirt-cheap and used by anyone and everyone..... who promptly lost the Nipple Protectors and didn't know that dry-firing the thing would wreck the Nipples, first chipping them and then mashing them flat. Solution is to replace the Nipple. They unscrew easily, but you might need penetrating oil the first time. Then beg, borrow, steal, purchase or otherwise acquire a proper Nipple Protector with its appropriate Chain to connect it to the Triggerguard Swivel. If you can't find an original Snider Nipple, you can start with a Nipple for an Enfield Pattern 1853 or 1858 and have it drilled out.
SERIALS were on the underside of the Barrel and generally are 4 figures only; this Number was supposed to be repeated on the underside of the Breechblock but you will find many with replaced, unnumbered Blocks. CHECK the Shoe and the Block for writing as well as for Proof Marks. MANY of these conversions were done by BSA: their very FIRST job as a Company. Four years later, they got one of the first contracts to build the replacement for the Snider, the Martini-Henry, and from then onwards until the end of motorcycle production and then gun production used piled Martinis as their Trade Mark.
To authenticate it as original British manufacture, just take off the Lock; one quick look will tell you. These were entirely machine-made and they are BEAUTIFUL: absolute Works of ART. Check the Butt of the rifle also for "DC" in a diamond: Canadian ownership or use mark. Also check the right side of the Butt for an Enfield Stock Cartouche. There should be well-stamped Broad Arrows just about everywhere. AFAIK, the Pathan guys never did copy the DC-in-a-diamond mark. Another mark from the same period would be the MD mark: Militia and Defence. Regimentally-marked rifles also exist: check the Buttplate and the Butt.
You can make AMMUNITION from 24-gauge brass shotgun shells, slightly necked (the Snider bore itself is a 25-gauge) and trimmed, with a .030"-thick INSERT made of coiled and glued PAPER and filling from the base of the Bullet at the bottom of the Neck, to the Base of the casing. This will prevent loading too much powder and assure consistent ignition by constricting the powder charge and assuring just enough compression for best shooting.
You have a WONDERFUL Toy, Sir!
The Snider was the VERY FIRST breechloading rifle using Central-fire ammunition to be adopted by a major Army. Sniders armed the WORLD in the early 1870s and they are an absolute BALL of fun to shoot with today. Go to the range with a set of binoculars and stand behind your buddy as he takes a couple of shots: you can WATCH THE BULLET! Serious!
Hope this helps.
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"A Snider squibbed in the jungle;
Somebody laughed and fled
And the men of the First Shikaris
Picked up their Subaltern dead
With a big blue mark on his forehead
And the back blown out of his head." ....................... Kipling, of course, "Grave of the Hundred Dead".
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, smellie !....
