British MkII** Short Rifle

  • Country: United Kingdom
  • Ignition System: Centrefire
  • Calibre: 577 Snider

The Snider is one of my favourite conversion systems, it was adopted by Great Britain, France, Denmark, Portugal and The Netherlands at a time when cash strapped governments were seeking ways to convert vast amounts of muzzle loading rifles into breechloaders firing metallic cartridges. The Snider conversion is just one of many solutions to that simple problem and on this sight you will a good variety and in most cases it was adopted as a stopgap or temporary solution whilst the design/selection of a new breech loading firearm was in the works.

Focussing on the British Snider, it can be said that the intention was also to adopt the conversion as a temporary measure, although it turned out to serve the empire for close to 20 years, with Sniders being converted using the wide range of percussion “Enfield” rifles as the base and also rifles being made from new. The Snider was widely distributed from 1866 onwards until being phased out gradually with the introduction of the Martini-Henry.

The base conversion as invented by Jacob Snider required a receiver shoe to be mounted to the barrel in which a door hinged to the right side of the receiver was mounted. This door is the breech block which houses the firing pin which is angled to transmit the force of the percussion hammer to the cartridge primer. As well as being hinged to the receiver, the breech block, when swung open, can be pulled to the rear in order to actuate the extractor to at least partially extract the cartridge or spent case. The breech block could then return forward under the action of a spring coiled about the hinge pin, the spring itself is protected by a telescoping sleeve. Note that the cartridge was only extracted and not ejected. The user had to tilt the rifle and let the spent cartridge drop free.

The breech block was initially held shut by a ball détente (MkI, MkI*, MkII*, MkII**) before the introduction of a sprung locking latch integral with the left side of the block actuated by a thumb piece (MkIII).
The stock had to be machined to accommodate the receiver shoe but not enough to compromise strength. The percussion lock remained unchanged although the hammer striking angle was modified and the cupped hammer face was sometimes reduced to a flat striking surface. All in all the conversion was cheap and pretty fool proof.

This particular rifle is a private purchase rifle either for a civilian or volunteer. It is newly made rather than being a conversion of an ealier rifle. Although it is identical to the MkII** short rifle, it does not have any acceptance stamps indicating military service. The barrel is proofed and the lock is dated 1870 and features a royal crown but not the royal cypher, which leads me to think that ordnance parts were probably used in the making of this rifle. Another sign of civilian manufacture is the acknowledgement of the Snider patent on the top of the breech block. The rifle has five groove rifling generally known as “fast twist” rifling which is standard for this pattern. It is considered more accurate than the usual three groove “slow twist” rifling. There is also a leather firing pin protector chained to the trigger guard which allows dry firing without damaging the hammer or the firing pin.

The cartridge is known as .577 Snider. The first cartridge used had a brass base joined to a paper wrapped brass foil body. Eventually, as manufacturing techniques improved, this was changed to a fully drawn brass cartridge. With the early cartridges there was a risk of rupture, and gases could theoretically flow under the breech block and cause it to slam open, this was one of the reasons why the breech block mechanism was refined over time to be more positive. With modern brass this is very unlikely to occur using the appropriate loads.

The bullet was a Minié type bullet using a wooden plug, or tin/iron cup in the base cavity to help expansion. Modern Minié design has done away for the need for these. I personally use a 15.24mm (.60”) round ball pushed by 50grns of Swiss N°3 powder to great effect and I have not yet felt the need to experiment with Miniés. Not all Sniders will chamber such a large ball, that will depend on the chamber dimensions, which vary a lot from rifle to rifle so it is best to take a chamber cast before investing in moulds.