The four groove rifle taking a ‘double belted ball’ has long since thought to be the creation of Major (later Colonel) John Jacob, of the Bombay Artillery (Commandant of the Sinde Irregular Horse), who published his ‘Rifle Practice’ in 1855. In it he refers to experiments with a four grooved rifle, taking a ball ‘with two bands round it’, the results of which experiments were placed with the Indian Government in 1846. However, in 1842, the great William Metford rears his head in a letter to the Naval and Military Gazette and writes at length about experiments he has made with a rifle ‘cut with four grooves so as to take a double-belted ball’. In February 1840, he suggested the system to Woolwich and Waltham Abbey, where ‘Mr. Austen and Mr. Lovell admitted that the four-groove had never been tried’ at either of those establishments. While doubting the benefits of a four-groove rifle, these two luminaries said they would construct a four-groove rifle and submit it for testing at the Board of Ordnance. Metford seems to have heard nothing more on the subject by 1842. This published reference predates Jacob’s first recorded use of the double-belted ball by six years. Metford’s own claim that his were the ‘first four-groove rifles made’ confirms that he believes he invented the double-belted ball. Whether he did, or not, is a different matter, but it does seem clear that Jacob did not invent it. With thanks to Bill Flentje for the information on Metford.
- Weight: 135 gn (8.7 g)
- Diameter across ball: 0.420 in (10.7 mm)
- Diameter across belt: 0.457 in (11.6 mm)
This ball does not claim to be a Metford or a Jacob double-belted ball, nor is it recovered. The diameter of the ball is 0.420 in, making it too small for military consideration in 1840 or 1846 (the standard infantry belted ball was 0.696 in, so presumably the early double belted balls were of a similar calibre). This ball is more likely a commercially produced variety, using the system, some time after Metford and Jacob had discussed their experiments publicly. With thanks to David Harding for the projectile images.
Double-belted ball
