Mr. Metford's apprenticeship to rifle work began, as has been already said, while he was yet a boy, and he gave constant attention to it in the intervals of his engineering studies and apprenticeship. There was very little rifle-shooting done at that time, except at quite short ranges, but as early as 1852 he was carrying on long range experiments as far as 1,200 yards, as shown by the records he then kept.
Late in 1852 or early in 1853 he suggested a hollow-based bullet for the Enfield rifle expanding without a plug, which was brought out with the assistance of Mr. Pritchett, who was awarded 1,000 pounds by H.M.'s Government for this invention, on its adoption by the Small Arms Committee to whom he had offered it.
It was in 1853 that Mr. Metford discovered that a soft lead flat-backed bullet would fully expand in the rifling, and without a plug, an addition thought at that time absolutely necessary. He exhibited this bullet to the Select Committee on Small Arms, and having convinced the Committee that the bullet would expand, he was authorised to make experiments to enable him to discover whether this bullet would shoot better than the Enfield bullet. These experiments, as made by Mr. Metford, proved that there was a difference in favour of the accuracy of the Enfield bullet, though a very slight one, and he reported against his own bullet--the flattening of the back made the bullet too short.
In the year 1854 Mr. Metford experimented with bullets made of alloys of lead and tin, with the view of discovering whether any sort of alloyed bullets would, when flat-backed, rifle up by the force of the explosion, and, if so, how far the lead could be hardened while leaving enough softness to enable the energy of the powder gas to rifle it.
In the year 1854 he first discovered that all rifle barrels, when in their stocks, are bent before the bullet passes the muzzle by the agency of the explosion. While fitting a telescopic sight to his rifle, he was much puzzled to find that the rifle shot to a point quite different from that to which the axis of the barrel was pointed at the moment of pulling the trigger. Careful trial showed him that the discrepancy existed equally and in the same direction in respect to the barrel, whether the rifle was fired with the sights upright, horizontal, or upside down, and that it must therefore be quite independent of gravity. Mr. Froude suggested to him the true explanation, that it was due to the mass of the stock being unsymmetrical with the mass of the barrel. He proved that the amount of disturbance varied with variation of the charge, and thus a flood of light was let in on the idiosyncrasies of different rifles. In 1856 be found that the most curiously erratic shooting could be produced from a rifle barrel held in a. vice, quite undamaged, but with the particles of the metal put into a state of strain.
In 1854, and probably earlier, Mr. Metford was familiar with the American telescopic sights made by James, of Utica, after the design of Mr. J. Chapman, C.E., and at this time he designed and made a telescopic sight on rather different principles, which gave ample play for the elevation needed for long ranges, and which ten years of heavy recoiling had failed to damage when it was described by him in "Rifling and Rifle Sights," edited by Lord Bury for the National Rifle Association in 1864. He used telescopic sights for many years in his long range experiments, and had invented an arrangement of lenses which enabled the eye to be kept well away from the eyepiece in aiming, and so to escape damage from the recoil.
The possibility of making an explosive rifle-bullet soon engaged Mr. Metford's attention, and in the year 1856 he invented the rifle shell which bore his name, and was eventually adopted by the Government. In the year 1857 he was applied to by Colonel Dixon, the Chief of the Select Committee, to send in his explosive shell for experiment, and it, in his hands, defeated all other rifle shells tried, and was eventually exhibited as the best shell before Lord Panmure, Secretary of State for War, and others, and gave great satisfaction. This, however, was in Mr. Metford's absence, for he had recently left for India, and for the moment no such shell was adopted.
Soon after his return he was informed that the military authorities were again experimenting with rifle shell, and ho wrote desiring that, as his shell bad already taken the first place as being unfailing, simple and cheap, it might be put into competition again. It then competed against Colonel Boxer's and General Jacobs' shells and defeated them, and was finally adopted by Her Majesty's Government in 1863. The production of this shell had cost Mr. Metford much time and trouble; he had himself made 66,000 shells for the Government, as well as special machinery for turning them out, and had lived at Woolwich some time for the special purpose of making them. Further, be had not patented the invention, wishing to leave the Government in the most advantageous position, should it adopt it. Yet the War Office, which often seems to find a difficulty in distinguishing between the more crank, with an exaggerated notion of the value of some crude or useless idea, and the capable scientific man who asks only a reasonable recompense for really valuable work, awarded him, in the first place, only 1,000 pounds in full discharge of all expenses and claims in connection with the matter, a sum absolutely not sufficient to meet the actual cost to him of his experiments, and the manufacture of the bullets, with a very moderate allowance for the time expended in the work. Mr. Metford, who was the least self-seeking of men, after strongly pressing his claims for a juster treatment, was eventually awarded 1,000 pounds in addition to the reimbursement of his expenses; but, considering the value of the invention at that time, this reward can only be described as quite inadequate. Further, his work in this matter had been done under the very trying circumstances of great weariness and chronic headache, which was now his normal condition of health, so that it can be no matter for surprise that when, in 1868, the Committee on Small Arms applied to him for his views on the adoption of an arm of smaller calibre than the Enfield rifle, he did not see his way to putting his knowledge at the disposal of the War Office.
Mr. Metford used to say that an explosive bullet was justifiable, because it would make wars short, but the explosive bullet did not survive very long, for the Convention of St. Petersburgh, in 1868, declared against explosive missiles than 14 oz. weight, and in March, 1869, it was declared obsolete.