Page:EB1922 - Volume 31.djvu/1246

ing, not between the frames, and it is therefore necessary to use out- riggers projecting to the rear, with spades which are bedded in the ground before firing. At low elevations the gun can be fired without using the outriggers. The illustration (fig. 13) shows the carriage with the I05-mm. howitzer at the moment of recoil. The photo- graph taken with '/ sec. exposure, indicates by its sharpness the steadiness of the carriage.

The 1921 Christie automobile carriage for the U.S.A. held gun and howitzer is shown in fig. 14. It is of the type described under Artillery Motors, travelling on wheels when on the road and as a caterpillar across country. In other respects it is similar to the Holt 1921 automobile carriage.

German Field Guns. The 77-mm. field gun 96 n.A. (ng. 15; was a 15-pdr. with M.V. of only 1,525 f.s., and range of only 5,800 yd. Its best feature was its light weight, namely, 185 cwt. in action, and in open warfare it did fairly well, but as soon as trench warfare began it proved nearly useless. In 1915 a long pointed fuze for the H.E.

FIG. 16. German 77-mm. field gun, 1916.

shell increased the range by about 700 yd. As the range was still insufficient, in 1916 they issued a new field gun (fig. 16). The calibre was the same as before, but the gun was lengthened from 27-3 to 35 cals., and an upper carriage was added which allowed the gun to be elevated up to 40 degrees. This enabled a range of 11,700 yd. to be attained with a streamline shell weighing 13 lb., M.V. 2,007 f- s - As this shell had two driving-bands, the new gun had to be rifled with uniform twist. Three charges were used: a reduced charge, an ordinary charge for the i6-lb. shell, and a super-charge for the streamline shell. Owing to the use of the three charges, the fixed am- munition was replaced by separate ammunition. During the open war- fare of 1918 the long field gun, which weighed 27-5 cwt. in action, was found too heavy, and was partially withdrawn in favour of the old shorter and lighter " 96 n.A."

The field guns used by the other nations engaged in the war were of no special interest ; all were light 15-pdr. of moderate power, and all except the Austrian gun were ordinary Krupps or Schneiders.

field howitzer.

Field Howitzers. A field howitzer is a piece equal in mobility to the field gun, capable of throwing a shell of 30 to 40 lb. It was formerly expected to attain the same range as the field gun, namely about 6,000 yd. ; but now that field guns fire at 45 elevation and range 15,000 yd. it is obvious that field howitzers of equal mobility cannot throw their heavy shell to the same distance. The pre-war field howitzer had already attained its limit of range, except for such increment as could afterwards be attained by the use of streamline shell, and if the post-war field howitzer is to range farther it will have to be heavier than before. It already has been seen that in some of the new field-gun equipments, intended primarily for motor traction, the weight in action has been increased to 30 and even 32 cwt. ; and with a slight increase on the latter weight it is now possible to build a howitzer throwing a 33-lb. shell 12,000 yd.

The British 4'5-in. field howitzer was designed by the Coventry Ordnance Works and was considered to be the best weapon of its class used in the war, though it will no doubt be superseded in course

of time by a weapon of longer range. It fired a 35-lb. shell and ranged 7,200 yd. ; the weight in action was 24 cwt. The recoil was controlled by rotating valves in the piston of the hydraulic buffer and was shortened at high elevations to prevent the breech from striking the ground. The howitzer was originally designed to fire shrapnel only and gave excellent results. During the war the issue of shrapnel was discontinued owing to difficulty of supply. Thereafter the howitzer fired H.E. shell with sensitive fuzes and proved a most valuable weapon for cutting belts of barbed wire.

The French had no field-howitzer equipment in 1914 and during the war they relied mainly on howitzers of the 155-mm. class for high-angle fire. A certain number of Schneider 4'2-in. howitzers were, however, used. This fired a 35-lb. shell, ranging 6,000 yd. It was of simple construction, with constant long recoil and a long cradle extended to the rear as in the 1918 Schneider gun. It weighed only 22 \ cwt. in action. The new French field howitzer will be heavier with a split-trail carriage and range about 1 1 ,000 yd.

FIG. 18. German 1O5-mm. field howitzer, 1898-1909.

The U.S.A. likewise had no light field howitzer, and in the war its divisional artillery consisted of French 75-mm. guns and 155- mm. howitzers. The lop-lb. shell fired by the latter is too heavy to be transported in sufficient numbers for a divisional field howitzer, and the U.S.A. is now bringing out a 4-2-in. (lO5-mm.) howitzer to fire a 33-lb. shell, M.V. 1, 500 f.s., to range 12,000 yd. The howitzer is about 25 cals. long, and weighs I if cwt. It has hydro-pneumatic controlled recoil on the St. Cnamond system ; the recoil is decreased from 45 in. at zero elevation to 33 in. at 80 degrees. The carriage has a split trail and gives 30 traverse; it has a high shield. The wheels have rubber tires to allow it to be drawn by a tractor at 10 m. an hour without injury. The weight in action is 33 cwt. This piece is also mounted on a caterpillar automobile carriage.

The pre-war German field howitzer (fig. 18) was of 105 mm. (4-2 in.) cal., firing a 34-lb. shell to a range of 7,600 yd. It had rear trun-

FIG. 19. German io5-mm. field howitzer, 1916.

nions and balance spring, which in this case was not a satisfactory arrangement as the spring was liable to give on discharge, causing bad shooting. In 1916 the Germans increased the length of the piece from 12 to 22 cals., with a corresponding increase of the weight, in action from 225 to 27 cwt. The lengthened howitzer, shown in fig. 19, ranged 9,200 yd. with ordinary shell and 10,500 yd. with streamline shell. It was rear-trunnioned like its predecessors.

The field howitzers used by the other nations were mostly similar in power to the Schneider 4-2-in. field howitzer mentioned above.

Horse Artillery Guns. These are at present in a stage of arrested development, pending further experience with motor guns. A horse artillery gun must be capable of keeping pace with cavalry on the road and across country, and it is as yet uncertain whether the horse-drawn gun, the motor-drawn gun, or the gun on automobile carriage is best adapted to the purpose.

The British 13-pdr. horse artillery gun was a small edition of the 18-pdr.; the French and the Russians had similar guns, namely, Schneider guns weighing about 19 cwt. in action. The French gun fired the same ammunition as the 75-mm. field gun, with one-third