W.W. GREENER on AMMUNITION

CHAPTER IV

AMMUNITION

THE British .22 bore rim-fire rifles are usually chambered to take the " long-rifle " ammunition. There are five distinct kinds of this ammunition in general use, all varying as regards external dimensions. The nomenclature employed to distinguish them is not very satisfactory, they are called " Short," " Long," " Short-rifle," " Long-rifle," and " Extra-long."
The best results are obtained by using the 40-grain bullet ammunition, which should always be used in competitions, the chamber and turn of rifling in British Miniature rifles having been arranged to suit this cartridge. For short ranges the " short rifle "
G " brand of cartridge will be found satisfactory. This cartridge was introduced by the author in 1906, when it was found that a short case gave excellent results up to the 50 yards range, provided a bullet long enough to take the rifling, and a suitable propellant were used. The turn of the rifling in modern .22 bores is much too quick to shoot the short 30-grain bullet accurately (most commonly a pitch of one turn in 16 inches - Ed.) , and with this ammunition one is apt to get an occasional wide shot, due to " stripping." It may be employed for the beginner's practice, but after the first few lessons he would do well to discard it in favour of the " G " Short-rifle "* or " Long-rifle " cartridges.
The constant use of the " Short thirty" ammunition in a rifle chambered for " Long rifle " cartridges causes erosion of the chamber, destroying the accuracy of the weapon, and rendering it useless with both Long rifle and Short cartridges.
The " Extra-long " ammunition should never be used, except in rifles especially chambered for thisclass of ammunition, in fact, the cartridge cannot be inserted into ordinary rifles, without effort. The manufacturer is often asked to build rifles especially to suit the " short " ammunition. Some makers adopt the plan of merely chambering their rifles, especially for the " Short " cartridge when required, but very little advantage is to be obtained by so doing.
Not only are there, as previously stated, five distinct varieties of .22 bore ammunition, but there are more than a dozen well-known brands, and the variations between them in external dimensions, quality of metal, and velocity, are considerable. It is the author's rule to make his rifles a tight fit for the largest brand of ammunition, and in this way gas escape, and consequent bad shooting, is avoided when using cartridges of smaller dimensions. One thousandth of an inch variation in the diameter of the cartridge case or bullet, is sufficient to cause difficulty in loading or extraction.
It is better to use tightly fitting cartridges so long as they can be pushed into the chamber by the thumb without too much effort. Other conditions being equal, such will give better shooting results than cartridges which slip easily into the chamber. Some cartridges will do this yet owing to the thinness or softness of the metal, combined with high pressure powder, will expand to such an extent that they stick in the chamber after firing and require considerable effort to extract them. It is here that the Martini system is so useful. One seldom finds a cartridge case, however tight, that cannot be extracted with the Martini Service rifle, provided reasonable pressure is put in the extractor. Most rifle clubmen are afraid of the Martini lever ; it was never intended, as all old soldiers know, to open like a snuff box. The lever should be dropped smartly using force, if necessary, for there is little likelihood of anything breaking.
The variations in the thickness of the cartridge metal used also necessitate a different weight of blow from the striker to suit each kind. The thin metal of the cases with some cartridges requires a light blow or there is a risk of piercing the case, and thus causing a " blow back." On the other hand, if the striker is not long enough or the blow insufficiently hard, one may get miss-lires with cartridges of harder metal. Here again the manufacturer has to strike the happy medium.

While on the subject of " Blow-backs " it may be advisable to mention that there is no real danger from these when using the Martini system of breech action. The breech block is broad and extends well beyond the rim of the cartridge affording ample support to its base and directing any escaping gas vertically upwards, or downwards into the action where it escapes in front of the guard. The action work being completely enclosed in the " shoe " or breech body renders gas escape back wards an impossibility.

The illustrations show the actual size of a Martini Service rifle block in conjunction with the base of a •22-bore cartridge, and the direction taken by the gas, in comparison with the small amount of support given to the cartridge by the head of the bolt in a bolt-action rifle which latter is sometimes still further weakened by the fitting of a double extractor.

A frequent cause of missfire with the Martini action is the collection of fouling on the nose of the striker. This is forced through the striker hole, and gradually forms a hard ring round the front of the striker inside the block, where it acts as a buffer and prevents the full force of the striker being expended upon the cartridge. Another difficulty easily remedied when one knows the cause is occasioned by small particles of dirt falling between the extractor and face of the barrel ; this prevents the extractor going properly into position, jambs the breech block, and is a common cause of missfire. It is only necessary to clean this part of the action to make it function properly.

Never mix the brands of ammunition, or commence to shoot with smokeless ammunition and finish with black or vice versa. It not infrequently happens that an inexperienced shot borrows a " round " of another brand from his neighbour to finish his competition ; such a proceeding is likely to end in disaster. Some factory made tests with an American smokeless cartridge show that it shoots 'kin. lower at 25 yards than the latest issue of K.N. (a difference of six minutes of angle), quite sufficient to give an " outer " if used with a rifle sighted for the English brand.
Both makes gave excellent shooting, but upon making velocity tests the American was found to give 300ft. secs. lower muzzle velocity than the standard of 1,050 ft. secs. fixed by the author for the sighting of his rifles.
Gas escape, from whatever cause, is very likely to make bad diagrams and generally causes the group to " string " vertically due to the irregular velocity. The defect should be immediately remedied either by changing the brand of ammunition or by returning the rifle to the maker who can generally correct it in a few minutes.
One can readily understand that it is a simple matter for a •22-bore cartridge to leave the factory loaded with cap fulminate and bullet only. Where the fulminate is sufficiently strong as is the case with the foreign cartridges, the bullet is blown through the barrel and nothing more serious than a " miss " is the result, where, however, weaker fulminate is used, the bullet is lodged in the barrel and in the excitement of shooting the fact that the shot has not reached the target is unnoticed by the shooter, then when the next shot is fired both bullets are driven out of the barrel, but in nearly every case the barrel is " ring bulged." If this bulge is midway down the barrel, no immediate defect is detected in the shooting, but if at the muzzle erratic shooting is shown immediately, and in either case a new barrel will eventually be required.
The shooter should always state, when ordering a rifle, what ammunition he proposes to use in it, or if he has no preference he should ask his rifle maker to advise him on this point. In this way he will probably save himself much annoyance and in any case will greatly facilitate the maker's efforts to give him complete satisfaction.