Rifles And Rifle-shooting

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The Lancaster And Enfield Rifles

The recent contest between Lieut. Wallinger and the Sergeants of the Royal Engineers, reported in our numbers for April 6th and 13th, has recalled public attention to the merits of the Lancaster rifle, especially as a service weapon. In the match at Chatham the sergeants fired with the ordinary military 577 oval-bore Lancaster carbine of the Royal Engineers, the cost of which is about £4. To match such a weapon with the highlyfinished Whitworth, costing about £25, is evidently unfair. A more equal comparison might be instituted between the Lancaster and the ordinary Enfield, because the difference in the cost of these two weapons is not very material, and the price of the Lancaster would probably be reduced to an equality with the Enfield if it were manufactured in as great numbers at the Government factories. The question then remains, is it a better rifle? A writer in the London Review, reasoning from general principles, and judging also from actual experience, answers in the affirmative; and we invite attention to the following passages from his article on the subject:—

The law which governs accurate rifle-shooting or practice is very simple. It is only necessary to establish an equation between the length and diameter of the ball, and to give to that ball an adequate rotatory motion around its polar axis, when unfailing accuracy must be the result, irrespective of the precise method by which the rotatory or rifle motion is given. That is to say, the interior of the rifle barrel may be cut into any number or any shape of grooves, or no grooves at all, so long as the equation is preserved, and the bullet acquires a proper rotatory motion, and then the accuracy in every case will be equal. The consideration, however, that must determine the proper arm for a soldier involves as first conditions that the weapon should not exceed a certain weight and dimension, and that it should be easily loaded and easily cleaned. It therefore follows, that to be easily loaded, the bearing surface, in the act of loading, should be as small as possible; and that, in the shape given to the rifling, as far as practicable, all angles should be avoided. We know no other form that so perfectly carries out this proposition as the spiral oval, inasmuch as the bearing surfaces in the act of loading are but two, and no form offers so great facilities for cleaning with the unavoidably scanty means at the disposition of the soldier during active service. This opinion seems to be borne out by the results of the Indian campaign, and by the trials at Malta, Gibraltar, and other foreign stations. In India the Enfield rifle is said to have completely “shut up” at many critical periods of the campaign. The papers and private letters and official reports teemed with complaints; yet with the same ammunition, under the same circumstances, the oval-bore rifles with which the Royal Engineers were armed never failed to perform their duty to the satisfaction of both officers and men.

When the Enfield rifle is made with a diminished bore and an elongated bullet is used, comparably with the Whitworth the effect is just as good; yet the Enfield service-rifle, as it now exists, must be regarded as an attempt to satisfy impossible conditions. The officers charged with the construction of this arm were not permitted to reduce the calibre of the weapon below a given limit. Hence the adoption of the standard bore of -577. As a consequence of this too great diameter of bore, an inherent difficulty presented itself, namely, that of securing a perfectly and unfailingly hermetical fit between the interior of the bore and the ball when driven from the barrel by the explosion of the powder. Let us examine the actual result of the imperfect conditions exhibited in the Enfield rifle. The weight of the ball is fixed at 530 grains, the charge of powder at 70 grains, the calibre, as before stated, at -577. Now, the effect of 70 grains of powder acting on the large cross-section of the ball, will not and does not give pressure sufficient to produce in every case sufficient expansion of the ball into the grooves. Careful experiment shows that not 10 per cent, of the bullets are equally and fully expanded on every side. Sometimes one groove is distinctly marked, sometimes two, and in only one-tenth of the total rounds are they fully expanded, hence the inaccuracy of the shooting of the -577 bore service-rifle.

Now, the perfect conditions of accurate practice from rifles grooved in any form may be described as follows:—That the bore should be -5 inch, the length of ball 1T2 inches, rotation or twist 1 in 18 inches, charge of powder 90 to 100 grains (No. 6), weight of ball identical, namely 530 grains. The force exerted under this condition upon the cross-section of the ball may be considered as plus, therefore there is an unfailing and unerring fit between the ball and the bore, and it arises in this way: the diminished diameter of the bore gives increased length of ball, and no wooden plug is necessary as in the service bullets to drive out the metal. The bullet is therefore an homogeneous solid of about three diameters long. In the explosion the expansive force of the powder is first exerted on the rear or posterior section of the ball (a), and the transmission of the motive force, although almost instantaneous, is nevertheless met by the vis inertiae of the mass of metal constituting the ball, exerted in the whole length (from a to b), and backed by the counter resistance of the air in the barrel.

It is at a glance evident that this resistance must be evinced in the middle portion of the bullet or part of greatest resistance (c), and consequently, by a perfectly natural expansion there, the bullet would be slightly shortened, say about onetenth of an inch, while the central portion would be increased in diameter sufficiently to fit hermetically the form of the interior of the barrel, whatever its shape might be.

When these more perfect conditions are fulfilled, not once in 500 times is there any defective expansion, the ball invariably taking the form of the rifle, and thus there results the most excellent rifle practice.

These remarks apply to all rifles of every description.

What is it these favourable conditions do for a rifle, and why do they give more accurate shooting? Having shown how the interior of the bore is perfectly fitted by the bullet, we will endeavour to trace its results. One of the main achievements in the construction of a rifle is to get a "low trajectory," that is, that the curve the bullet describes in its flight should be as near an approach to a straight line as possible, and, as a necessary sequence, a high velocity is absolutely necessary, so that gravitation may have the minimum of effect in depressing the ball in its passage. Now, the effect of diminution of the calibre achieves the first result, and by the employment of a larger charge of powder on the small cross-section of the ball, the highest velocity and the most accurate results are obtained.

With respect to the methods of rifling, it will be inferred from what we have already said that so long as the ball gets a proper "spin" on leaving the barrel, it matters not in itself how that rotation is given, whether by an hexagonal bore, as in the Whitworth, an oval, as in the Lancaster, or by three grooves, as in the Enfield. Neither is a number of grooves necessary, for if one has a sufficient grip on the bullet to turn it, the requisite condition is fulfilled. Still, there are inherent defects in the manners of grooving which may easily be shown. If the rifling be angular, there is a loss of power in effecting the expansion necessary to fill up the angles, besides the probable escape there of the propelling gas. Moreover each angle is a line of weakness to the barrel; so with any number of grooves, and proportionably to their depths are the same defects manifested. The spiral oval, therefore, of the Lancaster gun is theoretically the best, as presenting the form to which the bullet will most readily adapt itself with the slightest expansion.

That the Lancaster rifle must have great merits appears from the fact, that, before the adoption of the Enfield pattern, the Lancaster rifle, then in competition with it, was recommended in preference by four separate and distinct committees. It was submitted for approval to the Commander-in-Chief, and by him sent for final decision to Hythe. The first report from the officers of the School of Musketry there was most favourable; the second report decided in favour of the Enfield. The reason then assigned for this decision was that the balls "stripped." Subsequently, however, the following facts are said to have transpired. The first 10,000 rounds of Pritchett ammunition, with which the first trials there were conducted, were of the proper standard diameter. With these cartridges admirable shooting resulted. In the second experiment the same ammunition was not employed, the former having been made in 1853, the latter in 1854; the experimenting officers at Hythe being entirely unconscious of any difference in the ammunition, not having been informed that in the bullets made in the latter year there was a difference of -007 less in the diameter, as compared with the bullet of 1853.

This fact was not detected until a year and a-half after the final decision in favour of the Enfield, when Colonel (then Captain) Fitzroy Somerset tested the pattern of the Royal Engineer oval-bore carbine. It is easy to see that the diameter of the diminished Pritchett bullet being less than the proper standard, it would, in many instances, especially when there was any excess of hardness in the lead, pass out of the barrel without acquiring a rotatory motion, that is, it would not sufficiently expand to fill the interior of the barrel, whether of a Lancaster or any other rifle.

That the Whitworth is too expensive for army use, and requires more delicate treatment than it is likely to get in actual service, we think few will question, and the tests should therefore be applied to the Lancaster and Enfield or other patterns respectively, which are fitted for the rough usage of warfare. The way of doing this, however, will not be by rifle-matches, but by firing from a fixed rest, with equal quantities of powder, and with bullets of the same weight and cast, thus making all such conditions equal, and leaving the test open only to the respective merits of the weapons themselves.

The preceding remarks refer to two different questions:

1. Which is the best proportion between the diameter and the length of an elongated rifle-shot to be fired from any rifle? And,

2. What are the merits of the Lancaster or oval-bore rifle?

As to question No. 1, we are far from agreeing with the author, that the proportions of his best bullet are preferable to all others.

The rifles which, so far, have given the best results—the Swiss and the Whitworth—have both a smaller calibre than 0 5, and a greater proportional length of shot. We cannot, however, here enter into a discussion on a point of such a general nature.

As to question No. 2, we cannot see what positive evidence the author gives of any superiority of the Lancaster rifle over the Enfield. That the carbines of the Engineers "shut up" less often than the Enfield rifles of the infantry, is easily explained by the fact that the infantry are a hundred times more numerous, in any army, than the Engineers; and that the latter do not use their carbines once when the line use their rifles a hundred times; because Engineers are there for other purposes altogether than to act as infantry.

That a long and heavy expansion-shot, hollowed out sufficiently at the rear end, with a full charge, can be made to take almost any shape of rifling, is proved in the instance of the Whitworth; here the amount of expansion required is extremely great, and still the bullet takes the hexagonal shape at its rear end. No doubt, therefore, such a bullet can be made to expand sufficiently to fill up an oval bore, if the difference of the two diameters be not too great. But why on that account the Engineer carbine should be better than the Enfield is more than we can perceive. The ideal bullet of our author has nothing whatever to do with this carbine—it would not fit it; and if even with a reduction of calibre, our author considers an increased charge of 90 to 100 grains of powder necessary to make his bullet fully take the oval bore, we think that looks much like a silent admission that the present charge of 70 grains does not always ensure a full expansion of the bullet in the oval bore of the Engineers' carbine.

Our author does not say what is to become of the increased recoil from the increased charge; still we know that 80 to 90 grains give, in the Whitworth, a not very pleasant amount of recoil, which, in rapid firing, very soon affects the steadiness of aim.

The uncommonly good results given by the Engineers' carbine in the Chatham match, as well as some exceedingly good shooting with Lancaster rifles by private gentlemen, mentioned at times in the press, make it desirable that the capabilities of the oval-bore expansion rifle, and its fitness for a service weapon, should again be tried. We, for our part, believe that it will be found to have its faults too, and that the principle of the rifling is a very secondary matter indeed in military muskets. Instead of quibbling with the Enfield about such minor matters, why not come to the point at once, and say that its greatest and most important defect is its large calibre? Change that, and you will find all other improvements but matters of detail.