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Legend

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Brennan wrote:

Not wishing to get a reputaion as a nay sayer!

On economics the problem often is that the energy cost even in modern plant is geometric (ie multiplicative) as temperature & pressure rises. In the 19th Century the relationship was often Exponential!!! This with a number often well over 2 for the exponent!
...
Short of emergency / war measures or new &/or breakthrough plant I suspect not much use would have been made of faster process at higher temps & pressure! Especialy as increased pressure & temperature would decrease the time between plant failures &/or replacement.




Maybe, but I think the late nineteenth, early 20th century plant we are discussing used steam for both heat and pressure. Maybe someone can tell from http://bakelite_world_2001.tripod.com/itsbakeliteyouknow/id12.html (2/3 of the way down, can't link to the picture by itself). Pretty mature technology if so (and in many respects we would be battling to recapitulate it today).

But anyway, basically agree, but with the quibble that what is hedged as "convenient" in the patent specification would be expected to be well under-spec for the ultimate production plant. But remembering that Baekeland was wealthy by virtue of previous patents so wasn't necessarily confined by the usual restrictions in his experimentation/pilot plant/demonstration... There you go, two bob each way! laughing.gif

-- Edited by Rectalgia on Thursday 20th of May 2010 10:54:01 AM

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Legend

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As promised, the upgraded table with bullet (projectile) weight (grains) MV (feet per second) and 200 yard mid-range trajectory (inches). That last figure is how HIGH above the sighting line the bullet passes at 100 yards. It is a rough guide to trajectory - the lower the figure the "flatter" the rifle shoots. What must be appreciated is that at 300 yards the bullet would be something like 2.5 to 3 times that figure LOW. And it gets worse from there.

The MRT figures are a little problematical - generally they assume a sighting line starting 0.5 to 0.75 inches above the bore line but there are sure to be some errors introduced for exact comparison - certainly there is no cause to be excited about supposed difference in the MRT of a few tenths of an inch. This is all affected by the muzzle velocity and the ballistic coefficient of the projectile. Even 'ballistic coefficient' is subject to differences in determination but the 200 yard MRT is largely empirical - the observed figure for what that is worth (of course different 'observers' see different things). But it is a best try.

It is a bit of a dog's breakfast even in other matters, there are a few post-WW1 types there where it might be useful to show the difference/evolution. I have generally shown the later bullet where they changed immediately prior to or during WW1. Ideally I should show both but I have elected to keep this version to one page. I have added the Ross rifle for Canada (it was used in significant numbers) and the Lee 6mm for the USA (that was still in ships' armouries until the 1920s). I have taken out the Garand rifle, left in the US .30 carbine but refrained from showing the WW2 assault rifles although their comparatively light projectiles at intermediate velocities could add to the picture. That is getting too far into WW2 I think.

[Edit] Amended entries for Austria and for Hungary
[Edit 2] Some cartridge designations expanded to differentiate.
[Edit 3] Squeezed in US M17 Enfield - significant WW1 weapon for the US, some interesting differences compared to the Springfield despite same calibre. This table version is ready to go to further page(s) as needed.

-- Edited by Rectalgia on Monday 31st of May 2010 11:02:26 AM

-- Edited by Rectalgia on Monday 31st of May 2010 04:47:28 PM

-- Edited by Rectalgia on Tuesday 1st of June 2010 07:31:26 AM

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Lieutenant-Colonel

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Many thanks. The table shows how sinister us Imperials & the French were compared to every one else. The 1 sinister US entry being actually commisioned by us Imperials, so only a single sinister Norwegian entry as an outlier. 

Have always wondered about the chioce of sinister or dexter for the twist?

Regards,

Brennan 



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Legend

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Brennan wrote:
...Have always wondered about the chioce of sinister or dexter for the twist?
Haven't tracked down the "reason" myself!

The physics of it all is neutral of course, there will be a slight drift in the direction of the spin but the effect is tiny, nothing compared to wind drift. Nevertheless I vaguely recall some made argument for some sort of superiority. Perhaps Mr Enfield was left-handed? Or determinedly anti-superstitious, the "widdershins" twist would be viewed as inherently evil in some circles but that all depends on whether one is behind or in front of the muzzle, at several levels of meaning.biggrin.gif

The Colt Government M1911/M1911A1 .45 ACP pistol has a left-hand twist as well and I don't think we can blame that on the Brits. Oh, OK, why not? Haven't forgiven them for Wilmansrust myself, 12 June 1901 lives on as a day of infamy in this household and the anniversary fast approaches. Unfounded supposition will more than suffice, by way of retribution.laughing.gif

-- Edited by Rectalgia on Monday 7th of June 2010 05:55:54 AM

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Commander in Chief

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Hi Steve,

things didn't went that smoothly always I guess, isn't the Breaker Morant/Bushveld Carabineers-story another example? Not that I want to stirr up feelings between British and Australians, being an outsider...well thinking about that...Boers were also called Dutchmen by leading British officers, not that strange.
And everyone seems to have had a share in 'non military' killings...the victimised Boers too (Modderfontein, massacring native people).
A reason for German sympathy in the Netherlands, certainly in 1914 was the British 'invasion' in South Africa, considered as an injustice of the first degree. Though sympathic feelings turned more pro Allies after the news of the atrocities in Namur, Liege trickled in.
But Paul 'Oom' Kruger was considered here as a hero, I think many Dutch felt frustrated their  government (and navy!)  hadn't the power to intervene.

regards, Kieffer

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Legend

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Nobody likes being "bossed around", it is in the Australian culture (or the stereotype, more accurately) to show that more openly than most. And small organisations 'learn' more quickly than large. The stereotype of 'regimentation' as a way for troops to conduct themselves is more than a little at odds with the hard-won principles of Sir John Moore one century before (knowledge of the 'trade' to all levels, initiative and instant improvisation were to be encouraged when wholly consistent with objectives all being a major part of that) so it sometimes seemed to the brow-beaten 'colonials' that the 'Colonel Blimps' of the old country were reactionary and an actual impediment to progressing to the winning of objectives. Even in their own army, the myth of 'lions led by donkeys' was sometimes strongly felt in the ranks.

That is a little unfair, the dominions were untried and unskilled at large-scale manoeuvres and arguably lacked the high-level strategic view of warfare. But mostly they were outside of the 'old boy' network and never allowed to forget it. That network works very well, when it works, but it is little substitute for the kind of professionalism at all levels taught by Moore.

When unshackled the 'colonials' did quite well, such as Lt. General Sir John Monash - first soldier to be knighted in the battlefield by the ruling Sovereign in over 200 years and none since (so that's 300 years now, more or less). And, talking of Boers and those from the 'colonies', Field-Marshall Smuts in the Second World War, respected and listened to by all in top-level strategy, including Churchill and Chief of Imperial General Staff, General Alan Brooke, two very difficult men to impress!

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Legend

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"A picture is worth a thousand words," never more so than in the world of cartridges. Unfortunately I can't post them here (they are part of Anthony G Williams' excellent article from "HISTORIC MACHINE GUN CARTRIDGES" published in the February 2009 edition of Small Arms Review magazine and copyright protected) - but I can refer to a web-published version at http://www.quarry.nildram.co.uk/Historic MGs.htm. There are found pictures and tables of fairly-well all of the cartridges referred to in the "Rifles3.pdf" table presented earlier (except for the .30 US M1 carbine round) and there are a few additional ones that aren't in that table.

Those few more are (except for the 8x52R Siamese Mauser) specialised LMG/GPMG/MMG rounds which, although of "rifle calibre" never saw wide service in infantry rifles. Except for the Dutch cartridge those are post WW1. They are the 7.92x57R Dutch, 7.92x61 Norwegian, 8x63 Swedish and 8x59 Breda (Italy).

Note - the 30-06 is also referred to as the 7.62x63 and the 7.92x57 is the same as the 8x57JS in Rifles3.pdf.

-- Edited by Rectalgia on Tuesday 8th of June 2010 07:58:18 AM

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Legend

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And here is the .30 M1 Carbine cartridge, together with its source, a photo of the Garin range of wildcats based on necking that case down (I'm sure Mr Garin won't mind). In fact there are off-the-shelf rifles and pre-formed cartridges available for all five so they are not strictly-speaking wildcat cartridges. Attributing the .30 to the Garin range as is done in the caption is an error - that is of course the original US Government military cartridge or a direct copy of it.

-- Edited by Rectalgia on Wednesday 9th of June 2010 06:31:17 AM

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Legend

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A marginal note to:
Rectalgia wrote:
...Anthony G Williams' excellent article from "HISTORIC MACHINE GUN CARTRIDGES" published in the February 2009 edition of Small Arms Review magazine ...
Talking of machine guns, the question of quantitative comparisons was addressed much later in history - I note the concept of "muzzle horsepower" which came into use in WW2, largely through the analyses of London Times Air Correspondent (Sir) Peter Masefield, with particular reference to aircraft use in which application the relative performance of various rifle-calibre and heavy MG calibres and cannon armaments were of critical importance. "Power" takes into account the volume of fire as well as the energy (individual mass and velocity of projectiles) of the weapons system - and its scaling (as either horsepower or kilowatts) is quite convenient for instant appreciation.

The 'per-gun' kinetic power is simply found by multiplying the muzzle energy in foot pounds (per Williams' HISTORIC MACHINE GUN CARTRIDGES) by the cyclical firing rate divided by 60 (that is, change to rounds per second) and dividing the answer by 550 to bring to horsepower. It is even more straightforward in metric, if the ME is given in joules (1 j/s = 1 watt).

Hard these days to credit just how influential that young (British) man was in the field of US fighter aircraft armaments and for how long - probably more responsible than anyone else for the USA sticking with their .50 cal MGs long after everyone else switched to cannon and, perhaps, their many and ultimately abandoned searches for a superior .60 cal. HMG round. Well, not entirely wasted - the Soviet 14.5mm was/is a successful essay into that territory though not used in the end for primary aircraft armament.

This is not primarily about WW1 but it applies equally to the WW1 automatic weapons (we do love our comparisons) although it was probably less critical for most purposes in WW1 - they were all well up to the primary purpose of killing the enemy in large swathes.

-- Edited by Rectalgia on Monday 1st of November 2010 08:10:56 AM

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Legend

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The elderly 11mm Gras cartridge survived well into - and beyond - WW1, in the Balkans, in Greece, etc, also in the western front as a blank to fire a French trench mortar (mentioned else where in these pages).  I have come across another use, documented in a Robertt T Buttweiler Ltd rare cartridge and accessory price guide - in practice shells for French 37mm and 57mm (6 pdr) cannon.

I don't know whether or not these "sub calibre adaptors" were actually used for training during the war. Coloured image from Bob Shell's Blog.

(PS - I wouldn't get excited about those prices in the Guide - I have no idea how old that might be)



-- Edited by Rectalgia on Saturday 23rd of April 2011 04:57:06 AM

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Legend

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Military rifles, from the cartridge point of view, are all about trade-offs in factors such as penetration, "wound channels", weight and volume of ammunition (and use of materials), recoil velocity, muzzle flash and muzzle blast, chamber pressure, barrel and chamber throat wear and exterior (projectile) ballistics.  At the end of it all, the infantryman has to be able to hit that at which he aims.  Bullet drop and wind-drift (the two are looslely linked) are the fundamental obstacles to marksmanship.  Standards of accuracy vary but aimed rifle shots in battle conditions would (I think) rarely be consistently effective at much more than 300 yards (or metres) - about 4 minutes of angle (MOA) - close to 4 inches (100 mm) grouping ability at 100 yds, in WW1/2.

I had occasion to draw up a chart of bullet drop from the "line of departure" (barrel) at 300 yards recently, showing the effect of the variables of muzzle velocity and ballistic coefficient.  There are many "ballistic coefficients", an indicator of the drag through air restance overcome by the bullet in its progress (a function of projectile form and sectional density).  I used the one used by Sierra Bullets in their exterior ballistic tables 1971-74 which is essentially the same as that used by Colonel Ingalls, US Army, pre WW1 and in turn utilised the work of Colonel Mayevski, Imperial Russian Army, on "drag zones". Sierra Bullets use far more sophisticated mehods and different coefficients these days but (without actually checking) I would be astounded if the results in this limited case would be much different to that pictured below.

Most military pointed projectiles would have had coefficients around the 0.4 mark, "boat tail" types perhaps shading into the 0.5 and slightly above region, the long, heavy round-nose types (6.5 mm Carcano etc.) around 0.2 or even lower.  The 0.1 (and lower range) is approaching the "house brick" end, the 0.7 (and above) is tending towards the "tungsten needle" end (coefficients can be greater than 1 for special projectiles).

The main appreciation I draw from the picture is of the diminishing returns on both extreme velocities and extreme ballistic coefficients.  Not obvious is the penalty in terms of longer barrels or more powder to increase velocity and (generally) faster rifling pitch leading to lower velocity and more wear to increase ballistic coefficient.  Drop from the line of departure is not the same as the drop perceived by the shooter - the shooter experiences the drop (or rise) from the line of sight which is above the departure/barrel line as mentioned in relation to the rifles table presented earlier.  But the two are related.

All in all I think it all helps to understand the evolution of military cartridges in the era of "smokeless" or "nitro" propellants.  Well, it helps me.

ExtBallistics - Drop.png

I've done a "curve fit" for the lines, shown by the equation and constants in the table.  This is essentially a "nonsense correlation" (no basis in theory) but reliable to the accuracy figure shown (or better) for interpolation of drop figures within the stated range (but no guarantees for extrapolations).  The whole of the source data is based on Sierra's own 1970s extrapolations but their "curve fitting" was far more solidly based - and subjected to real-life reality checks, with extrapolation a less risky proposition (and besides the only methodolgy then available to them).



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Legend

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I see your point about muzzle velocity increase and diminishing returns (at the second viewing - it's a lot of info to get your head round), although if you look at the figures, I'd say the difference from 2400fps to 3000fps is noticeable.
I saw a bit of a repeat of the BBC's documentary "The First World War from Above" recently, and in it a historian comments that many of the casualties of the first day of the Somme battle suffered from leg injuries from the German MG fire, saying it was as though they had been "scythed down". Given the hundreds of yards (or metres) range across many parts of No-Man's Land, this table certainly makes it look as though the German gunners might actually have been aiming at chest height.

It's an interesting chart, but do you have any idea how the different weights compare for a given muzzle velocity? Presumably the lighter bullets are the slower ones after 300 yards?

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Legend

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Depends on the BC (ballistic coefficient) TCT - the lower that number is, the lower the retained velocity, therefore retained energy. Of course heavier bullets will have more energy at the same velocity than lighter ones. In the data (extreme case) there were 300 grain bullets with the same or nearly the same BC as 40 grain bullets, therefore their trajectories and retained velocities are identical or fairly nearly.

That's more or less one way to define BC - matching trajectory means matching BC. A .458" 300 grain flat-nose bullet fired at the same velocity from a .45-70 will have practically the same drop at any range as a .223" 40 grain spire-point fired from a 22 Hornet. Their BCs are .160 and .163 respectively. Their drop from the line of departure with muzzle velocity 2400 fps is practically identical - as is their retained velocity:

Projectile/Range 50 yds 100 yds 150 yds 200 yds 250 yds 300 yds
300 gn .458" Flat -nose B.C. 0.160 0.78" 3.47" 8.55" 16.73" 28.91" 46.20"
Retained Velocity (fps) 2143 1902 1680 1479 1306 1167
40 gn .223" Spire -point B.C. 0.163 0.78" 3.45" 8.51" 16.61" 28.64" 45.66"
Retained Velocity (fps) 2147 1911 1691 1493 1321 1181

They have very different sectional densities and very different form factors. BC is related to sectional density divided by form factor and the differences in the two sets of figures fairly-well cancel each other out in this example.

Although the projectiles spend fairly-well the same time in flight (a major factor in wind-drift) the little 40-grainer will be blown about more than the 300 grainer.

Muzzle energies are 3836 ft-lb for the 300 grain and 512 ft-lb for the 40 grain. Retained energies at 300 yds are 908 ft-lb and 124 ft-lb respectively. They each shed about 76% of their initial energy fighting the air-drag in getting to 300 yards. With higher BCs that rate of loss is reduced - and the trajectory is "flatter".

[Edit] Corrected .223 RVs - must have been drunk when I entered those before.

-- Edited by Rectalgia on Tuesday 19th of June 2012 11:04:46 AM



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Legend

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Hmmm. Is it just me, or does the idea of a bullet dropping about four feet after 300 yards make it sound as if armies should ditch rifles and go back to bows and arrows? I suppose the alarming figures would seem fine if one drew up a scale diagram of trajectory, it's just that it sounds like a big drop when read.

I had a look back at the comparison table you posted much earlier in the thread, and noted that the Lee-Enfield was not a great performer in terms of trajectory - 3.5 inches rise at mid-range? The faster .30-06 rises only 2 inches according to the table; clearly the Americans found themselves a good combo.

Incidentally, I also noticed that the German Mauser G98 was listed as 8mm calibre; somewhere on the forum someone has said something about nominal diameters and actual ones, but shouldn't that 8mm read 7.92mm?

Edit - Steve, I've just noticed one of your older posts showing a photo of an M1 carbine .30 round: what surprises is the pointed bullet, as I'm sure the photo in an old Ian V Hogg book I have shows a blunt bullet - perhaps a little elongated - for the carbine. Is there a mistake somewhere, or did they change the shape at some point?



-- Edited by TinCanTadpole on Tuesday 19th of June 2012 05:37:26 PM

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Legend

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TinCanTadpole wrote:

Hmmm. Is it just me, or does the idea of a bullet dropping about four feet after 300 yards make it sound as if armies should ditch rifles and go back to bows and arrows? I suppose the alarming figures would seem fine if one drew up a scale diagram of trajectory, it's just that it sounds like a big drop when read.


The adjustment for line of sight makes a surprisingly big difference in minimising the perceived drop, even so the matter of judging range is critical. It is much better from the late 19th century compared to the old muzzle-loading days of truly "rainbow trajectories" when one commander (Colonel Hanger) reckoned of the Brown Bess that no-one was ever hit by an aimed shot at 200 yards ("... might as well fire at the moon ..."), even if a Soldier's musket was "... not exceedingly ill-bored, as many are.".

Long bows would certainly have been superior in accuracy in those days but required a lifetime of training, starting from boyhood. Popular wisdom of old held it to be too late to reach the standard if training was left until adulthood. Try a bow-pull of 200 pounds to get the idea.

Troops of all eras tend to shoot high in compensation - one commander (Colonel Belson) in the Iberian Peninsula during the Napoleonic wars famously advised his men to "be sure to fire at their legs and spoil their dancing." This is anyway the optimal tactic in chaotic battle conditions (mindful too of your earlier comment about German MG fire).

TinCanTadpole wrote:

I had a look back at the comparison table you posted much earlier in the thread, and noted that the Lee-Enfield was not a great performer in terms of trajectory - 3.5 inches rise at mid-range? The faster .30-06 rises only 2 inches according to the table; clearly the Americans found themselves a good combo.


The "thirty-aught-six" was undeniably ballistically superior to the "three-oh" but as one frustrated US soldier remarked to a Senate Select Committee, the .303 was still remarkably good at killing the enemy. The context was political opposition to the AEF in WW1 using British Lewis guns and in which that superiority of the .30-06 was extolled by a patriotic Senator. That is mentioned in more detail elsewhere (somewhere), in one of the Lewis gun topics I think.

A couple of points, the .303 not only had less powder capacity but also the standard Mk VII round was conservatively loaded - it had to serve in all climates and use in hot conditions increases chamber pressure. Also, the rear-locking Lee-Enfield rifle action was not designed for the pressures that the front-locking Mauser-types (including the .30-06 Springfields and P17s) could routinely handle. Even so, SMLE-armed British and Commonwealth troops were known to use "machine-gun" ammunition in their rifles (contrary to orders) in the belief it had a ballistic edge. Post-war (the 1938 Mk VIIIz), it certainly would have had, not sure about the WWI stuff though. It was certainly manufactured to closer tolerances to reduce stoppages in automatic weapons. There was a Mk VIIz (z = nitrocellulose powder) introduced in 1916 (List of Changes 19256 3 May 1916) but I have no actual data on performance.

Another point is, the .30-06 was a comparatively long cartridge with a 63 mm case (compared to 56 mm for the .303 and 57 mm for the German 8x57 JS - the .30-06 and the 8x57JS are identical in the size of their bases, incidentally, there's not a lot of variation in military rimless cartridge base-sizes). The longer the case, the more opportunity for jamming in automatic weapons and the more opportunity for "short-charging" in bolt-action rifles. Strange to say, it is not uncommon for soldiers under stress to fail to extract a spent round but to continually, ineffectually, re-chamber and "fire" it. I'm sure the Americans coped with this slight disadvantage admirably but the higher-capacity case did come with that small cost.

TinCanTadpole wrote:

Incidentally, I also noticed that the German Mauser G98 was listed as 8mm calibre; somewhere on the forum someone has said something about nominal diameters and actual ones, but shouldn't that 8mm read 7.92mm?


Designations vary - "8 mm Mauser", "8x57JS", "7.92 mm Mauser", even "7.9x57 mm" (Cartridges of the World, Barnes). It is all the same round, firing a .323"/8.2 mm projectile through something like a .315"/8 mm (land-to-land) tube. A slightly messy round in terms of it was originally the 8x57J, firing a .318"/8 mm projectile, presumably through a .310"/7.98 mm tube. Barrel tolerances and wear being what they are there's not much in it BUT it is generally deemed inadvisable/foolhardy to fire the later 8x57JS round in the older 8x57J rifle with the nominally tighter bore. Projectile tolerances are usually quite fine - about the only thing I can't see in all that mix is 7.92 mm but there must be an explanation somewhere, it is certainly one of the "standard" designations.
TinCanTadpole wrote:

Edit - Steve, I've just noticed one of your older posts showing a photo of an M1 carbine .30 round: what surprises is the pointed bullet, as I'm sure the photo in an old Ian V Hogg book I haveshows a blunt bullet - perhaps a little elongated - for the carbine. Is there a mistake somewhere, or did they change the shape at some point?


Well spotted, I think the picture shows a civilian version, long after the original military ammunition is past its shelf life (of about 30-40 years). As far as I know, there was just the one standard military "ball" round, the M1 with an 111 grain projectile but there were two bullet types within that one designation (gilding metal jacket and gilding metal clad steel jacket). I have only ever seen the round-nose bullet shape. There was (believe it or not) the M27 tracer round but I don't know what that looked like (except it reportedly had an orange tip)

Steve.

-- Edited by Rectalgia on Wednesday 20th of June 2012 06:38:43 AM



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Legend

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Thanks Steve, that's a comprehensive and clear answer (or series of,)

TCT

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Legend

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We shouldn't forget that exterior ballistics are only part of the story about the path of the bullet. The WW1 military rifles were constructed, in terms of the action parts, barrel, action bedding and barrel bedding doing a particular job with the varieties of ammunition expected and under the conditions anticipated following countless hours of development and large-scale trials and subsequent modifications. From the mists of time comes this observation about the SMLE No.1 Mk III/III* that goes back to the transition between the Mk VI and Mk VII cartridges - from the 215 grain round-nose to the 174 grain spire-point:
... The Lee-Enfield rifle barrel vibrates in such a manner as to reduce the differences in height between the points of mean impact of ammunition with different velocities.

For example, a Lee-Enfield fired with ammunition giving a 2,235 ft./sec. velocity shoots 12 inches lower at 200 yards than with ammunition giving 2,000 ft./sec. velocity. At 390 yards range the the points of impact with both types of ammunition are at the same height. At 1,000 yards, the 2,235 ft./sec. ammunition shoots 7 feet higher than the other.

We see, therefore, that the bullets of higher velocity ammunition leave the barrel when the muzzle is at a much lower point in the curve of vibration and therefore shoot low at 200 yards, but their trajectory being flatter than the 2,000 ft./sec. ammunition, crosses the path of the latter at at 390 yards and keeps above it at all later ranges.
(Brian Labudda & Ian Skennerton in Accurizing & Shooting Lee-Enfields, 2005.)

The context is in the observations and mythology of the "full-bore" rifle clubs in Australia which went back to the .303 Martini-Henry, Lee Metford and "Long Tom" magazine Lee-Enfield days (indeed, those were all the clubs ever had until about 1934). I mean nothing derisory by "mythology" - more memorable than facts and less mutable, I always say. Sufficient to say the observations are based on countless thousands and thousands of carefully fired and often individually recorded shots over four generations or more of club shooting at all distances out to 1,000 yards.

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