1941 Winchester .303

[togor]

Well my shooting bolt head is assembled, ammunition ready. Just need a bit of time and decent weather.

NOS bolt head assembly is.... interesting but uneventful.

[Bindi2]

Cordite seems like a bad idea in hindsight but at the time it was the next step in evolution of propellants.
BP, guncotton for artillery, cordite for small arms, nitro cellulose.
Being a target shooter from the Cordite days to a NC target shooter today i don't see any difference in the erosion of barrels.
The primers used today are far away much more user friendly. The saying cleanliness is next to godliness is not true anymore. Corrosion is not the problem.
What i do see is the waste of barrels because of the use of closed base projectiles when open base projectiles will continue to be accurate.

[togor]

Found this. No doubt some of you knew this fellow.

History of the .303 British Calibre Service Ammunition Round

Short service history with BP before Cordite comes along, but Nitrocellulose is right there too. Given reason per the history was Cordite being superior in warmer climates (Empire business)

Real reason would look to be more about having a home grown solution, regardless of other considerations.

History of Cordite Production

[Alan de Enfield]

Found this. No doubt some of you knew this fellow.

History of the .303 British Calibre Service Ammunition Round

Short service history with BP before Cordite comes along, but Nitrocellulose is right there too. Given reason per the history was Cordite being superior in warmer climates (Empire business)

Real reason would look to be more about having a home grown solution, regardless of other considerations.

History of Cordite Production

Having looked at the propellant, you may find the history of the bullet itself of interest ;

It does go into some detail about wound profiles of various 'Mk' of the 303.

Warning graphic descriptions[/B]

Example :

Major Mathias, RAMC, who inspected the battlefield after Omdurman, observed a young man, who had been struck twice by a Mark IV bullet,
He had a bullet wound of the left leg above the knee. The wound entrance was clean-cut and very small. The projectile had struck the femur, just above the internal condyle; the whole of the lower end of this bone, and upper end of the tibi, were shattered to pieces, the knee joint being completely disorganised.
He had also been wounded in the right shoulder...The whole of the shoulder joint and scapular were shattered to pieces. In neither case was there any sign of a wound of exit.

[togor]

Open base, flat base projectiles hard to come by for this caliber. Why I stocked up a bit on this WW2 Winchester ammo, for the "missiles".

[scharfschutzen63]

I'm so happy I don't live in the UK. With our new President, things have been getting better here every day. Hallelujah!

[togor]

Who can't enjoy a US President with an inability tell ally from an enemy? Fun for the whole family!

Back to bullets...yes the original "Dum Dum".
It's ban being the one meaningful development out of the various disarmament conferences so popular before the Great War. Also why shot placement is so important in ethical hunting.

M-16s earned a bad reputation when they entered Vietnam service but that FMJ 55 gr. bullet left severe wounds from fragmenting at impact. The SS109 projectile was invented to better penetrate Soviet winter uniforms, but a sturdier bullet imparted less grievous wounds.

[Strangely Brown]

The SS109 projectile was invented to better penetrate Soviet winter uniforms, but a sturdier bullet imparted less grievous wounds.

Shades of producing the No.4 spike bayonet to better penetrate Chinese troops winter clothing.

[Bruce_in_Oz]

Not too sure about the "winter uniform" penetration bit. It take a LOT of cotton fabric and goose feathers to stop a bullet, even a pistol-calibre one. I recall that some lads set up cardboard "figures" swathed in half a welfare-store's worth of clothing and with blocks of Ballistic gel behind, to test this story. M-1 Carbine bullets fired at reasonable close-quarter battle ranges, flew through the frocks and drilled deeply into the Gel..

That the soviets were steadily introducing body armour on an expanding scale by the late 1960s was well known.

"SS109" is a composite cored bullet, not unlike a scaled-down .303 Mk7, but with a boat-tail.

The earlier M-193 55gn BTFMJ was designed back i the late 1950s. From a the original 1:14" twist barrels it performed well on "tissue". It would perform a 180 degree turn after striking "muscle tissues" and internal organs and sometimes continue to exit base-first. However, it appears to have been a little "unstable" in flight at Arctic-grade temperatures, so the rifling was adjusted to 1:12" twist. . "Field" results revealed a change in terminal performance; the "more stable' bullet apparently took a little longer to "tumble" in tissue, often drilling all the way through before starting to go wayward.. Sometimes, however, the M-192 bullet would break in two, with both fragments charting completely different courses.

SS109 was derived from a LOT of experiments with "heavier" (up to 77grain) bullets for extended range performance. This was primarily aimed at the new "Light Support Weapon" market.

SS109 and its "clones" will happily stabilize from a 20 inch barrel with a 1:10" twist. So, why the 1:7" twist as "NATO Standard"?


TRACER bullets. to obtain a useful "burn time" fir a tracer bullet in a bullet of such dinky diameter, tha answer was a LONGER bullet. This needed a 1:7" twist to stabilize it.. See also dinky short barrels which produce lower velocoies and thus LOWER spin-rates

At the rotational velocities of the SS109 / M855, etc bullet, terminal ballistics get "interesting". Shortly after impact, the bullet starts to tumble as it transits into a denser medium. The two-piece core can be "disrupted" and the bullet breaks into several separate "fragments. Supplementary, at short-ish ranges, the bullet will still be precessing (wobbling around the nominal trajectory) after it has just left the muzzle. Thus, it will be less-than-perfectly stabilized. We have been down this stability discussion route a few times in the last few years..

One of the reasons for the initial instability is that SS109, like .303Mk 7, is BASE HEAVY.

The old "wisdom" of .303 being "humane" and drilling neat holes is only partly true, and then, only in some circumstances..

If said bullet slips through a light-weight uniform and a few inches of muscle tissue, so far so good.

If the next order of business is striking a material like BONE, things change, rapidly. Think "thigh wounds"; big, meaty target, with a big BONE in the middles. A bullet striking that femur WILL shatter it. Two things:

When that bone is violently broken, the leg ceases to be a "strut", holding up half of the body's weight.two ends of sharp, fractured bone start "wandering about" . Adjacent to said damaged bone is the famous Femoral Artery.. Get a hole in that and you are in serious trouble. Holes may be generated by the slicing action of the shattered bone ends or by "secondary missiles", blasted off the parent bone by the bullet impact.

"Only a flesh wound"? It ain't like he movies .Ask your friendly First-Aid instructor about putting an improvised tourniquet on a "leaking", upper thigh wound.

[Bruce_in_Oz]

SS109 bullets will drill through soft tissue MOSTLY without much distrbance.

Ditto the classic .3.3Mk VII.

Hitting anything more robust on the way in or through, changes the game, someshat.



The old M-193 55 gn bullet astabilize OK in the original 1:14" twist M-16.
Sub -optimal stability at sub-zero (C) temperatures (denser air) messed that up. Hence the 1:12" twist..

M-193 causes soft tissue damage partly due to the hydrostatic shock of its velocity on impact. It WILL "tumble" and MAYBE break in two after impact, in a sufficient muscle mass.. Hitting anything harder (bone) on the way through? Instant destabilization with wildly variable results.

Note that the bullet for the Russian 5.45 x 39 7N6 is base heavy and composite cored, just like the SS109 / M855. Funny, that!

The Mk Vll .303 was a masterpiece of "political" bullet engineering. It met he "rules in "form",but the characteristic "tumbling" / bending AFTER impact was a result of careful research into the behaviour of "base-heavy" bullets in live tissue. It was also partially accidental: The initial "spitzer" bullet was about 20 grains lighter and somewhat shorter. The Brits needed a spitzer bullet that would run reliably in a zillion Lee Enfields, so, it had to be a certain overall length, which also helped int the peculiar way the ammo was made (Another story),Hence the "lightweight 'nose filler" that achieved the desired muzzle velocity from the "short" rifle and "by accident" both met the "rules of the game" and produced "interesting" terminal ballistics.