If you are interested, barrel life with steeljacketed projectiles, copper or gilding-metal plated, runs approximately 60% of that when softer alloy jackets are used. Unplated steeljacketed bullets cut barrel life 50%. This when fired in standard barrels with Mauser or Enfield type sharp-land and sharp-groove rifling; with segmental rifling or with radius-groove type, barrel life can be prolonged perhaps 15% to 20%.
On tracers:
Color of the trace may be green, yellow, white, red, or a combination, green changing to red as the composition burns in flight.
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German tracers were the best put out by any country; ballistics were excellent and the white and yellow colors were perfectly visible in the bright desert sunshine against buff-colored sand dunes as a background.
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One explanation for the variety of tracer colors was that for night use it was possible to identify particular guns, and to signal with them and otherwise improvise special communications in the field according to locally prearranged plans. This was done quite a bit in Italy, German scouts pinpointing Allied points with long-range tracer crossfire from either rifle or machine gun.
On the 9-mm cartridge:
The standard loading for the regular cartridge called for a 124-grain bullet at approximately 1,050 FPS out of the short-barreled M’08 pistol. It is known throughout the world as the Parabellum cartridge.
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The German ‘08 alternate cartridge appeared in the field in 1941 in small quantities, but within two years was the only type in production. This is the “black” cartridge, officially the “M’08 mit Eisenkern,” or “with iron core.” The case is steel; bullet is steel-jacketed, with mild steel core; the jacket is plated with copper inside and out, and the entire bullet and case are blackened for identification and rustproofing. The bullet weighs only 98-grains and has a heavier propelling charge than the standard load, but contrary to previous reports, this cartridge is perfectly safe to use in any 9mm caliber ‘08 pistol in good condition. I have shot hundreds of them through Lugers and Walthers. Velocity is quite high—I do not know the exact figures, but breech pressures are no higher than in the standard loading, due to the light bullet. The cartridge was intended primarily for the machine pistols, or submachine guns and does not give particularly good results in handguns, but is not dangerous.
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Winchester loaded some 9mm Luger ammunition during the war, using 115-grain bullets. This was the finest ammunition we could locate in early 1943, and the only kind equal to the older (prewar) German stuff.
On the Italians:
The Italians went off the deep end on ordnance. Apparently anybody’s brother-in-law could sell his pet caliber or model or modification. And as previously stated, they never got rid of anything. It might die a natural death, but as long as it was not actually broken, it stayed in service even if it was the only one of its kind. Anything collected in a war was kept for use in that and all future wars, regardless of whether or not it was worth keeping, using or supplying.
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Undoubtedly some of the confusion in velocity figures on Italian ammunition is due to their nonchalant use of any propellant handy at the time they were loading a batch. I broke down many cartridges, and sometimes found different components in the same rifle clip.
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Ballistically it was OK; the long bullet had good range, was accurate enough, gave great penetration, but had failed to stop angry Africans.
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Two different 8mm rimmed cartridges were loaded by Italy. One was the old 8mm Mannlicher, formerly the Austrian service cartridge, called by the Germans the 8mm Austrian M93 cartridge, Ogival; Italy collected quite a few Austrian rifles and machine guns as her part of the loot in the World War I settlement, and decided to use them till they fell apart.
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From Italian ammunition we can go to Italian weapons. Rifles: Lots of them, all different in some respect or other; to cover their endless modifications would take a bigger book than this can be and there are only about a dozen true models.
I think you would really appreciate this interview.
The Interview: L. James Sullivan Part I(three parts)
http://smallarmsoftheworld.com/display.article.cfm?idarticles=110
He worked on a lot of guns including the M-16.
Good interview, a little bit of history from a guy with an interesting perspective.