From: Riverview ,Florida
The first weapon available to the infantry to have a limited effect against armor is the machine gun. Machine guns derive their limited armor-penetrating capability both from the single bullet's penetration ability and from the effect the repeated hits of bullets in quick succession - as is the case with a machine gun - onto the same spot have on thin steel plates. The metal's structural integrity suffers and eventually tends to break from material fatigue. Therefore, to judge the penetrating power of machine guns the determining factors are:
•penetrating power of the ammunition used (depending on the V0 the weapon achieves with the ammunition),
•theoretical and practical rate of fire and
•accuracy / density of the hit group
(the hits need to be concentrated on a small area to achieve the effect described above).
Infanteriepatrone 7,9mm / Mauser 7.92x57 amunition
This cartridge was used by the german Mauser Karabiner 98K, Gewehr 41, 43 and numerous other rifles as well as in aircraft, vehicle and infantry machine guns. As the german standard rifle cartridge it was called Infanteriepatrone 7,9mm ("infantry cartridge"), also known as the 7,9mm - Militärpatrone ("military cartridge") or as Mauser - Standardmunition 7,92x 57 (Mauser as the weapon company that introduced the ammo for its famous 98K rifle; 7.92mm is the calibre and 57mm the length of the casing (not the chamber as in the US); also, in germany a bore's caliber is measured from land to land). The total production of this cartridge during WW II was 10,475 million (that is over ten billion). Sometimes, esp. among angloamericans, it is also referred to as 8 mm Mauser.
The fired projectile of the Infanteriepatrone had a typical initial energy E0 of 3,700 Joule (sS - projectile of 12.8g at a V0 of 760m/s) but could reach initial energies of over 4,500 Joule (some V-Patronen) depending on the concrete ammunition type and firing weapon.
Between 80 and 90 % of all 7,9mm ammunition produced was of the 7,9 sS (sS for schweres Spitzgeschoss = "heavy pointed bullet") type; the complete cartridge weighed 27g, it was 80.6 mm long and contained 2.7g of gunpowder; the projectile weighed 12.8 g and was 35mm long. When fired from a MG34 or MG42 (as well as from the other rifles using the cartridge) it had a typical V0 of 755 m/s. The regular sS projectile had the following penetration performance: 85cm of dry pine wood at 100m, 65cm at 400m, 45cm at 800m and 10cm at 1,800m; 10mm of iron at 300m, 7mm at 550m; 5mm of steel at 100m; 3mm at 600m.
The second most used type was the SmK (Spitzgeschoss mit Kern = "pointed bullet with core") bullet that measured 37.2mm, weighed 11.5 g and contained a hardened steel core (about 8% of all produced 7.9mm rounds).
Another type was the SmK L'spur (L'spur = Leuchtspur = "bright trace" = "tracer") bullet that was the previous type combined with a tracer that burned for 800 to 900 m (a little less numerous than the SmK). In the picture at right a soldier is seen preparing a 7.92mm ammunition belt for a machine gun (presumably adding tracers at every seventh round).
The lS (leichtes Spitzgeschoss = "light pointed bullet") which had an aluminum core and therefore weighed only 5.5g which resulted in a higher speed of V0 = 925 m/s but of course also in a shortened total range (the bullet was used mainly in the air defense role; about 4-7% of the total production), the lS-L'Spur which with a length of 37.2mm and a weight of 6.1g was again the tracer version of the lS (less than 1% of total production).
A version produced mainly for use with the MG 17 as aircraft armament was the so-called V-Patrone which had an increased powder charge that increased the V0 by 15%. This ammunition type was available with the PmK projectile ("Phosphor mit Stahlkern" = "phosphor with steel core") or with the B ("Beobachtung" = "Observation") projectile contained a little phosphor and exploded upon impact, the latter ammunition type was also known as the B-Patrone and was used as an incendiary round; both types are not counted in the 7,9mm production
The final and most interesting (for our purposes) bullet type was the SmK(H). The H stood for Hartkern (hardened core), this was the armor piercing version of the 7,9mm Infanteriepatrone. The projectile had a length of only 28.2mm, weighed 12.5 g and contained a tungsten core that was 22.5 mm long. The propellant gunpowder of the shell was increased to 3.6 g. The bullet had a penetration power of almost 20mm of plain steel at a range of 500m (90° impact angle). However, production of this ammunition type ceased in March 1942 because of an acute shortage of tungsten; still, SmK(H) cartridges continued to be issued to the troops as late as February 1943. while it was still inproduction, this ammo type accounted for 1 to 2 % of the production of 7,9mm Infanteriepatronen.
When the machine guns used the normal sS ammunition they achieved an armor penetration of up to 10mm and more at close ranges. Now, on to the machine guns themselves. Development of the german machine guns went towards a general purpose machine gun, therewith abandoning the differentiation hitherto between light machine guns carried around by the assaulting infantry and heavy machine guns that were intended as stationary support weapons. First developments in this direction were the MG 29 and the MG 30. The latter was not accepted by the german armed forces but by the austrian army; therefore, after austria became part of the third reich, the Wehrmacht eventually had this weapon too. It was also produced during WW II in a small production run for the finnish forces. Another development by the companies Mauser and Metallwarenfabrik Kreuzlingen led to the LMG 32 that formed the basis for the MG 34.Wondered that myself,and pulled this from the internet.
< Message edited by Dane49 -- 6/26/2012 5:19:28 PM >