Multigunner
08-17-2015, 10:10 AM
Ran across this years ago but didn't give it much thought at the time.
Idea of SMG cartridge was born presumably in late 1920s, but there were some problems, created by the reduced powder space of strengthened cases. A new kind of powder was needed to allow loading with heavier compressed-load charges without exceeding the maximum limit of chamber pressure. The new propellant was presumably VihtaVuori's N 13 (from 1st September 1973 known as N 330. Still in production, and called - inofficially - as "the submachine gun powder"). I don't know, whether the bullets with a weight 8.0 grams were actually adopted. I have met just those with weight 7.5 grams from the war-time loads. There was a severe shortage of copper and lead in Finland during the war-time in 1939 - 45. Half gram of "strategic materials" per bullet means a ton of them when 2 millions of bullets are produced. A daily consumption during the most ardent phases of wars, when life or extinction of Finnish people was at stake.
Not for frail pistols!
Volume of the powder gas, generated by increased charges of "submachine gun powder" burning by the Mendeleyev's principle developed a long-lasting remaining pressure into the bore of submachine gun, where it was beneficial, but also into the pistol bore, where it might be harmful. Some pistols with a short recoil mechanism are designed to shoot loads generating just a low remaining pressure when the breech-bolt starts it's independent movement backwards after "unbolting". Best known example is Mauser C-96 (photo at right): Remaining pressure blows the breech-block back and completes the reloading cycle. Some other handguns, like Luger/Parabellum P-08 and Lahti L-35 (= in your country, Sweden, Husqvarna Model 1940) needs no remaining pressure at all for functioning of action.
Shooting with SMG cartridges could sometimes wreck Parabellum pistol by first shot, and many L-35 pistols in collections have a fracture on their "Achillean heel", below the fulcrum of accelerator lever, on the left side of receiver, behind the barrel. Pistol L-35 without this fracture has presumably never been "Over There" (= in the actual battle). At least it has been never "discharged in anger". Fourth kind of 9 x 19 mm pistols, issued to Finnish Air Force personnel, was omivorous: Safe to shoot with SMG cartridges. It was Browning Hi-Power or F.N. GP-35 with a refined Browning mechanism of action (light barrel and heavy slide, connected with ribs during the high pressure
I may have fired a few rounds of this ammo, or a similar SMG specific cartridge in a P-35 back in the early 70's.
I had picked up a handful of loose rounds dirt cheap at a gun shop. Their was no packaging but the rounds looked okay, old but clean enough.
The rounds I tried out had truncated cone FMJ cupro-nickel bullets. The primers were very hard, requiring two or three strikes from the light pistol hammer fall to ignite.
When the rounds finally fired there was very noticable recoil, felt recoil with standard 9X19 loads was not noticable with the Browning's wide grip.
I was firing into a muddy ditch and where the bullets struck they made a very large hole, like a large shovel full of mud had been dug out. Power level was much like a hot .357 Magnum load. Muzzle blast was impressive.
After three shots I decided these were likely to damage my pistol so I chucked the remaining few rounds in the ocean.
I've also read of a German SMG load that used slow powder and a 130 grain iron core bullet. Someone chrono'ed some of these at 1600 FPS from an MP40 barrel.
I've been told that Israel also loaded some similar 9X19 ammo for use in the Stengun, and Italy loaded a very hot 9mm cartridge for the Berretta SMGs that the Germans prefered for SMG use when they could get it. Its unlikely that much if any of this sort of ammo is still around but you never can tell.
This site
http://guns.connect.fi/gow/QA7.html
Has a lot of info on Finnland's WW2 weaponry.
Idea of SMG cartridge was born presumably in late 1920s, but there were some problems, created by the reduced powder space of strengthened cases. A new kind of powder was needed to allow loading with heavier compressed-load charges without exceeding the maximum limit of chamber pressure. The new propellant was presumably VihtaVuori's N 13 (from 1st September 1973 known as N 330. Still in production, and called - inofficially - as "the submachine gun powder"). I don't know, whether the bullets with a weight 8.0 grams were actually adopted. I have met just those with weight 7.5 grams from the war-time loads. There was a severe shortage of copper and lead in Finland during the war-time in 1939 - 45. Half gram of "strategic materials" per bullet means a ton of them when 2 millions of bullets are produced. A daily consumption during the most ardent phases of wars, when life or extinction of Finnish people was at stake.
Not for frail pistols!
Volume of the powder gas, generated by increased charges of "submachine gun powder" burning by the Mendeleyev's principle developed a long-lasting remaining pressure into the bore of submachine gun, where it was beneficial, but also into the pistol bore, where it might be harmful. Some pistols with a short recoil mechanism are designed to shoot loads generating just a low remaining pressure when the breech-bolt starts it's independent movement backwards after "unbolting". Best known example is Mauser C-96 (photo at right): Remaining pressure blows the breech-block back and completes the reloading cycle. Some other handguns, like Luger/Parabellum P-08 and Lahti L-35 (= in your country, Sweden, Husqvarna Model 1940) needs no remaining pressure at all for functioning of action.
Shooting with SMG cartridges could sometimes wreck Parabellum pistol by first shot, and many L-35 pistols in collections have a fracture on their "Achillean heel", below the fulcrum of accelerator lever, on the left side of receiver, behind the barrel. Pistol L-35 without this fracture has presumably never been "Over There" (= in the actual battle). At least it has been never "discharged in anger". Fourth kind of 9 x 19 mm pistols, issued to Finnish Air Force personnel, was omivorous: Safe to shoot with SMG cartridges. It was Browning Hi-Power or F.N. GP-35 with a refined Browning mechanism of action (light barrel and heavy slide, connected with ribs during the high pressure
I may have fired a few rounds of this ammo, or a similar SMG specific cartridge in a P-35 back in the early 70's.
I had picked up a handful of loose rounds dirt cheap at a gun shop. Their was no packaging but the rounds looked okay, old but clean enough.
The rounds I tried out had truncated cone FMJ cupro-nickel bullets. The primers were very hard, requiring two or three strikes from the light pistol hammer fall to ignite.
When the rounds finally fired there was very noticable recoil, felt recoil with standard 9X19 loads was not noticable with the Browning's wide grip.
I was firing into a muddy ditch and where the bullets struck they made a very large hole, like a large shovel full of mud had been dug out. Power level was much like a hot .357 Magnum load. Muzzle blast was impressive.
After three shots I decided these were likely to damage my pistol so I chucked the remaining few rounds in the ocean.
I've also read of a German SMG load that used slow powder and a 130 grain iron core bullet. Someone chrono'ed some of these at 1600 FPS from an MP40 barrel.
I've been told that Israel also loaded some similar 9X19 ammo for use in the Stengun, and Italy loaded a very hot 9mm cartridge for the Berretta SMGs that the Germans prefered for SMG use when they could get it. Its unlikely that much if any of this sort of ammo is still around but you never can tell.
This site
http://guns.connect.fi/gow/QA7.html
Has a lot of info on Finnland's WW2 weaponry.