sabot rounds on 7TP

[cbo]

IIRC "sabot" is sometimes used to represent rounds with very limited performance like the AP used in the French 37mm tank gun. Something about the performance of normal AP dropping off in a liniear fashion with range while sabot drops faster with range and thus is a better representation of a weak low velociy AP round that penetrates something at short range but not much at, say 500 meters.

Dont know if that is the reason?

The Germans were the first to use "sabot" in combat in the form of APCR in 1940, but experiments had been going on since the 1920ies, first with Gerlichs taper-bore hunting rifles, then with a cooperation between Larsen in Denmark, where Gerlich worked, and the French resulting in subcaliber rounds for the French 25mm anti-tank. Still experimental in 1940 and not issued, but IIRC the French shipped all their research to Britain and the US. Janacek in Czechslovakia also did some work on taper-bore guns, resulting in the Littlejohn adapter for the British 2-pdr later in the war. Don't know if the Poles ever worked on something similar, but they did experiment with some very powerfull rounds for their anti-tank rifles - IIRC they were full-caliber, though.

[Mobhack]

Originally Posted by cbo

IIRC "sabot" is sometimes used to represent rounds with very limited performance like the AP used in the French 37mm tank gun. Something about the performance of normal AP dropping off in a liniear fashion with range while sabot drops faster with range and thus is a better representation of a weak low velociy AP round that penetrates something at short range but not much at, say 500 meters.

Dont know if that is the reason?

The Germans were the first to use "sabot" in combat in the form of APCR in 1940, but experiments had been going on since the 1920ies, first with Gerlichs taper-bore hunting rifles, then with a cooperation between Larsen in Denmark, where Gerlich worked, and the French resulting in subcaliber rounds for the French 25mm anti-tank. Still experimental in 1940 and not issued, but IIRC the French shipped all their research to Britain and the US. Janacek in Czechslovakia also did some work on taper-bore guns, resulting in the Littlejohn adapter for the British 2-pdr later in the war. Don't know if the Poles ever worked on something similar, but they did experiment with some very powerfull rounds for their anti-tank rifles - IIRC they were full-caliber, though.

A sabot round in WW2 is usually an APCR. Its book muzzle AP value is higher than the plain shot, but the sabot range is less than the plain shot's so the pull-down for range will happen faster. Later better-designed APCR ammo can have a longer sabot range, but it still will be less than the AP range due to the "shuttlecock" effect of firing a full bore round with a "skirt" of lightweight metal that slows it down faster.

With APDS the opposite will be true. APDS drops the sabot rather than carrying it (and its wind resistance acting on a lighter shell) all the way to the target.

However a sabot round can cover other AP ammo, usually of a greater muzzle penetration than the regular round. However the French 37 shortie was a special case where the HE range was average, but a "sabot" round of limited range C/F the HE range was used to cover the poorly performing AP without slugging its primary role of putting out little HE shells. otherwise either the HE range would have had to be abysmal, or the AP round would over-perform due to its matching the main gun range (which is used for AP and HE).

Sabot ammo uses the sabot AP value, and the sabot range is used to determine the pull-down factor for range.

AP, HEAT and HE use the regular gun range, and for AP it is that range that is used for the pull-down factor.

SP 101 as explained in the Mobhack help, the effects can of course be seen by running APCalc for various weapons.

Andy

[PvtJoker]

Just a little comment on the French 37mm L21 gun (SA18):

The round you have modeled as sabot (AP Pen 3) was in fact one of the first service APCR rounds for tank guns. The original AP round for that gun was a naval design dated to the 1800s (basically a simple steel shot) and had a much lower penetration, something like 10-15 mm at 100 meters (90 degrees).

Many countries which purchased the FT-17 after WW1 did not get the improved French ammo. Finnish tests of the original AP ammo showed that it was incapable of penetrating 10 mm armor quality plate at 100 meters and was therefore nearly useless even against lightly armored vehicles. The French seem to have realized that some time in the 1930s and went for the best possible AP round they could design for that gun, since they had it on so many of their light tanks. Muzzle velocity was 600 m/s, which was pretty impressive for that gun.