-3VBM19: The 3VBM19 is in every way, an improvement of the 3VBM17 due to using improved penetrator design and sabot (3BM42M and 3BM44M respectively for the 3VBM19 VS the 3BM42 and 3BM44 for the VBM17). The penetrator is made out of Tungsten.
-3VBM21: The 3VBM21 is a new design that uses the 3BM46 penetrator and the 3BM48 "Svinets" sabot.
-3VBM23: The 3VBM23 is an APFSDS that uses the 3BM46 penetrator but with an improved sabot (3BM48 "Svinets-2"). The improved sabot increases both muzzle velocity and energy conservation of the 3BM46 penetrator. The penetrator is made out of Depleted Uranium.
Hopefully that satisfies your curiousity.
Thanks for your explanation. However I was curious because Russian two-piece APFSDS rounds are inherently inferior to western single-piece counterparts due to their limitation of penetrator length which cannot be elongated more than the point where the penetrator meets the propellant. Then how could they improve their penetration to more than M829A3, the most modern US DU APFSDS which is said to have 700~800mm penetration, by just tweaking the sabot?
I don't know where you heard that fairytale, but it's wrong. The problem was rather in the limitation due to the lenght of the rounds the autoloader could accept.
Here's a chart I found, it may not be 100% accurate, but it's enough to give one an idea about armor and armor-penetration performance.
Last edited by Hyde; 04-15-2012 at 01:09 PM.
Atleast the T-90S Bhishma cant fire the newer rounds due to limits imposed by its older autoloader
Here are some more technical details on 3BM42 rounds from a RFI floated by Indian MOD , they are ordering 66,000 3BM42 and 25,000 for Invar . The 3BM42 goes by designation AMK 339 by MOD
Caliber. The ammunition should be capable of being fired from 125 mm Smooth Bore Tank Gun of T-90 and T-72 tks.
Shelf Life Not less than 15 (fifteen) years under Indian Tropical Conditions. Specification with regard to explosives fillings with test procedures to evaluate the shelf life be made available to DGQA (Indian QA Agency). Literature substantiating the claim that explosive fillings would give stipulated shelf life need to be made available.
4. The major technical characteristics are as under:-
(a) Round Designation of Mark - 3BbM17
(b) Projectile Designation or Mark- 3bM-42
(c) Mass of Shell or Shot (kg) - 7.05 kg
(d) Mass of Round (kg) - 20.4 kg
(e) Primer - GUV-7
(f) Designation of SCC - 4>K 63
(g) Increment Propelling charge - 9.50 kg
(h) Muzzle Velocity (m/s) - 1700
(j) Effective Range (M) - Not less than 2700
(k) Consistency group of Rds - HSD & VSD ≤ 0.35 mil
(l) Tracer - 3YPZM
(m) Armour Piercing Characteristic. The depth of perforation (piercing) in mm.
Prospective vendors to state details.
(n) Nominal Pressure - 440 M Pa
(o) Maximum Pressure - 530 M Pa
Just as with the number of pieces, you assume the wrong thing, the absolute lenght isn't proportional to the performance. Not saying it doesn't have an effect, it obviously does, but you can not directly deduce the penetration capabilites from the lenght of the sabot alone, the gun and propellant also play a part, and are which gives the round the energy in the first place. If it was the other way around, a "western" round which is shorter achieving the same penetration as a Russian round which is longer, you would take it for granted and attribute it to some imaginary superiority and sophistication in "Western" engineering.
If the round in question is longer and requires the new autoloader and is supposed to be used by T-90A or T-90MS and above, maybe the penetration figures were achieved using another gun, namely the newest 2A46M-5 or 2A82.
I'm not saying that Russian technology is primitive. I'm a rather Russian weaponry admirer. I just thought that Russia might be quite more advanced in such areas like material engineering/metallurgy than the United States if they could achieve same penetration with some 60mm shorter penetrator as the lengthening the penetrator without breaking the balance of overall ballistic performance is the most critical factor for the penetration anyway, and Russian 125mm guns like 2A46M-5 has somewhat less chamber pressure compared to western Rheinmetall 120mm(at least I heard so. If not, please enlighten me).
Regardless, thank you all for the infomations.