Guardsmen in the Fall, Part 3: Battle at Vasilievka

"3. Battle at Vasilievka

The situation on the morning of September 27th was as follows:

• 9th CD defending at Kozelnoye and further to north-east.
• 5th CD defending at Horol and Zaparidovshina
• Left and right flanks of the divisions were open
• 6th Guards ITB at height 191.2 and Pomerki

The brigade's orders were to cover Vasilievka from the side of Kozelnoye. Against the 9th CD, up to regiment of infantry and 20 enemy tanks were sent. From 20 km south-west of Zaparidovshina, more enemy tanks approached. 

On September 26th, the enemy showed activity, and occupied Horol (on the right flank of the 5th CD). The 6th Guards ITB was moved to Pomerki, covering an open approach. 

At 8:00 on September 27th, the enemy attacked. A column of 60-65 tanks with infantry support appeared in the south, aimed at the open left flank of the 5th CD. Upon reaching the Zaparidovshina-Kapustnitsa road, the split up. One part of the force went to Kozelnoye, the other to Kapustnitsa and Vasilievka. 

At 9:00, the 6th Guards ITB received an order to dispatch a company of T-34s in order to prevent the enemy from reaching Kapustnitsa. The enemy reached Kapustnitsa first, set the village on fire, and moved to Grun. 

The tank group that was moving to Kozelnoye was flanked by the elements of the brigade at Pomerki and height 191.2. 

Acting on their own initiative, a group of tanks from the brigade left for Vasilievka. Despite numeric advantage, the enemy did not withstand the attack, and fled in the direction of Kapustnitsa. 

Heights 181.4, 191.2, and Vasilievka were held by the brigade all day, and half of the night, after which, as ordered, they left for Grun. During that day, the enemy lost:

• Tanks: 8
• Vehicles: 40
• Infantry: 50

The brigade lost:

• T-34 tanks: 1
• Armoured cars: 1
• AA guns: 3
• Fuel trucks: 1
• Engineering vehicles: 1
• Killed: 5
• Wounded: 6"

Previous in series: Battle at Semenovka
Next in series: Battle at Mtenovka

Guardsmen in the Fall, Part 2: Battle at Semenovka

"2. Battle for Semenovka

On the morning of September 23rd, elements of the 6th Guards ITB, retreating to Lipovka, concentrated as follows:

• Company of T-40 tanks: at Semenovka
• Remainder of the brigade: at Tolotyh
• 5th CD at Kimlichka and south

The 6th Guards ITB, leaving behind a reserve and its commander, was to reach the Mihailovka region by morning of September 24th. 

The enemy, taking advantage of the retreating divisions, entered Semenovka.

Based on the orders by the commander of the 5th CD Major-general comrade Baranov, the brigade received an order: to knock the enemy out of Semenovka, and hold until elements of the 5th CD reinforce them.

Elements of the brigade attacked at 16:00, flanking Semenovka from the south, and took the village. Despite the advantage in numbers and firepower, the enemy left Semenovka, moving to the west, taking heavy losses. After pulling up reserves, the enemy started circling Semenovka from the left, forcing elements of the brigade to retreat. After darkness, the brigade was ordered to leave the battle and join the Tolstyh brigade. The brigade retreated, covered by two KV tanks. As a result of the battle, the enemy lost:

• Guns: 7
• Mortars: 7
• Infantry: one company

Losses of the brigade:

• T-40 tanks: 4
• Killed: 8
• Wounded: 19
• Missing: 5"

Previous in series: Battle at Lipovka
Next in series: Battle at Vasilievka

Guardsmen in the Fall, Part 1: Battle at Lipovka

Everyone has heard of the T-34, the KV, the IS, the Tiger, the Panther. These tanks are some of the most iconic vehicles ever built. However, many lesser known, but nonetheless important, vehicles also entered the field of battle.

One of these vehicles was the T-40. A meek amphibious scout tank, it did not receive a real cannon, just a DShK heavy machine gun. Even in this role, it was soon replaced by the cheaper and better armed T-60, and later T-70. However, these small tanks managed to fight fiercely throughout WWII. This series of articles covers seven battles with these tanks in the 6th Guards Tank Brigade (then 1st Tank Brigade). The quality of both the typewriter and the scan is not so great, so a number of the village names might be incorrect.

1st Tank Brigade, receiving new T-40 tanks

"A short report on the actions of the 6th Guards Tank Brigade from September 17th, 1941 to February 20th, 1942.

1. Battle at Lipovka

On September 18th, 1941, we finished offloading at the railroad station Akhtyrka. The brigade was deployed to a new region, and, by 7:00 on September 21st, concentrated in the vicinity of Dvisvka and Reznikov (20 km south-east of Romny). 

Overall situation on September 21st: the enemy directed Guderian's second group towards Romny, occupying Hmelev (37th Tank Division), Romny (10th Motorized Division), and Lohvitsa (3rd Tank Division). Additionally, the SS division "Reich" was present, consisting of four infantry regiments reinforced with tanks. 

Our forces consisted of Major-General Vylov's 5th and 9th cavalry divisions, 6th Guards Independent Tank Brigade, 129th Independent Tank Brigade, 1st Guards Independent Division, defending:

• 9th CD: Pravduki, Pogonaya Prinytsa
• 5th CD: with a company of T-34s of the 6th Guards ITB, Pogonaya Prinitsa, Perekrestovo, Bobrik.
• 129th ITB: heavily undermanned, east of the 9th ID, with HQ at Nedrigailov
• 6th Guards ITB: Reznikov, Lipovka
• 1st Guards ID: Nedrigailov 
• The 227th ID defended 20 km north-east of Nedrigailov

The enemy had an encircling position, especially on the left flank, which was threatened by the 3rd Tank Division and SS division "Reich". Subsequent actions show that the enemy was planning to attack from Romny, to the east, and paralyze the main forces of the mechanized group, and then strike with the 3rd Tank Division and "Reich" division from south-west, cut off the retreat at river Horon, and destroy the group.

On September 21st, the 6th Guards ITB, missing a company of T-34s, was ordered to, remaining in the region of Reznikov and Lipovka, block the approach of the enemy from the south, flank, and rear of the 5th CD. After the 5th CD is replaced by elements of the 1st Guards ID, retreat together to the Semenovka region.

The brigade took defensive positions. A company of T-40 tanks fortified west and south of Reznikov. 1st Tank Regiment sent a company of medium tanks and a company of heavy tanks to the south of Lipovka, facing south, and two companies of T-40 tanks, facing west. 

At 10:30, on September 22nd, elements of the SS division "Reich" advanced in the direction of Dolgaya Luka to Lipovka. The advance was supported by mortar fire, 105 mm howitzer fire, and a company of tanks.

At 700-800 meters, the heavy and medium tanks opened fire. After taking heavy casualties, the infantry was suppressed, and their tanks retreated. Taking advantage of the enemy's inaction, the 1st Tank Battalion of the 1st Tank Regiment counterattacked, reaching the forest north of Dolgaya Luka, destroying with fire and tracks enemy infantry and armament. The tanks returned to their rendezvous point. 

Despite their losses, the enemy brought in reserves and resumed their attack. The attack was not successful. A motorized infantry company was assigned to clear out the enemy, joined by a battalion of the 1st Guards Infantry Division. 

The battle lasted all day. 5th and 9th Cavalry Divisions retreated to the east, to a new defensive line. In this battle, the enemy widely used snipers and "cuckoo birds" [Note: slang for snipers in trees"]. After the main enemy elements retreated, the "cuckoo birds" would remain, firing at commanders.

Elements of the brigade, during the day, executed 7 attacks, as a result of which, the enemy was defeated, and scattered. Enemy losses include:

• AT guns: 13
• 105 mm howitzers: 4
• Mortars: 7
• Motorcycles: 16
• Fuel trucks: 2
• Tanks: 6
• Aircraft: 1
• Infantry: two companies

Our losses:

• T-40 tanks: 4
• Killed: 32
• Wounded: 56
• Missing: 11"

Next in series: Battle at Semenovka

New Polling Scheme

It has been brought to my attention that the Blogspot blogging widget is awful. I already had a problem with it eating up votes, but it turns out that it reassigns them, too. As such, I put a little effort into it, and the polls will now be done through Google Forms. The functionality should remain largely unchanged, and you get to see all sorts of cool graphs (well, one cool graph).

If you have already voted in this week's poll, my apologies, as the responses were not carried over. Please vote again here.

Infantry vs Tanks

It's hard enough to be in a tank while fighting another tank, but what if you don't have a tank at all? When you're infantry, you might be unlucky enough to run into enemy tanks without as much as a 45 mm AT gun behind you. You have your rifle, some grenades, maybe an AT rifle squad somewhere nearby. Maybe a heavy machine gun crew. How well is all of that going to work against a tank? Let's find out.

CAMD RF 38-13355-806

First is a "heavy tank". I have no idea what it is, aside from that it's German. Here are the results with a 14.5 mm AT rifle:

• Lower front plate (45 mm at 10 degrees): does not penetrate
• Turret rear (28-30 mm at 10 degrees): penetrates at 200 meters, 100 meters at a 30 degree angle
• Turret platform side (28-30 mm): penetrates at over 300 meters, 100 meters at a 30 degree angle
• Lower hull side (28-30 mm): penetrates at over 400 meters, 100 meters at a 30 degree angle

Medium tank:

• Upper front plate (45 mm at 10 degrees): does not penetrate
• Lower front plate (45 mm at 12 degrees): does not penetrate
• Turret rear (34 mm at 8 degrees): penetrates at 100 meters, does not penetrate at a 30 degree angle
• Turret platform side (29 mm): penetrates at over 400 meters, 100 meters at a 30 degree angle
• Lower hull side (27 mm): penetrates at over 400 meters, 200 meters at a 30 degree angle

Light tank:

• Upper front plate (25 mm at 12 degrees): penetrates at 300 meters, 100 meters at a 30 degree angle
• Lower front plate (40 mm at 10 degrees): does not penetrate
• Turret (15 mm at 8 degrees): penetrates at over 500 meters at any angle
• Side (15 mm): penetrates at over 500 meters at any angle

Additionally, the light tank can be penetrated by the Mosin 91/30 rifle with the BS-40 bullet in the turret and side at 150 meters. 

That's it for this document. Let's fish out that 1942 report (CAMD RF 38-11355-832) that we all know and love, and see what it has to say.

The DShK heavy 12.7 mm machine gun (B-32 bullet), makes 4 dents 13 mm deep and 4 holes in the 15 mm rear armour of the Pz38(t). At 150 meters, all 4 hits are penetrations. At 200 meters, aiming at the side (15 mm at 70 degrees), there are 4 penetrations, and 9 13 mm dents. Closing in to 150 meters and firing at the side again leads to 7 penetrations and 2 14 mm dents. Conclusion: "The maximum distance for reliable penetration of the 15 mm side and rear armour is 150 meters."

The same machine gun is pitted against the PzIV. At 100 and 50 meters, it can only make 15-18 mm dents in the turret side. However, at 100 meters, it can penetrate the 20 mm side armour just fine. Aiming at the rear of the turret, it penetrates ones, and makes 4 18 mm dents. Aiming at the rear produces penetrations at 100 meters, but only 17-18 mm dents at 150 meters. Conclusion: "The turret cannot be penetrated by the 12.7 mm B-32 bullet. The side and rear can be penetrated at 100 meters."

CAMD RF 38-11355-778, a report by NII-48 on the quality of German armour, also has results of shooting at German tanks with various types of armament. The part that interests us for this article is the one where they use the DK 12.7 mm bullet. The penetration tests were performed at 700 meters and 50 meters.

• 10 mm of armour can be penetrated at up to 40 degrees from 700 meters, and up to 60 degrees from 50 meters.
• 15 mm of armour can be penetrated at up to 20 degrees from 700 meters, and up to 35 degrees from 50 meters.
• 20 mm of armour can be penetrated at up to 15 degrees from 50 meters.
• 15+15 mm armour plates can be penetrated at up to 5 degrees from 50 meters, but solid 30 mm armour plates cannot be penetrated at that distance at all.

The same bullet is tested against the PzII.

• The 15 mm armour on the sides can be penetrated from:
• 810 meters at 90 degrees
• 620 meters at 80 degrees
• 300 meters at 70 degrees
• not at all from 60 degrees
• The 15 mm of turret armour sloped at 15 degrees can be penetrated from:
• 440 meters at 90 degrees
• 360 meters at 80 degrees
• 50 meters at 70 degrees
• not at all from 60 degrees
• The 15 mm of rear turret armour sloped at 20 degrees can be penetrated from:
• 300 meters at 90 degrees
• 220 meters at 80 degrees
• not at all from 70 degrees

This report also pits the Pz38(t) against the 14.5 mm AT rifle. It can damage it at the following ranges and angles:

• Front: none
• Side: 
• 50 meters: possible to penetrate at 40-140 degrees, likely to penetrate at 47-133 degrees.
• 150 meters: possible to penetrate at 45-135 degrees, likely to penetrate at 50-130 degrees.

Ok, so these rifles and machine guns can take out 20-30 mm of armour no problem. But what about when you're faced with a Tiger? Then, you need to use explosives! CAMD RF 38-11377-12 has us covered.

First is the KB-30 Directed Impact Hand Anti-Tank Grenade. This mouthful weighs 1.1 kilograms. The grenades were thrown from behind a T-34 tank at a Tiger from 15 meters. Here are the results:

"Target: side. Angle: 50 degrees. Effect: 87 mm deep dent, 30 mm in diameter. Bump with crack on the inside.

Target: side. Angle: 90 degrees. Effect: breach 25 mm in diameter. On the inside, a fragment 100 mm in diameter and 12 mm thick was knocked out.

Target: side. Angle: 40 degrees. Effect: 85 mm deep dent, 35 mm in diameter. No damage on the inside.

Target: side. Angle: 40 degrees. Effect: breach 20 mm in diameter. On the inside, a 65-90 mm fragment was knocked out, following an existing crack. 

Target: turret. Angle: 25 degrees. Effect: 65 mm deep dent, 40 mm in diameter."

Conclusion: "The grenade can penetrate 65-85 mm of the tank's armour." Obviously, as with any armour piercing device, the closer the grenade hits to 90 degrees, the better. 

The next device is an anti-track TMD-B mine. The mine weighs 5 kg. The effect is as expected: "The T-VI hull was towed by a KV-1 tank. When the right track hit the mine, the mine detonated. As a result, the track was torn and the right drive wheel pins were damaged. A hole 600 mm deep and 1000 mm in diameter formed underneath."

The next weapon is a bit unconventional, a jumping mine, developed by factory #627. "Type: rifle grenade with a directed charge. The mine was placed close to the hull and detonated. As a result, the 28 mm thick bottom of the hull was penetrated. The breach was irregularly shaped, with torn edges, 27 mm by 35 mm. The jumping mine produced by factory #627 penetrates the bottom of the T-VI hull."

A number of AT rifles were tried, mostly ineffective, except the 43P Blum AT rifle. Firing a 14.5 mm bullet at 1500 m/s, it got some pretty impressive results. At 100 meters it penetrates the lower side hull of the Tiger at every attempt. When shooting at the thicker upper side hull, it penetrated once, and made 3 dents, 43-50 mm. 

Results of shooting the side of the Tiger with various AT rifles. The penetration from the 14.5 mm Blum bullet is #13. 

100 mm gun vs Tiger II

I've gone through nearly all of the guns that fired at the Tiger II in the CAMD RF 38-11377-129 report, so here's one of the remaining ones: the BS-3 gun, equivalent to the D-10, mounted in a SU-100 tank destroyer. At this point, there isn't much commentary I can make. We have already seen how poorly the fragile armour of the Tiger II performs. The BS-3 has no difficulty with it.

"Shot #12. Target: upper front plate. Distance: 500 meters.

Penetration. The shell hit the connection between the upper front plate and the lower front plate. Breach diameter: 150 by 230 mm entrance, 130 by 150 mm exit. On the opposite side, a piece of armour 260 by 320 mm , 85 mm thick, broke off.

Photo #18a, showing the damage done by shot #12.

Shot #13. Target: upper front plate. Distance: 1500 meters. Propellant: reduced. 

Dent, 165 by 200 mm, 80 mm deep. On the other side, an armour fragment 340 by 290 mm, 40 mm thick, broke off. A crack running all the way through the armour, 340 mm long, formed.

Shot # 14. Target: upper front plate. Distance: 700 meters. Propellant: reduced.

The shell hit a weakened portion of the armour. Penetration. Breach diameter: 165 by 210 mm entrance, 80 by 65 mm exit. A fragment 350 by 400 mm broke off the other side.

Shot #15. Target: upper front plate. Distance: 500 meters.

Dent, 170 mm by 240 mm, 80 mm deep. On the other side of the armour, a fragment 220 mm by 240 mm by 20 mm broke off. Cracks through the armour plate, 300 mm, 260 mm, and 170 mm long formed.

Shot # 16. Target: lower front plate. Distance: 1000 meters. Propellant: reduced.

Dent, 110 by 330 mm, 45 mm deep. On the other side, a 15 mm bump with a crack. Two cracks formed, 250 mm and 130 mm. The cracks are 12 mm wide.

Shot #17. Unsatisfactory. Ricochet from the ground.

Shot #18. Target: lower front plate. Distance: 300 meters.

Penetration. Shell hit the connection between the upper front plate and lower front plate. Penetration, 130 mm by 160 mm.

Shot #19: Unsatisfactory. The shell passed through the breach made by shot #18.

Shot #20. Target: lower front plate. Distance: 100 meters.

A piece 1000-1300 mm long fell off the lower front plate."

Photo # 24. Damage caused by shot # 20.

The damage is as we have seen previously. Even at ranges where the BS-3 cannot penetrate, spalling does the job. After a few shots at the LFP, it fell off entirely. At least, this time, no welding seams failed!

Soviet Tractor Tanks

Armoured tractors have frequently shown up in the 20th century, both as improvised fighting vehicles built by militias or resistance movements, and as organized attempts at creating a cheap and dirty armoured vehicle for a real army. This article covers armoured tractors built in the Soviet Union as more or less organized production efforts.

Masttyazhart AA Daimler

In 1925, as a part of the Mechanization and Tractorization of the Army program, Masttyazhart (Heavy Artillery Workshops) installed a 76.2 mm Model 1915 AA gun on a Daimler tractor (the model was not specified). The gun could rotate 360 degrees, had an elevation of up to 75 degrees, and depression of 0 degrees. The tractor towed a cart with 192 rounds of ammunition and a crew of six. It could only fire while stationary, with spades deployed. The vehicle was not mass produced.

D-10

Image from Solyankin et al, "Soviet Light Tanks 1920-1941", Zeughaus, 2007

This tractor-tank was developed in 1930 in Moscow. It was based on the Kommunar 9GU tractor, with 6-16 mm of armour, 4 machine guns, and one 76.2 mm model 1927 regimental gun facing backwards. The tractor could achieve 9 kph with a 75 hp engine. It was designed as a support tank, with one variant (D-14) capable of carrying infantry in it. The off-road capability was good, but reliability, crew ergonomics, and vision for the driver were deemed unsatisfactory. It is interesting to note the presence of a commander's cupola, giving the commander excellent 360 degree view range. The tank was not mass produced. 

D-11

Image from Solyankin et al, "Soviet Light Tanks 1920-1941", Zeughaus, 2007

The D-11 was a similar project to the D-10, but based on the Caterpillar-80. It had the same armament, but a weaker 60 hp engine, and a smaller fuel tank. It was not mass produced for the same reason as the D-10. The failures of the D-10 and D-11 projects made the Red Army seriously reconsider the viability of future tractor-tank projects.

SU-2 and SU-5

Image from Solyankin et al, "Soviet Self Propelled Guns 1923-1941", Zeughaus, 2008

The SU-2 self propelled gun was developed in 1931, at the Bolshevik factory. A 76.2 mm model 1902 divisional gun was mounted on a Kommunar 9GU tractor, behind an armoured shield. The gun could rotate 360 degrees. The tractor chassis had to be reinforced, and the driver's seat removed, in order to fit this modification. Armour thickness of the hull was 10 mm. The 75 hp engine accelerated the vehicle up to 12 kph. One of these vehicles was built. The vehicle had a crew of five.

In 1932, another, project at the Bolshevik factory put a 76.2 mm model 1915 AA gun on the same tractor. To compensate for the extra weight, the vehicle had no armour, and had four spades deployed when firing. One of these vehicles was built and passed trials, but the project was not continued due to the insufficient capacity of the Kommunar chassis to support 76.2 mm guns. This vehicle was designated SU-5, not to be confused with the SU-5 light triplex on the T-26 chassis.

NI-1

Early NI tank. Due to the highly improvised nature of manufacturing, two NI tanks can look vastly different.

NI, or Na Ispug (For Fear) was an improvised armoured vehicle, produced in Odessa. A STZ-5 tractor was equipped 10-20 mm of armour, or even mild steel with wooden boards, which would protect it from bullets. Armament varied based on what was available. NI tanks went into battle with 37 mm or 45 mm guns, 1-2 DT machine guns, sometimes only with a pipe to simulate a cannon. Some sources say that a 76.2 mm model 1938 mountain gun was used. The idea of the tank was not to combat other tanks, but to combat infantry, unprepared for the arrival of tanks, and lacking anti-tank weapons. The loud noise produced by this contraption contributed to the psychological impact of the tank. 55 of these tanks were built. The name NI was given to the after the war. During the war, they are designated as "tractor-tank". Three NI tanks exist to this day, at least one a reproduction for movies.

HTZ-16

Reproduction of a HTZ-16 tank in Kiev

Kharkov's approach to an armoured tractor was similar, but more uniform. A STZ-3 tractor was chosen for the job. It was equipped with 10-25 mm of armour, a 45 mm gun for enemy tanks, and a DP machine gun for enemy infantry. The turret of the tank did not rotate. Unlike with the NI, the HTZ-16 was set to be mass-produced, but problems with supplies limited the total production run to 60 at Kharkov and 30 at Stalingrad. At least one tank made it through the war and returned to its life as a tractor.

SU-2-2

CAMD RF 38-11355-190, a record of a meeting on turning obsolete tanks into tank destroyers, proposes installing the 57 mm ZiS-4 tank gun and, 37 mm and 25 mm automatic AA guns in the STZ-5 tractor "with extended hull and ZiS-16 engine". Meeting notes from Factory #92 list "SU-2-2, 57 mm tank gun on the fast artillery tractor STZ-5" as a potential option for production. However, this option was not chosen.

Voroshilovets 105-K

The same document proposes installing an 85 mm AA gun on a Voroshilovets tractor. The project was deemed unlikely, but launched at Factory #8 under the index 105-K anyway. A prototype was built, but not mass produced, due to the army's lack of heavy tractors.

ZiS-30

The ZiS-30 project was created by mounting a ZiS-2 57 mm anti-tank gun on a T-20 Komsomolets artillery tractor. This vehicle had 10 mm of armour in the front, and 7 mm on the sides and rear. It could reach a speed of 40 kph. The center of gravity was very high, leading to a chance of flipping the tank if the gun was fired without spades deployed. 101 of these vehicles were assembled over the course of about a month, and one with a 45 mm gun. The ZiS-30 performed well in combat, due to its powerful gun. However, the T-20 tractor was no longer produced in 1941. There were no spare parts for vehicles that managed to survive combat. Today, no ZiS-30s remain.

SU-2S

CAMD RF 38-11355-238

Despite a similar name, this project has nothing to do with the SU-2. It was developed in the fall of 1941, ten years later, at the Chelyabinsk Tractor Factory. A Stalinets-2 tractor, with a torsion bar suspension, had a 122 mm M-30 howitzer installed, and was armoured with anti-bullet armour (the Soviet "anti-bullet" category encompassed 4-20 mm of highly hardened steel). However, ChTZ became the new home of the Kirov factory, and started producing KV tanks, which were more important than this improvised solution. The M-30 howitzer found its way to an armoured hull in a few months, but one from a real tank.

Stalinets Tank Destroyer

CAMD RF 38-11355-639, fragment

In 1942, two engineers from the Ural Heavy Machinery Factory proposed a tank destroyer project. They intended to arm a Stalinets-2 tractor with a ZiS-5 gun, in a fully enclosed armoured hull. The resulting vehicle would have a crew of 3 and a height of only 1.8 meters. With only 25-32 mm of armour, and a reduced mass of 6-7 tons, the tank could theoretically reach a speed of 40 kph. The project was technically sound, but Stalinets-2 tractors were not built since 1941, and no compatible chassis was currently produced for this vehicle to ever be built.

T-150 Revival

I have written before about the Object 150, but its final fate was somewhat vague. Here is a document on that records it in more concrete terms.

CAMD RF 3722-95355-1

"KV tanks ## ... T-150 ... and T-28 tanks ## ... should be removed from the inventory of the regiment as non-recoverable losses." This is dated May 4th, 1943. The regiment in question is the 31st Independent Guards Tank Breakthrough Regiment.

However, the loss wasn't as non-recoverable as you might expect.

CAMD RF 3722-95355-1

This is an order of rewarding several drivers with the title of Mechanic-Driver First Class and assigning them to vehicles. All the way on the second page we see our old friend "KV" #T-150, assigned to the same 31st. This document is dated November 18th, 1943. Looks like 6 months is long enough to do the impossible!

45 mm APCR

By 1942, the penetrative power of the Soviet 45 mm anti-tank gun model 1932/37 has ceased to be very impressive. After studying captured German 37 mm PzGr 40 shells, and French 47 mm Komissan shells, NII-24 developed two types of APCR shells for it: one with a 20 mm tungsten carbide core, and one with a 28 mm tungsten carbide core. The shells were also manufactured with highly hardened steel cores. The requirements for the project were "penetration of a 60 mm armoured plate angled at 30 degrees, at a distance of 300-500 meters". Let's see how well they managed.

45 mm APCR type 1 (28 mm core, left) and type 2 (20 mm core, right). CAMD RF 81-12042-69

I will skip the metallurgical data, and get straight to the good stuff: penetration and accuracy.

The theoretical penetration calculations, against armour at 30 degrees, were as follows:

• 0 meters: 80 mm
• 100 meters: 74 mm
• 200 meters: 69 mm
• 300 meters: 65 mm
• 400 meters: 60 mm
• 500 meters: 56 mm
• 600 meters: 52 mm
• 700 meters: 48 mm
• 800 meters: 44 mm
• 900 meters: 40 mm
• 1000 meters: 37 mm

In theory, the engineers met the requirement. At 400 meters, the shell penetrated 60 mm of armour. Let's see how that translates into practical penetrations.

"Armour plate: 50 mm, cemented. Shell type: 1. Core type: steel. Distance: 120 meters.

Result #1: dent. On the rear side, spalling 5-6 mm deep. The core is stuck in the armour plate.

Result #2: penetration. Diameter 60-80 mm entrance, 30-45 mm exit. Core is destroyed. The plywood behind the target has a breach 150 by 100 mm. 

Distance: 100 meters.

Result #1: Armour is not destroyed. A dent is formed on impact. The core is destroyed.

Result #2: Penetration. Entrance diameter 90-70, exit diameter 40-35 mm."

Well, the steel core APCR is inconsistent, to say the least. Let's see what tungsten can do.

"Armour plate: 50 mm, cemented. Shell type: 1. Core type: tungsten carbide. Distance: 700 meters. Result #1: penetration. Diameter of breach: 75-40 mm entrance, 35-45 mm exit. The plywood behind the target has a breach 160 mm by 110 mm. Similar results are achieved by shot #2.

Shell type: 2. Core type: tungsten carbide. Distance: 450 meters. Result #1: penetration. Diameter of breach 25-40 mm entrance, 20-35 exit. Plywood behind the target has a breach 80 by 100 mm. Similar results are achieved by shot #2."

Much better! Let's see how steel does against a thicker target.

"Armour: 60 mm, non cemented. Shell type: 1. Core type: steel. Distance: 100 meters.

Result #1: No penetration. A dent 40 mm deep is formed. The core shattered.

Result #2: No penetration. A dent 35 mm deep is formed. The core shattered."

And back to tungsten, with the same armour plate:

"Shell type: 1. Core type: tungsten carbide. Distance: 400 meters. Results #1 and #2: penetration. Breach size 40-75 mm entrance, [missing] exit. Plywood behind the target has a breach 400 mm by 150 mm. 

Shell type: 2. Core type: tungsten carbide. Distance  380 meters. Results #1 and #2: penetration. Breach size 25-35 mm entrance, 20-25 mm exit. The core shattered. First shot makes a breach in the plywood behind the target 50 by 80 mm, the second 80 by 80 mm."

At this point, the testers ditch steel, and only test tungsten for larger thicknesses.

"Armour: 80 mm, non cemented. Shell type: 1. Core type: tungsten carbide. Distance: 300 meters. Results #1 and #2: penetration. Breach size 50-90 mm entrance, 30-45 mm exit. The core shattered. 

Shell type: 2. Core type: tungsten carbide. Distance: 250 meters. Results #1 and #2: penetration. Breach size: 20-50 mm entrance, 20-18 mm exit. The core shattered."

These results are very promising, much better than the calculations. Let's see what happens against thicker armour.

"Armour: 100 mm, non cemented, at 0 degrees. Shell type: 1. Core type: tungsten carbide. Distance: 65 meters. Result: penetration. Breach diameter 65 mm entrance, 30-20 mm exit. The breach has fragments of the core stuck in it. The plywood behind the target is also penetrated.

Shell type: 2. Core type: tungsten carbide. Result: penetration. Breach diameter is a caliber."

This is very promising! Note the impressive thickness of the armour. The calculations have been very pessimistic, as the shell can penetrate 25% more armour than predicted. Such a shell can defeat a Tiger, provided the gun is close enough. 

Accuracy figures are also provided in the report. At 500 meters, the maximum deviation of type 2 shells is only 20 cm in either direction. Type 1 shells have poorer accuracy, with deviation of 42 cm vertically and 33 cm horizontally. The inaccuracy of type 1 shells is explained by their inconsistent mass. 

Something interesting to compare: along with captured German 37 mm shells, a document was captured describing them as only useful up to 300 meters. The realistic range for these 45 mm APCR shells is listed as 500 meters. Comparing penetration, the 37 mm PzGr 40 shells only penetrate a 30 mm armour plate at 30 degrees at 300 meters, and cannot penetrate a 40 mm plate. The 45 mm APCR shells could penetrate an 80 mm plate at 30 degrees at this distance. 

However, you may still be reeling from the suggestion that a 45 mm tank gun can take out a Tiger. A small caliber gun, on T-70 or even T-26 light tanks! Preposterous! Or is it?

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"As a result of shooting the Tiger with a 45 mm tank gun, it is determined that:

• a subcaliber shell penetrates the lower side hull, 62 mm thick, at 350 meters.
• a subcaliber shell penetrates the upper side hull, 82 mm thick, at 200 meters."

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"Photo #7. Penetrations from a 45 mm AT gun.
XX: penetration 20 mm in diameter, crack along welding seam 200 mm in length. Distance: 200 meters.
XXI: penetration 20 mm in diameter. Distance: 350 meters.

Photo #8. Penetrations from a 45 mm AT gun.
1: penetration, 30 mm in diameter. A crack formed from 50 mm from the breach to the edge of the armour plate.
5: penetration, 20 mm in diameter. Distance: 350 meters.

As a result of shooting at a Tiger with a 45 mm AT gun, it is determined that: 

• a subcaliber shell penetrates the lower side hull, 62 mm thick, from 500 meters.
• a subcaliber shell penetrates the upper side hull and turret side, 82 mm thick, from 350 meters."

Pretty impressive for such a small caliber!

Artillery T-34 and KV

I talked about mortars on a T-34 before, but this is an even more ambitious project. A 400 mm mortar was to be installed on a T-34.

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The mortar would be transported facing forwards, but could only fire facing to the side, with spades deployed. Otherwise, the massive recoil would destroy the T-34 chassis.

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The T-34 plan was, technically, just a backup. The main bearer of the 400 mm mortar was to be the KV-1S. The chassis weighed 37 tons. The mortar would weigh 50 tons. Just as with the T-34, the spades are present, since even the more robust KV chassis could not take that kind of recoil.

Neither project progressed past the blueprint stage.

There was another failed plan to make a KV-1 into an artillery platform, this one using Katyusha rockets. 

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While the rockets were traditionally used for indirect fire, there were several situations where the rockets had to be aimed directly at enemy tanks, with great effect. This project was also never built.