Consider the Japanese problem first. During the battle in the Yellow Sea, the Japanese suffered heavy artillery losses from their own shells. One 12 "gun on the Mikasa, two 12" guns on the Asahi, and one 12 "gun on the Sikishima tore apart. At the same time, the entire tower on the flagship Mikasa was destroyed, heavy losses (according to various sources, 21 or 22 people) were carried by the gunners.
Bursting of the trunk of the Mikasa stern tower in the Yellow Sea:
There are several versions explaining the reasons for barrel bursts. One of them is known from an English observer's report in Japanese navy W.C. Packingham:
Arsenal workers attribute this damage not to shell defects, but to the fact that the charges were placed in a gun that was highly overheated by continuous firing, and they recommend that after about 20 shots fired at a fast pace, the guns are cooled with water from a hose starting from the inside. These workers say that heating the gun accelerated the combustion of the charge, thereby significantly increasing the pressure, and that the pressure exceeded the permissible parameters that the shells of the shells could withstand, and their bottoms were pushed inward, and the explosives inside the shell ignited from temperature and pressure at the rate of combustion almost corresponding to the detonation effect.
But this version is rather doubtful due to the fact that the gunpowder was in the gun for a rather short time and could not heat up significantly. In addition, no one else encountered similar problems, although the same cordite was massively used by other countries and not only in the navy.
The second version is that the detonation of the projectiles was caused by gas breakthroughs through leaks in the fuse thread. This version is voiced in the article by Koike Shigeki and is indirectly confirmed by the work carried out by Japanese specialists to replace the shells and refine the fuse bodies. According to the documents of the Kure arsenal, the most important requirement in these works was the preservation of the high sensitivity of the fuses. Thus, the assumption of W.K.Packinham that the sensitivity of the fuses to Tsushima was reduced is refuted.
The third version explains the breaks by the fact that a very sensitive fuse was triggered due to the slowing down of the projectiles caused by copper plating of the barrel bore (copper from the leading belts of the projectiles settled on the inner surface).
In addition, it was noticed that mainly armor-piercing shells exploded in the barrels, and even a temporary ban was introduced on their use. In December 1904, the British observer in the Japanese fleet, T. Jackson, reported that Japanese officers were unanimously repeating about the unsuitability of the existing armor-piercing shells and wanted to get "normal" shells in their cellars, i.e. equipped with black powder. In April 1905, the Japanese fleet even began to receive new armor-piercing shells with black powder, and even on May 4, 1905, the Sikishima fired such shells experimentally, but the accuracy was found to be unsatisfactory. The use in Tsushima of shells other than those with an ijuin and shimozu fuse has not been documented. The only case of the use of "old" shells in the entire Russo-Japanese War was recorded on August 1, 1904 in the Korean Strait, where Izumo fired 20 8 "shells equipped with black powder.
In order to avoid overheating the barrels, the Japanese in Tsushima slowed down the rate of fire of their main battery guns compared to the battle in the Yellow Sea, used a special water cooling system for the barrels, and minimized the use of armor-piercing 12 "shells. But that did not help either! gun on "Mikasa" (and there were two explosions, the first happened shortly after the projectile was fired from the barrel and did not cause harm), one 12 "gun on" Sikishima "and three 12" guns on "Nissin" (the Japanese themselves write that on " Nissine ”the barrels were torn off by Russian shells, but the photographs and the testimony of British observers do not confirm the official version). In addition, self-destruction of several smaller-caliber guns were recorded. One 8 ”tore apart into Izumi, Chin-Yen and Azuma. Moreover, on the Azuma, the Japanese did not recognize self-rupture, and the separation of the tip of the barrel was attributed to a fragment of a Russian 6 ”projectile that exploded overboard. One 12-mm gun exploded into Mikasa, Chitose and Tokiwa.
"Nissin". Bursting of the trunk of the stern tower in Tsushima:
"Shikishima". The barrel torn apart in Tsushima:
In general, speaking about the problem of explosions, one should assess it as very serious, since the fire potential of the fleet suffered greatly from its own shells. For example, during the battle in the "Yellow Sea" more than 30% of the 12 ”barrels were out of order. And in Tsushima, it was necessary to reduce the rate of fire with large caliber, and, consequently, the fire effect on the enemy.
Comparison of the consumption of shells of the main caliber:
In this regard, it should be recognized that the imperfection of the shells seriously affected the efficiency of the Japanese fleet.
Now we will deal with the "Russian" problem and for this we will study the device of a two-capsular bottom shock tube of the delayed action of AF Brink's design, which is used on our "pyroxylin" shells.
When fired, the extensor (5) by inertia moves back and unbends the safety catch (4). When hitting the target, the tuba firing pin (6) hits the rifle capsule (9), which ignites the powder firecracker (11). Under the action of propellant gases, the aluminum firing pin (10) opens the safety sleeve (12) and, with a shock, ignites the detonator cap with explosive mercury (14). It ignites two sticks of dry pyroxylin (15 and 16) and then detonates wet pyroxylin, which is stuffed with the projectile.
At the end of Tsushima, the Brink pipe, which had a lot of complaints, was studied very closely (including tests) and the following weak points were found in it:
1. If a projectile (especially a large one) was not decelerated sharply, for example, when it struck thin unarmored parts of a ship or water, the inertial force of the striker might not be enough to ignite the rifle capsule (design pressure not less than 13 kg / cm2) But this is a feature of the fuse for an armor-piercing projectile, because it should not be initiated by hitting a thin metal.
2. Defect of the aluminum striker, when due to low hardness it could not ignite the detonator cap. Initially, the sufficient hardness of the striker was ensured by the presence of impurities in aluminum, but the shells of the 2nd Pacific Squadron were hit by a striker made of cleaner and, accordingly, softer aluminum. After the war, this firing pin was made of steel.
3. The problem of breaking the brass body when hit too hard.
4. The problem of incomplete detonation of the explosive in the projectile due to the too small volume of dry pyroxylin in the fuse.
The list of disadvantages is impressive! And it seems that there is every reason to call the "damned" pipe the main culprit of Tsushima, but ... we have the opportunity to evaluate its real work according to Japanese sources. With the only limitation: due to the lack of data on 6 "and smaller shells, we will not consider them. Moreover, according to claim 1., the defect is most pronounced precisely on large shells, which means that this should not greatly distort the real picture.
To analyze the hits on Japanese ships, I used the damage schemes from Top Secret stories», Analytical materials by Arseny Danilov (https://naval-manual.livejournal.com), monograph by V.Ya. Krestyaninov's "Battle of Tsushima" and an article by N.J.M. Campbell "The battle of Tsu-Shima" ("The Battle of Tsushima"), translated by V. Feinberg.
I will give the statistics of hits of large shells (8 ... 12 ") on Japanese ships in Tsushima according to the data of Arseny Danilov (they are more elaborate and accurate than the data of Campbell or Krestyaninov). The numerator indicates the number of hits, in the denominator - continuity:
Mikasa 6 ... 9/0
Fuji 2 ... 3/2
"Asahi" 0 ... 1/0
"Asama" 4 ... 5/1
"Iwate" 3 ... 4/1
In total, from 27 to 34 hits with shells of 8 ... 12 "caliber, of which 6 are non-breaks (18-22%), and it seems that this is a lot! But we will go further and consider each case separately to find out the circumstances of the hits and their possible effect ...
1. "Shikishima", time is not specified. A projectile with a caliber of about 10 "pierced the cargo boom of the mainmast without explosion or loss. The reason for the non-rupture is most likely the weak force of the impact on the obstacle. This hit could not cause serious damage due to the high height above the deck.
2. "Fuji", 15:27 (15:09). Hereinafter, first Japanese time, and in brackets - Russian according to Krestyaninov. A shell, presumably 10 ... 12 ”, pierced through the base of the bow tube and the right fan of the bow boiler room, without an explosion. 2 people were injured. The reason for the failure is still the same. The explosion of the projectile could theoretically cause noticeable damage on the deck, the bridge and, with very great luck, in the boiler room.
3. "Fuji", 18:10 (17:52). The projectile, presumably 6 ... 12 ”, overcame the bridge fence, ricocheted against the roof of the forward conning tower and flew overboard. The roof of the conning tower was damaged, 4 people were injured, including the senior mine officer was seriously wounded in the conning tower, the senior navigator was slightly injured. The reason for the non-rupture is probably in the very large angle of encounter with the obstacle. The explosion, even if it had happened, would not have caused serious damage after the ricochet.
4. Izumo, 19:10 (18: 52-19: 00). The 12 ”shell pierced the port side, several bulkheads, the upper deck, the middle deck, slid along the armored deck and stopped in coal pit # 5 on the starboard side without exploding. This hit killed 1 and wounded 2 people in the boiler room. The reason for the non-rupture is difficult to attribute to the weak force of the blow, most likely there was some serious defect. If the shell exploded, it would not have inflicted critical damage not near the boiler room, but during the passage of the upper deck and critical damage; there could have been significant damage and more casualties.
5. Asama, 16:10 (15: 40-15: 42). The shell pierced through the base of the rear chimney, which led to a sharp drop in thrust in the boiler furnaces, and the speed of the cruiser dropped to 10 knots for a while, because of which it again lost its place in the ranks. According to V.Ya. Krestyaninov, this shell exploded, but the Japanese schemes suggest otherwise. In the documents, the caliber of the projectile is estimated at 6 ", but the size of the holes in the casing and pipe (from 38 to 51 cm) suggests that the pipe was pierced by a 12" projectile. The reason for the non-rupture is probably the weak impact force. The effect of the hit was maximum and without an explosion.
6. "Iwate", 14:23 (-). An 8 "(10" according to the Sasebo shipyard) projectile pierced the starboard side at the level of the lower deck at the base of the aft tower of the main battery, ricocheted off the bevel of the lower deck, broke through several bulkheads and stopped. There were no casualties, however, through this hole and the adjacent one (a 152-mm shell exploded a little closer to the stern), water entered the ship, filling two compartments on the lower deck by 60 centimeters. The reason for the non-rupture is a clear defect. In the event of a standard projectile firing, there might have been losses among personnel and flooding of adjacent compartments.
Now we can summarize. In no case of non-detonation was there a hit in the vertical armor. In three episodes, there were hits to pipes and masts with a clearly weak impact on an obstacle, which can be attributed to the "features" of armor-piercing fuses. In one - a very sharp angle of encounter, under this circumstance, even the shells of the next generations often did not explode. And only in two cases there are serious arguments to suspect fuse defects. And these two cases give only about 6% of non-breaks from the total number of hits with large shells, which almost fits into the "norm" voiced by V. I. Rdultovsky (5%).
Well, if we talk about the possible consequences, then in no case would the rupture (if it happened) would affect the course of the battle. Thus, it can be concluded that there was a problem in the Russian navy due to the equipping of high-explosive shells with "armor-piercing" shock tubes, but not because of the abnormally high proportion of defects in large-caliber shells. And in general, the problem of non-explosions of Russian shells should be considered much less acute than the problem of bursting of the barrels of Japanese guns from the detonation of shells during a shot.
In the next part, we will consider, systematize and compare the effect of Russian and Japanese shells on the armored parts of the ship.