Synchronised Aircraft guns

No, it’s just that these US documents always give the most favorable RoF for the guns.

The RoF of guns generally fluctuate depending on the projectile mass and the resulting recoil forces.

The different projectile mass of the MG 151 and 151/20 shells can be substantial.

So while the manual basically gives an average of 700 RPM, the RoF for heavier shells could easily reach 800 RPM.

The MG 151 was generally loaded with more 57g explosive rounds than the 72g AP-T and the MG 151/20 manual has a weight for 20mm Mineshells of merely 86g compared to the shells which were 115g at that time.

The RoF of the MG 151/20 probably slightly increased over time, as the Mineshells got heavier and the other shells slightly as well.

Same story with the Ho-5, which either fired super light 84.5g shells or 123g AP shells, even heavier than the MG 151/20 shells.

So the RoF could be as low as 700 RPM but as high as 950 when firing AP-T.

Of course they only loaded a single AP for every two or three other rounds, so the practical RoF was 800 RPM or lower.

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But you still took the middle average then?

Well, of course.

The RoF has to be one value and the average makes the most sense.

That makes so much sense.

The in-game Ho-5 is 950 rpm.
Ho-103 is at 900 rpm.
There is no synchronization delay in the game.
Anyone touched FMod to mod war thunder audio would know that.
The fire rate of all ww2 guns are constant regardless of the mounting method in this game. The feature is not implemented as of yet.
You can see the obvious difference.
If you are using one of the logitech mouse or a keyboard, you can bind the loop macro with the specific interval per shot.
Doing this in an onlune match might send too much user imput to the server and snail might detect it weird. So it’s better to stick in mission editor sessions.

I’m in-line with using 825RPM for Ho-5 as the practical middle point. Then reducing the fire rate depending on the mounting method but no propeller rpm involvement. Just to familiarize. But it could be better to take the propeller rpm into the account.
It’s definitely better than the current behavior of the guns.

The muzzle velocity must be from confusing 151/20 with 151/15.

Here is data from Japanese sources on the actual RoF of synchronized machine guns used on the A6M. Among these, the Type 3 MG was based on the Browning design and used the 13.2×99 mm Hotchkiss cartridge. Although it is often said that Browning-type guns suffer a significant reduction in RoF when synchronized with a propeller, this does not seem to have been the case with the Type 3 MG.

Gun RoF Synchronized
7.7 mm Type 97 MG 950 650-750
13.2 mm Type 3 MG 800 600-700

When fitted with synchronization gear, the rate of fire becomes 600–700 rounds per minute.
同調装置とするときは発射速度は600~700となる

Spoiler

Source: “零式艦上戦闘機 歴史群像 太平洋戦史シリーズ, Zero Fighter, Rekishi Gunzō: Pacific War History Series Vol. 12.” Published by Gakken, 1996, ISBN-13: 978-4056012620, p. 91.

The Type 3 MG was equipped with the Type 3 synchronization gear.
https://dl.ndl.go.jp/en/pid/4009539/1/14
DATA ON THE TYPE 3 SYNCHRONIZER & SYNCHRONIZER CONTROLLER, YOKOSUKA Naval Air Group, April 1944. Captured on SAIPAN.

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Similar what I got, using an general approach.

Maybe there still some hope.

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That report was prepared by me, but it is the Army’s Type 89, not the Navy’s Type 97. I would like to add this just to be sure.
https://community.gaijin.net/issues/p/warthunder/i/KZosxgmRAoN3

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Oh right. I was thinking about the Army Type 89 😵‍💫

In WT the Type 97 has 900 RPM as far as I remember 🤔

https://community.gaijin.net/issues/p/warthunder/i/jFGsb9oyS2LL

Well, there you have it.

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