Question about the B-25 G/H 75mm gun mount

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Jim D Burns
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Question about the B-25 G/H 75mm gun mount

Post by Jim D Burns »

I know the games code allows PT boats and barges to be strafed by aircraft machinegun mounts when they are set to 100 foot altitude, but I thought attacks on regular shipping set to 100 feet defaulted to the skip bombing code. I’ve never seen a bomber strafe anything that I can remember.

So my question is, will the 75mm gun mounted on the B-25 G/H airframes in CHS be used for anything or are they just there for historical esthetics. With a penetration rating of 80, they’re better than a DD 5 inch gun, so it would be nice to be able to see these used in action somehow.

Has anyone ever seen these planes use their big gun for anything? Perhaps shredding a sub on ASW? Do they ever strafe an airfield with them instead of dropping bombs?

Jim
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Feinder
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RE: Question about the B-25 G/H 75mm gun mount

Post by Feinder »

I do believe I've seen my level bombers using guns (strafing) if set to 100' (altho I haven't played CHS far enough to the B-25G/H yet).

The real problem you're going to have is that the 75mm boomer has an accuracy of "2".  Good luck actually hitting anything with it. I -also- believe that aircraft strafing ships actually only make one pass on a target.

Also cosider what your one rare hit is going to actually do. Most DDs and transports will soak up 8 - 10x 5" shells before sinking, so that rare hit (on one pass!) will make a nice boom if you actually manage to hit; but you'll likely be disappointed with the actual damage (it's not like the ship is going to go down over one hit anyway).

-F-
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John Lansford
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RE: Question about the B-25 G/H 75mm gun mount

Post by John Lansford »

IIRC the 75mm in the B-25H had an autoloader for its limited supply of shells, so it should be somewhat more accurate than a "2".  I do recall reading of a B-25H pilot that shot down a Mavis with the thing, and hits on barges and small patrol boats were routine by experienced pilots as well.
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Feinder
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RE: Question about the B-25 G/H 75mm gun mount

Post by Feinder »

I would say the Catch-22 for the accuracy is that,
1.  Vs. ships you get one pass.
2.  Vs. aircraft, there are no ammo limits, and that cannon is listed as "aircraft cannon" so it -can- be use air-to-air as well.  Also the accuracy of a weapon is usually adjusted up, due to higher rate of fire (which is probably partly why 75mm accuracy is so low in CHS, low ROF). 
 
If you up the accuracy to say a 20 or so in order to hit ships on the one pass; that would certainly give better results.  But given that most aircraft guns have an accuracy of 25 - 35, if you put a 75mm cannon with an accuracy of 20, you basically create a 75mm auto-cannon vs. aircraft (boy would -that- be fun).
 
I dunno.  Maybe if you set the accuracy to 12 or so....?
 
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RE: Question about the B-25 G/H 75mm gun mount

Post by ChezDaJez »

ORIGINAL: Jim D Burns

I know the games code allows PT boats and barges to be strafed by aircraft machinegun mounts when they are set to 100 foot altitude, but I thought attacks on regular shipping set to 100 feet defaulted to the skip bombing code. I’ve never seen a bomber strafe anything that I can remember.

So my question is, will the 75mm gun mounted on the B-25 G/H airframes in CHS be used for anything or are they just there for historical esthetics. With a penetration rating of 80, they’re better than a DD 5 inch gun, so it would be nice to be able to see these used in action somehow.

Has anyone ever seen these planes use their big gun for anything? Perhaps shredding a sub on ASW? Do they ever strafe an airfield with them instead of dropping bombs?

Jim

Yes, they will. In my game with Bradfordkay. his B-25G/Hs strafed one of my bombardment groups that was retiring. He scored 28 hits with the 75mm and had several deck armor penetrations. Hard to say how much damage was incurred as Takao also ate a PT torp in the same turn but I will say that the sys damage far outweighed the flot damage. The strafing also took out a 5" mount and an AA mount.

Chez
Ret Navy AWCS (1972-1998)
VP-5, Jacksonville, Fl 1973-78
ASW Ops Center, Rota, Spain 1978-81
VP-40, Mt View, Ca 1981-87
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ChezDaJez
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RE: Question about the B-25 G/H 75mm gun mount

Post by ChezDaJez »

ORIGINAL: Feinder

I do believe I've seen my level bombers using guns (strafing) if set to 100' (altho I haven't played CHS far enough to the B-25G/H yet).

The real problem you're going to have is that the 75mm boomer has an accuracy of "2".  Good luck actually hitting anything with it. I -also- believe that aircraft strafing ships actually only make one pass on a target.

Also cosider what your one rare hit is going to actually do. Most DDs and transports will soak up 8 - 10x 5" shells before sinking, so that rare hit (on one pass!) will make a nice boom if you actually manage to hit; but you'll likely be disappointed with the actual damage (it's not like the ship is going to go down over one hit anyway).

-F-

Unfortunately, not quite the case...

Day Air attack on TF at 47,88

Allied aircraft
Kittyhawk III x 15
P-40N Warhawk x 20
B-25G/H Mitchell x 8

Allied aircraft losses
B-25G/H Mitchell: 5 damaged

Japanese Ships
CA Takao, Shell hits 20, on fire



...and in the same turn...


Day Air attack on TF at 47,88

Allied aircraft
Kittyhawk III x 13
P-40N Warhawk x 12
B-25G/H Mitchell x 12

Allied aircraft losses
B-25G/H Mitchell: 8 damaged

Japanese Ships
CA Takao, Shell hits 8, on fire


Remember though that this occurred after the PT torp hit.

Chez
Ret Navy AWCS (1972-1998)
VP-5, Jacksonville, Fl 1973-78
ASW Ops Center, Rota, Spain 1978-81
VP-40, Mt View, Ca 1981-87
Patrol Wing 10, Mt View, CA 1987-90
ASW Ops Center, Adak, Ak 1990-92
NRD Seattle 1992-96
VP-46, Whidbey Isl, Wa 1996-98
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John 3rd
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RE: Question about the B-25 G/H 75mm gun mount

Post by John 3rd »

The man I talked to a veteran with Barbie 3 (the Thread of pictures and video on a B-25J) said that most of the J model's cannon was HAND LOADED.  This came from an actual veteran of New Guinea who flew them...
 
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Feinder
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RE: Question about the B-25 G/H 75mm gun mount

Post by Feinder »

Well that's cool. I don't mind being corrected.

[:)]

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RE: Question about the B-25 G/H 75mm gun mount

Post by Jim D Burns »

ORIGINAL: John 3rd

The man I talked to a veteran with Barbie 3 (the Thread of pictures and video on a B-25J) said that most of the J model's cannon was HAND LOADED.  This came from an actual veteran of New Guinea who flew them...

I found this site with some good info on the B-25. The G and H models were the only ones with the 75, both configurations were hand loaded. The J model reverted back to the same nose as the C model, but with far more machine guns. Some had as many as fourteen M-2s (.50 cal) mounted firing forward from the nose.

Jim
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RE: Question about the B-25 G/H 75mm gun mount

Post by Jim D Burns »

ORIGINAL: ChezDaJez
Yes, they will. In my game with Bradfordkay. his B-25G/Hs strafed one of my bombardment groups that was retiring.

Hi Chez,

Thanks for the info, glad to know I can get them to use the mount. Could you ask your opponent if he had the bombers set for standard naval attack and they dropped down and strafed on their own, or if they were intentionally set to 100 feet?

Thanks,

Jim
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RE: Question about the B-25 G/H 75mm gun mount

Post by John 3rd »

If you check the pictures I posted, you will count 14 .50s on that B-25 plus the 75 and bombs.  That is some SERIOUS firepower!
 
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Dili
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RE: Question about the B-25 G/H 75mm gun mount

Post by Dili »

B-25G/H Mitchell x 8

Allied aircraft losses
B-25G/H Mitchell: 5 damaged

Japanese Ships
CA Takao, Shell hits 20, on fire

Those pilots and loaders are good if they made only one pass. 75mm's could get at most 3 hits by pass being 2 the usual. What's the experience?
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Feinder
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RE: Question about the B-25 G/H 75mm gun mount

Post by Feinder »

Well, you'd have to ask Chez or BK what's actually shown on the replay.  But those 20 hits aren't necessarily all 75mm hits.  Many could be (and probably are), 50-cal hits.
 
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RE: Question about the B-25 G/H 75mm gun mount

Post by castor troy »

ORIGINAL: Feinder

Well, you'd have to ask Chez or BK what's actually shown on the replay.  But those 20 hits aren't necessarily all 75mm hits.  Many could be (and probably are), 50-cal hits.

-F-


I´ve also thought about the cal .50
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RE: Question about the B-25 G/H 75mm gun mount

Post by HansBolter »

ORIGINAL: Jim D Burns
ORIGINAL: John 3rd

The man I talked to a veteran with Barbie 3 (the Thread of pictures and video on a B-25J) said that most of the J model's cannon was HAND LOADED.  This came from an actual veteran of New Guinea who flew them...

I found this site with some good info on the B-25. The G and H models were the only ones with the 75, both configurations were hand loaded. The J model reverted back to the same nose as the C model, but with far more machine guns. Some had as many as fourteen M-2s (.50 cal) mounted firing forward from the nose.

Jim

Are you sure that all 14 were mounted in the nose or was there a total of 14 throughout the aircraft including the nose mount? Having built an old model kit of the B-25 (don't remember the exact model) that had 4 in the nose with dual blister mounts on either side of the fuselage near the nose supplementing the additional mounts elswhere in the plane for a total of 12, I don't see how 14 could have ever possibly fit in the nose alone.
Hans

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RE: Question about the B-25 G/H 75mm gun mount

Post by John Lansford »

ISTR that the B-25H model I made had 4 0.50 caliber MG's in a row above the 75mm, four MG's in single sponsons along the fuselage firing forward (2 to a side), two in the upper turret, two in the tail, and two singles in the fuselage behind the wing, for a total of 14 machine guns.  If the 75mm was removed (again IIRC) they could put in 4 additional .50 caliber MG's in the nose.
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RE: Question about the B-25 G/H 75mm gun mount

Post by Doggie »

The 14 forward firing fifties include the dorsal turrent, which could be locked to face forward.
 
So that's between four and eight guns in the nose; four in blister packs on the side, and two in the top turrent, which would add up to a max of fourteen.
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RE: Question about the B-25 G/H 75mm gun mount

Post by Cap Mandrake »

Here is one with 8 fixed forward plus the 75.

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RE: Question about the B-25 G/H 75mm gun mount

Post by Jim D Burns »

ORIGINAL: HansBolter
Are you sure that all 14 were mounted in the nose or was there a total of 14 throughout the aircraft including the nose mount? Having built an old model kit of the B-25 (don't remember the exact model) that had 4 in the nose with dual blister mounts on either side of the fuselage near the nose supplementing the additional mounts elswhere in the plane for a total of 12, I don't see how 14 could have ever possibly fit in the nose alone.

I was basing it on this paragraph from the site I linked:
The B-25J reverted to the greenhouse bombardier nose of the "C" model, but with far more firepower. Some variants had as many as 14 forward firing M-2 machine guns in front and four more at various other stations in the craft. The 75mm cannon was removed and a bombardier was again added as the sixth crewman. B-25Js were by far the largest production run of the Mitchell bomber with more than 4,300 copies delivered before the war ended and production lines of the B-25 were shut down for good.

So I guess I was wrong in assuming all forward machineguns were nose mounted, but it definitely does not include the other 4 machineguns in the count. So 18 machineguns total, but only for *some* variants. What numbers were actually produced with this kind of firepower is anybody's guess.

Jim
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RE: Question about the B-25 G/H 75mm gun mount

Post by John 3rd »

This is the exact model of B-25 I saw Sat/Sun at the airport.
ORIGINAL: Cap Mandrake

Here is one with 8 fixed forward plus the 75.

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