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Early Aviation
Discuss World War I and the early years of aviation thru 1934.
1930s US machine guns?
Jessie_C
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British Columbia, Canada
Joined: September 03, 2009
KitMaker: 6,965 posts
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Posted: Friday, March 20, 2020 - 11:22 AM UTC
Hi all,

Here's a bit of an odd question. In P-12s and F4B-4s, one gun was often .30 Cal, and the other .50, but was there generally a set standard for which was which? (e.g. .30 on the left, .50 on the right?)
Or was it entirely up to the armourers and could be either way?
Kevlar06
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Washington, United States
Joined: March 15, 2009
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Posted: Friday, March 20, 2020 - 11:55 AM UTC
Jessie, that’s a good question. I was building an F4B a few years ago, and all the research on the ‘net indicated the gun positions were interchangeable. But, I’ve also seen info the .30 was on the left and the .50 on the right frequently. Since that time, I’ve acquired several books on P-12s and F4Bs, so I’ll do some checking in them for you. The .50 has an interchangeable feed from side to side, I’m not sure about the .30, but it may also have the ability to be interchangeable. Barrel jackets are of the “British” type with the rectangular cooling holes vs. the later round holes. They also had barrel extensions through the fuselage troughs.
VR, Russ
gastec
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Auckland, New Zealand
Joined: February 03, 2014
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Posted: Friday, March 20, 2020 - 03:11 PM UTC
Wikepedia has the .30 cal as feeding from the left side but later notes an M2 dual mount with opposings feeds. So that would surely indicate the gun could be fed either side?
Kevlar06
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Washington, United States
Joined: March 15, 2009
KitMaker: 3,670 posts
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Posted: Saturday, March 21, 2020 - 07:24 AM UTC
Jessie,
I stand corrected. When I got a chance this AM, I first checked my 1/32 F4B, and found I’d mounted my .50 on the left, the .30 on the right (just the opposite of what I said in the first post—I’m getting old). Asking myself if I screwed this up, I went to check my references (The American Fighter Plane, P12 in Profile, F4B in Profile, and Squadron’s P12/F4B in Action). In all the photos of the cockpit, of which there were several, they clearly show the .50 on the left, the .30 on the right (like I did in my F4B). The ejection chute of the .50 comes up the left side of the fuselage, while the .30 comes up the right. Ammo boxes are mounted closer to the centerline of the cockpit behind the instrument panel. These pubs also have photos of the clearly longer mounts for the .50 on the left, .30 on the right. One photo in the Squadron “in Action” book shows the clearly larger .50 mounted on the left. However, given the fact the aircraft could be mounted with either one of each gun, or two .30s, it would seem to me they could be alternately mounted on either side, BUT, and this is a really big question, the larger ejection chutes and ammo boxes for the .50 would need to be “re-located” and “re-handed”. None of my pubs had anything written about which gun would be mounted right or left, but all photo evidence indicates the .50 was likely on the left. Hope this information helps.
VR, Russ
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