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 Author  Topic: Stern 20 mm cartridge bag?
PeterTareBuilder

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of PeterTareBuilder  Posted on: Apr 20, 2011 - 7:31am
Hi guys.

Hoping to spark my interest and get building again I have a few questions for you about the stern mounted 20 mm gun on the PT-103 class of boats.

Was the cartridge bag used very often in actual combat?

When the gun was in operation did smoke come out of the ejection port as well as the muzzle?

What was the rate of fire? I know the capacity of the magazines but I need to rediscover the rate of fire.

I assume that the 20 mm gun was fired in bursts. Is that correct? If so about how many rounds were fired per burst?

Thanks again and cheers from Peter

"Give me a faster PT boat for I'd like to get out of harm's way!"

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Frank J Andruss Sr

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Frank J Andruss Sr   Send Email To Frank J Andruss Sr Posted on: Apr 20, 2011 - 9:13am
Pete

Many of the photos I have of diffferent PT BOATS had those cartridge bags removed. I think the two items removed from these weapons were the Cartridge Bag and the heavy twin shields. You already know that these guns mounted on the boats had 60 rounds in the drum. Rate of fire in the book called for 450 rounds per minute, but I suggest this may have been closer to 250 rounds per minute. I spoke with 2 gunners mates this afternoon, who made mention that they usually tracked a target, then hit the trigger, sending out at least 10-20 shells before laying off the trigger, then hitting it again. I would bet this changed if they were under attack by planes. You could send 9,000 rounds through a barrel before having to change it out. There was a muzzle flash from this weapon, but not sure about the breech. I would guess each gunner had his own way of firing the gun, but I never heard of any 20mm barrel getting anywhere near as hot as the twin .50's if depressing the triggers too long. I do not have a 20mm Manual, but I am sure someone on the board does.


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PeterTareBuilder

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of PeterTareBuilder  Posted on: Apr 20, 2011 - 12:23pm
Quote:

Pete

Many of the photos I have of diffferent PT BOATS had those cartridge bags removed. I think the two items removed from these weapons were the Cartridge Bag and the heavy twin shields. You already know that these guns mounted on the boats had 60 rounds in the drum. Rate of fire in the book called for 450 rounds per minute, but I suggest this may have been closer to 250 rounds per minute. I spoke with 2 gunners mates this afternoon, who made mention that they usually tracked a target, then hit the trigger, sending out at least 10-20 shells before laying off the trigger, then hitting it again. I would bet this changed if they were under attack by planes. You could send 9,000 rounds through a barrel before having to change it out. There was a muzzle flash from this weapon, but not sure about the breech. I would guess each gunner had his own way of firing the gun, but I never heard of any 20mm barrel getting anywhere near as hot as the twin .50's if depressing the triggers too long. I do not have a 20mm Manual, but I am sure someone on the board does.





Hey there again Frank.

Thanks for supplying me with the above info. I don't need the manual to do what I was thinking of with the stern mounted 20 mm on one of my RC boats.

I think this will look quite awesome if I can just get my ideas built to look on the model like they look in my mind's eye.

Cheers from Peter

"Give me a faster PT boat for I'd like to get out of harm's way!"

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PeterTareBuilder

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of PeterTareBuilder  Posted on: Apr 20, 2011 - 12:26pm
Frank (and others).

Here's a link to an on-line manual about the 20 mm. I don't know if it's the manual you were thinking of.

http://www.hnsa.org/doc/gun20mm/index.htm

Cheers from Peter

"Give me a faster PT boat for I'd like to get out of harm's way!"

Total Posts: 494 | Joined: Jun 24, 2008 - 5:59pm | IP Logged

Drew Cook

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Drew Cook  Posted on: Apr 20, 2011 - 1:33pm
Although you don't see a whole lot of the shell bags on PT's 20mm guns, they'd make a nice little added detail on a model, if accurately rendered.


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Frank J Andruss Sr

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Frank J Andruss Sr   Send Email To Frank J Andruss Sr Posted on: Apr 20, 2011 - 5:02pm
Drew

I agree with you there. I just had a very nice 1/24 scale PT 109 model donated to my Exhibit. The guy who built the boat did a very nice job, although some items need to be added to make her correct. I will bring her to Stan's for conversion, and one of the items to be redone will be the 20mm. I will probably have Stan add the shell bag, as I too think it will really add to the boat.


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Will Day

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Will Day   Send Email To Will Day Posted on: Apr 20, 2011 - 6:14pm
Anyone know where this was taken?




Will

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  Jerry Gilmartin

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Jerry Gilmartin   Send Email To Jerry Gilmartin Posted on: Apr 20, 2011 - 7:03pm
Will,
It looks like it was taken near the stern of an Elco PT boat! Har Har! Jerry

Jerry Gilmartin

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Will Day

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Will Day   Send Email To Will Day Posted on: Apr 20, 2011 - 11:02pm
Just the kind of astute observation I would expect from a Higgins guy.....

Will

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TED WALTHER

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of TED WALTHER   Send Email To TED WALTHER Posted on: Apr 21, 2011 - 12:02pm
Will;
Looks like Toboga in backround. As for the boat, possibly a RON 18, 21, 24, or RON 25 boat, I remember seeing photos of this series with tubes and this type of "soft" stern mount 20mm, I believe they used this because they "Got the word" and knew they would be getting the 40mm's soon after arrival in the war zone.
take care,
TED




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