Pump action shotgun

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YEAHADD16
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Wed Feb 04, 2009 3:50 pm

Im working on a pump action shotgun that holds about 4 to 6 rounds, I finished the magazine recently, but the barrel and ejector slot I am going to have trouble. Anyone's input will be greatly appreciated
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Hubb
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Wed Feb 04, 2009 5:02 pm

Dues ex machina...<is that spelled right?

Do a search. I can't remember who made it, but it is what you're looking for. There are other magazine fed stuff out there, but that's pretty good.

Another option is the famous Boltsniper BS-5. It's for Nerf, but it could be adopted.

Edit: I'm feeling genrous today. I did the search for you.
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dudeman508
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Wed Feb 04, 2009 9:34 pm

Dues ex machina...<is that spelled right?
http://www.spudfiles.com/forums/deus-ex ... t8418.html

Thats it :D
the other post on it can be found at the bottom of the post i gave you the link for.
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YEAHADD16
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Thu Feb 05, 2009 3:43 pm

thanks for the links, lots of great info, but i am pretty much replicating how an actual pump action shotgun works
http://science.howstuffworks.com/shotgun5.htm
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sputnick
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Thu Feb 05, 2009 5:26 pm

Well, for the ejector, you would need to be able to pull back the shell somehow, so assuming the ejector port is on the right side, you need a spring powered hook on the bolt, again on the right of the bolt, that pulls it back, and then you need a notch cut out of the left side of the bolt, where a spring loaded arm can go in behind the shell, and push it out while you cock the gun.

There's an old fashioned video on you tube showing the internals of real guns, but the ejector system would be of interest to you, I will try to find it and get back to you :)

After much searching, I found them :D

[youtube][/youtube]

[youtube][/youtube]
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SEAKING9006
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Thu Feb 05, 2009 7:44 pm

I want one of those models. 0_0
Completed projects:
CA1 SMSS Basic Inline
CA3 PDAB Airburst Cannon

Current Project: Bolt action rifle (25x140mm + 1in shot)
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sputnick
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Thu Feb 05, 2009 7:48 pm

It's a really good movie no? I love it, so simple, yet it gives such simple and clear demonstrations... truly a great video. You can't get that level of understanding with a computer model, nothing like the classics :D
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iknowmy3tables
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Thu Feb 05, 2009 8:08 pm

dudeman508 wrote:
Dues ex machina...<is that spelled right?
http://www.spudfiles.com/forums/deus-ex ... t8418.html

Thats it :D
the other post on it can be found at the bottom of the post i gave you the link for.
That's me, so you said you made a magazine, but what shells are you going to use. Proper ejection is going to be depend on the design of the shells which will probably be affect the diameter of the shells which will affect the design of your magazine. This is why you should make sure you got the entire design down before you start building.

do you have a lathe? it would be handy for cutting grooves to act as a rim for extraction. you could use friction like my gun which can be easy but has it's downsides, or you could use a rim and extractor system like the one used on real guns and these homemade nerf guns which as you can see is effective but can get kinda complicated
http://www.boltsniper.com/BS-5/BS5.htm
http://www.boltsniper.com/BS-8/BS8.htm


edit: also looking at the diagrams on how stuff works I can clearly see that there is not enough detail to make your pump action system and there are parts you will probably find too precise a delicate. my recomendation is to scratch the carrier dog and make a sliding-cam-like mechanism so the carrier only lowers when the bolt is pulled all the way back. second the mechanism that is not included in those diagrams is the thing that keeps the shells from popping out when the carrier is raised; I would propose a leaf spring tab on the bottom of the magazine opening aligned and adjusted so when carrier is lowered it would push the tab out of the way
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YEAHADD16
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Fri Feb 06, 2009 3:26 pm

thanks for all the input. I am definitely not going to replicate every piece, but the videos and other spudfiles gave me some great ideas. I'm still working on the prototype, I found out that the spring I am using may be too strong and will have to find another one. Thanks again for all the input.
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