Rifled copper barrel

Potatoes last one shot, so build reusable! Discuss ammo designs and ideas. Tough to find cannon part or questions? Ask here!
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Ragnarok
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Sat Aug 16, 2008 4:09 pm

MaxuS the 2nd wrote::lol: Indeed, you will be made fun of.
Right! If that's the way you want it -- Cardinal! Poke him with the fun!

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Confess! Confess! Confess!

...Ahem.
That..Is a total moron.
Well to be fair, he was in charge of the economy for ten years of nothing but growth - not a single financial quarter was a loss. That had never been done before, and is unlikely to be repeated again soon.
Of course, he's made a lot of bad decisions since becoming PM, and the economy has now gone down the wotsit...

But enough of cluttering the thread with Monty Python references and bad jokes about Gordon Brown.
Does that thing kinda look like a big cat to you?
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jimmy101
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Sat Aug 16, 2008 5:30 pm

Pretty impressive. I'm surprised that grooves that shallow actually work on a spud.

Try hanging up sheets of news paper every 20 feet or so and shooting through them all at once. It's possible, though probably not very likely, that the spud is still tumbling but you got lucky and at that range it happens to be back to "nose forward" flight (or perhaps it's done n*180<sup>o</sup> tumbles).
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SpudFarm
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Sat Aug 16, 2008 5:47 pm

i rifled my marble barrel like that right now.. i did so deep rifling that it almost cut through the barrel and it works..

it has like 100 turns through the barrel to
:oops:
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- A spud gun insurance.
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al-xg
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Sun Aug 17, 2008 4:43 am

I might try that if I cant find something to hang the sheets from :?
Im quite sure thay didn't tumble, just because the canon I used isn't very powerful and I can see the flight of the spud (sounds like a crappy film title ;)).

I did try putting a small nail in the nose of one of the slugs and It did left a mark, but I guess that is cheating as its putting its center of gravity forward and might have flown straight anyway.
Also It might leave a mark when flying backwards as the potato splaters on impact. :roll:

Il try filming a few shots.

Ooh, thats maybe a bit too much ?:) or you have a really long barrel ?
The prejectiles must be spinning very fast.
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Ragnarok
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Sun Aug 17, 2008 5:01 am

al-xg wrote:I can see the flight of the spud (sounds like a crappy film title ;)).
*Puts on the Wagner*.
Dudalum, Dudalum, Dum dudah dah dum, dum dudah dah dum, dum dahudar dahhhh...

:D

Yeah, I chose Ride of The Valkyries over Flight of the Bumblebee, but Flight of the Bumblebee can't be put in onomatopœia so easily.

The prejectiles must be spinning very fast.
I'd be rather surprised if anything gripped rifling that steep at all - I'd more expect it to jump over the grooves.

Over rifling is not usually a good thing, usually a projectile that is spun too fast develops flight eccentricities.
Does that thing kinda look like a big cat to you?
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CasinoVanart
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Sun Aug 17, 2008 5:08 am

Ragnarok wrote:
al-xg wrote:I can see the flight of the spud (sounds like a crappy film title ;)).
*Puts on the Wagner*.
Dudalum, Dudalum, Dum dudah dah dum, dum dudah dah dum, dum dahudar dahhhh...

:D

Yeah, I chose Ride of The Valkyries over Flight of the Bumblebee, but Flight of the Bumblebee can't be put in onomatopœia so easily.

The prejectiles must be spinning very fast.
I'd be rather surprised if anything gripped rifling that steep at all - I'd more expect it to jump over the grooves.

Over rifling is not usually a good thing, usually a projectile that is spun too fast develops flight eccentricities.
You should change your name then Rag, "OverRifle", has a nice ring to it!
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SpudFarm
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Sun Aug 17, 2008 5:17 am

al-xg wrote: Ooh, thats maybe a bit too much ?:) or you have a really long barrel ?
The prejectiles must be spinning very fast.
it turned out like that because i have to adjust the speed of the drill up to get it to turn and then it suddenly started eating its way throug on about 500rpm..

they do rip themself through the rifing but it apears that it get some spin since i get round holes from really long slugs..

the barrel is about 1.6m since i cut of piecec to practice on
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Ragnarok
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Sun Aug 17, 2008 5:17 am

CasinoVanart wrote:You should change your name then Rag, "OverRifle", has a nice ring to it!
Who said I had flight eccentricities? :?

Actually, I'll be honest, I'm not keen on flying or heights (which isn't very useful for a stage techie who has to spend lots of time up scaff towers and ladders :roll:) - would that count as a flight eccentricity?:P
Does that thing kinda look like a big cat to you?
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al-xg
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Sun Aug 17, 2008 5:24 am

Oh, right, I didn't use a drill when rifling my barrel as the tool's ridges set the rotation.

I pulled mine through and left the turning to the tool, intead of turning it and leaving the pulling to the tool :)


@ Rag, mmm might just not be enough, on the other hand something like this http://www.youtube.com/watch?v=h2sI8vIJQY8... :roll:
You lucky bastard !
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SpudFarm
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Sun Aug 17, 2008 5:27 am

i know but i had no way of pulling that far while holding the barrel stable when i was 2m from the barrel :D

i will give it one more try and lay some effort into it when i know that it works.
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nakarti
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Wed Oct 21, 2009 4:32 pm

String or cable to the end of the rifler and winch it through instead of push it through?

I now want to do inward-groove rifling on my next gun, but I have to build smoothbore first!
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Brian the brain
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Fri Oct 23, 2009 4:53 pm

Yo Psycix..see how close I was?!?!?!

All I had to do was apply tape to prevent the head from digging in!!
And to think I was so known as a kid to use scotch tape for everything my folks gave me a nick name
Plakband Japie
Wich translates to something like Scotch Tape Jake...
I'll rebuild my own method ( deeper grooves) soon.
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Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
ThegunGuy
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Fri Oct 23, 2009 11:31 pm

Good job on that it looks great. The 1:8 twist on the rifling sounds about perfect. But you will probably need much deeper rifling for it to be accurate. The little tiny lines on that will slip a lot unless you are using over sized projectiles that are breach loaded. If you have ever seen the rifling in a muzzle loader rifle it has very deep rifling to catch hold of the projectile. The lands are as big as the grooves in a lot of the muzzle loaders I have seen and are very deep some are almost 1/16 of an inch deep. Pretty much all you need to do is widen the teeth on the rifling tool and make them sharper on the edges so it will shave metal off of the inside of the barrel. But you probably would have to sleeve the barrel with something to make it strong enough to withstand higher pressure.
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john bunsenburner
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Sat Oct 24, 2009 7:16 am

Perhaps doing this with alli woudl be easier and would give better results.

And i agree to making the grooves deeper and wider.
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Ragnarok
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Sat Oct 24, 2009 7:41 am

john bunsenburner wrote:I agree to making the grooves deeper and wider.
I don't. Copper already has very thin walls, so a groove can only be so deep without seriously compromising strength.

Like I have said for no short length of time, if I were rifling copper by cutting grooves , I'd pretty much insist on sleeving it.
Still, that's not the way I'm planning on doing it...
Does that thing kinda look like a big cat to you?
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