copper rifling idea....

[lockmanslammin]

I need to bounce an idea off of you guys. my barrel is 1/2" type l copper.
I have been thinking of trying to rifle it. Problem is that This gun is being used at high pressure, so any rifling would weaken the tube, unless it were very shallow. I just had an idea this morning though and I was wondering what you guys thought of it.

Not to long ago I read an idea for using a wooden dowel with a spiral of tape around it to use as a visual aid in drawing the rifling down the barrel with some even consistency.

I was thinking of using that idea and changing the cutting part at the end.
Imagine a sanding drum for a dremel. It would be something like that, then instead of a sanding drum I would wrap some heavy grit sand paper, like 50 or 60 around the drum, put it at the breach, tighten the "drum" and pull it through. This would keep the rifling shallow, but put a ton of grooves down the barrel.

What do you think?

Lock

[judgment_arms]

I think you groves will be too shallow and the projectile will just blow straight through them.

That’s the main reason I don’t rifle copper, I normally make groves as deep as copper is thick.

[jimmy101]

You will have to pull the dremel through the barrel at about the same speed as the ammo goes through the barrel.

So, it'll work great if you can figure out how to get your Dremel moving at say 500 FPS.

Most rifled barrel only have a turn or two of the rifling for the entire length of the barrel.

[psycix]

He doesnt use a dremel jimmy.
He said, using a sanding drum LIKE one on a dremel.


But I also dont think it wil work lock.
The projectile doesnt get much grip on a rifled-sanded barrel.
It just gives extra friction.

[SpudFarm]

you know those drills the dudes use to make holes in walls for wires? long and not to sharp curve. mabe you can use them in some sort of way?

or mabe make a mold to put in your barrel with the grooves on the outside like a bullet after it have passed in the barrel. then you slide the mold in the barrel and fill the grooves with solder. really hard to explain.

that was an idea that popped out of me.. if you feel any interest just let me know and i can think out a way to do this.

[psycix]

The mold idea is interesting spudfarm.
Do you fill the whole space up with solder EXEPT for the grooves, so you get some sort of grooved solder sleeve on the inside.
Or are there grooves in the mold and then fill those with solder so you get "the opposite of grooves" into the barrel? Wich might also work.


Groovy!

[SpudFarm]

haha i meant filling the grooves so it is not grooves in there but "out dents" but it is up to the builder..

i think i am going to do that

[bluerussetboy]

.....

or mabe make a mold to put in your barrel with the grooves on the outside like a bullet after it have passed in the barrel. then you slide the mold in the barrel and fill the grooves with solder. really hard to explain.

...

What your trying to explain is actually called button rifling. It actually is a fairly popular way to rifle barrels. With button rifling you are able to cut all the grooves and lands with one pass, with standard cut rifling you have to make several passes to cut all the grooves unless you have a progressive broaching bit(broach rifling).

Oops, I re-read your comments a few more times and realized you are actually talking about flow forming, another type of rifling that a Turkish company has been playing with. Google

[psycix]

I think that this "flow forming rifling" would be able give enormous spin on the projectile, because the projectile can really fit on the "rails".
There wont be much groove (in this case outdent)-hopping.

I think that the largest con of this typ of rifling is that it will probably wear out very fast. Might even break on the first shot if not done properly.

[SpudFarm]

i will flux the inside of the barrel and warm it up to almost the melting point (mabe grind a bit like when you spray paint) and ad silver solder.

only one way to find this out.. bet it is not suitable in small bores, high pressure and heavy projectile.

well i am going to get one of the "rods" from Larda when i get money after the hybrid. if i get more money i order another barrel from him and rifle it for lead slugs cast in a rifled piece of the barrel so i have grooves on the slug.

[psycix]

The rifling of both the barrel and the projectile should be perfect, if its not, you might get problems with jamming, and thus breaking off the rifling.

[SpudFarm]

if i first destroy the rifling on the hybrid in the middle of the barrel i send a steel slugg through it to take it all away and then ad the barrel to the barrel i already have to get more velocity on heavy projectiles

[nivekatoz]

You could serch for red brass water pipe on the internet..Thats what I used on my gun. Thats stuff is thick and smooth and seamless on the inside..A perfect blank canvas to put rifling and still be thick enough for safety. I think you could find thick aluminum or brass tube also..Its a little bit of a hassel unlike just running down to the hardwear store, but with a bit of research you can exactly what you need and want to make the perfect gun..

[psycix]

Or use a sleeved barrel to get an extra thick wall.

[cdheller]

I'm not sure how this would work out but,
polygonally rifling the copper by hammering it to fit a 5 or 6 sided die inside the barrel might get a full wall thickness and provide a better projectile grip.

3/8" nuts work for 1/2 " emt electrical conduit well enough to make a cheap long socket to adjust allthread nuts,

just a thought