SpudFiles

Want to tell us how you will do it again in this thread?


With alli tubign the walls are ussually thicker, so i think woder and deeper grooves may be possible...

Ragnarok wrote:

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.

I said to sleeve it and cut the rifling in for max accuracy.

john bunsenburner wrote:Want to tell us how you will do it again in this thread?

Well, I've said it quite a few times before. But anyway, I'm working on an idea to cut lands using a piece of 20mm OD pipe, which will then get soldered inside the 20.2-20.3mm ID copper I use.
The actual soldering will be tricky, but I've figured a way to go about it.

I've yet to confirm the twist I'll use for the test barrel, but I guess around 10 rad m^-1 is likely.

Yes the soldering does sound hard. Why not thread the entire lengths of both pipe, and just screw it in? Sounds easier than soldering.

hah a suuup 8)

john bunsenburner wrote:Sounds easier than soldering.

Threading over a metre of barrel easier than soldering? I doubt it.

Anyway, it can't possibly work. The lands will be 6 individual spirals, so half the surface area of the inside barrel will still be exposed. If I had threaded the outer layer of the barrel, then the threads will at worst be rubbing against the projectile (the specifics will vary*), and at best causing flow restriction.

*Depending on the projectile and "chambering" it'll swage some projectiles, and obturate others.

Also, threading weakens the pipe.

Alright, good luck solderign over a meter of pipe!

The soldering doesn't need to be done along the whole length at the same time. With the way I'm doing it, I can just start at one end and move down.

Alternatively, if I'm feeling in a silly mood, I'll just set up the whole barrel as a pulse jet chamber and simultaneously solder the whole length.