Page 3 of 4
Posted: Thu Jan 24, 2008 4:27 pm
by DYI
If it would be possible for you to rifle steel pipe, I could get 2" seamless steel for a barrel, which would likely be cheaper than copper anyway.
Posted: Thu Jan 24, 2008 6:32 pm
by judgment_arms
I don’t know about steel… I suppose I could use some high carbon high temper steel to cut it, or maybe a steel cutting drill bit… I’m not going to say if I can or can’t or if there’s even a chance that I could until I have done more research… sorry.
On the other hand, that sounds like it would make a good barrel, how thick are the walls?
Posted: Thu Jan 24, 2008 6:47 pm
by DYI
With a bit more research, I discovered that steel would cost about the same as copper. The advantage is that the walls would be thicker, and with pressures theoretically in excess of 4kpsi, that's always a good thing.
I'll probably just stick with smoothbore though. Construction of this can't start until March anyway.
Posted: Thu Jan 24, 2008 9:17 pm
by Ragnarok
I think it's of fairly high priority that we find out how fast you can actually spin a potato.
I've done some thinking, and I can now work out the forces trying to spin a spud to bits if I know it's spin speed and diameter. Problem is, I don't know what forces said spud can take. I need to go down to the university labs with a potato and put it in their load testing machine...

Posted: Fri Jan 25, 2008 3:49 am
by zephir
I might need a rifled barrel. I'm build an hybrid (if you can call it that), I don't know whether it'll be benefical, I need 1/2" copper pipe, about 26" of it, my main projectiles will be AA batteries and front-jacketed lead slugs.
The AA batteries should fit well in the 1/2" copper pipe, it fits well in the ones I have, don't know about you, though. The pipe needs to have thick walls, one end have a lightly larger diameter than the other, .59" inner diameter going in about 1.15 inches.
The lead projectiels I plan on using will be jackets in the front half, the back will not. It would adapt to the rifling better. They will be slightly wider than the AA batteries, and about 3 inches long.
Posted: Fri Jan 25, 2008 7:04 am
by jackssmirkingrevenge
It's important to note that rifling will not affect hard projectiles like marbles, in order to be effective the projectile mus be soft (or have a soft ring/exterior) that the lands can bite into in order to impart spin.
For example, for an AA battery, it will need to be well wrapped in duct tape in order to be spun. Also, a battery is very long in relation to its diameter meaning it would need a very fast twist rate to stabilise it, which would probably be unrealistic for spudguns.
Posted: Fri Jan 25, 2008 12:36 pm
by judgment_arms
Zephir, how long are your lead slugs?
Jack (you never really said if it’s okay that I call you that), I believe I already said that hard projectiles would need to be wadded, or was that in the other thread?
As for the rate of twist, the old Greenhill formula says 1 in 12 to stabilize a AA, and its bean my experience that the updated one gives a significantly higher rate of twist.
Attention everybody interested in purchasing a rifled barrel:
Do to the fact that everybody needs/wants a different bore size with a different rate of twist, I’ve decided that instead of selling a few particular sizes I’ll make custom for each person. Note that that will mean barrels will be slightly more expensive, prices are as follows:
Pipe:
Note: I will not be rifling copper tubing any bigger than 1 inch
2” will be $2.75 U.S. a foot for PVC $4.00 a foot for SCH80 PVC
1 ½” will be $2.00 U.S. a foot for PVC
1” will be $1.50 U.S. a foot for PVC $17.75 U.S. a foot for type L copper
¾” will be $1.25 U.S. a foot for PVC $9.50 U.S. a foot for type L copper
½” will be $1.00 U.S. a foot for PVC $7.00 U.S. a foot for type L copper
Rate of twists currently offered:
1 in 14 (300 fps paintballs)
1 in 60 (Stabilizing NERFs, potatos)
Custom Runs will be an additional $10.00 U.S.*
You pay shipping.
*If I do not have a blank (previously referred to as a “die”) that matches the rate of twist you want I’ll suggest one close and ask if that will suit, if not, or if there’s not one close enough, I’ll have to make a new blank which will cost you an additional $10.00 U.S.
Sorry for the inconvenience, but I have to turn a profit some how.
NOTE: if before I start filling orders I get enough people (5-10 depending on bore size) that want the same Rate of Twist I may drop the custom run fee, also if two or more people (but not enough to drop the fee) want the same rate of twist the price of the new blank will be split up between them.
I’m going to start taking orders now but it’ll be most likely be after April before I can get stuff together to fill your orders
If you’re still interested PM or E-Mail me, or make a post, with what caliber, what type of pipe, and what you want it to shoot at what velocity; i.e. 1 ½” inch PVC rifled for potato slugs 5 inches long at 300fps.
questions? PM me or make a post.
Thanks!
Posted: Fri Jan 25, 2008 1:08 pm
by jackssmirkingrevenge
judgment_arms wrote:Jack (you never really said if it’s okay that I call you that), I believe I already said that hard projectiles would need to be wadded, or was that in the other thread?
As for the rate of twist, the old Greenhill formula says 1 in 12 to stabilize a AA, and its bean my experience that the updated one gives a significantly higher rate of twist.
Jack is fine
I must have missed that, just thought I'd point it out for those who weren't aware that it takes a little more than simply rifling your barrel to get gyroscopically stable projectiles.
Posted: Fri Apr 11, 2008 11:19 pm
by judgment_arms
Attention:
With the rising price of crude oil, the price of both PVC pipe and the gas to go get it has gone up, it saddens me to say that I’ll be charging an extra $0.25 per foot, sorry y’all…
In addition, the first five people to place orders will get 10% off their total price.
People who have placed orders:
Socoj2, 5 feet of 2 inch SCH 80 with a rate-of-twist of 1-in-60
I will hopefully begin filling orders within the month.
Current prices and rate-of-twists are in my previous post.
Posted: Tue Apr 22, 2008 3:31 am
by Ultimate Weapon
Hey could you rifle 1/2" CPVC? It's only slightly smaller than sch40 1/2" PVC.
Posted: Tue Apr 22, 2008 7:31 am
by judgment_arms
I ain’t to sure, I’ll have to see if I can find a rod that’ll fit in 1/2 CPVC.
How long of a barrel were you looking for?
Posted: Tue Apr 22, 2008 9:38 am
by PCGUY
If you are really to the point of selling these, then you need to make a new topic in classifieds along with pictures of the product and your SpudFiles user name in the photos.
Posted: Tue Apr 22, 2008 9:57 pm
by judgment_arms
PCGUY wrote:If you are really to the point of selling these, then you need to make a new topic in classifieds along with pictures of the product and your SpudFiles user name in the photos.
Well, I’m not quite to the point of selling them yet, I still need to finish me rifling machine, which requires money that’ll, hopefully, have in a week or so.
But as soon as I get the rifling machine up and running I’ll put a thread in the Classifieds section.
On that note, how much do I owe you per sale?
For those interested in a rifled barrel I am indeed taking orders right now.
Posted: Wed Apr 23, 2008 4:51 am
by Ultimate Weapon
In that case. I would like to order 2' of rifled 1/2" CPVC. It will be shooting 2 inch foam darts at around 200 fps.
Posted: Wed Apr 23, 2008 5:13 am
by ghostman01
can some one please link me to somthing that shows me how to rifle a barrel please