Improving the Barrel (PDF File)

[Hubb]

Dear fellow Spudders.

I've been doing quite a bit of experimenting and research on barrels and barrel systems. While most of my research has been involved with paintball barrels, I couldn't help to notice that a lot of the principles are involved with spudgun barrels.

A lot of the data in this book is common knowledge, especially to experienced spudgunners. It demonstrates several techniques on barrel improvements and upgrades and also includes a list of commonly used projectiles with their respective barrels.

While I do have experiences with most of the techniques in the book, none of it is my own. If I have used an image from your work, congratulations (it is Hubb worthy ). I have simply taken the information found across the web and put it into one place.

Now, I share it with you guys.

Improving the Barrel
Barrel Calculators

[c11man]

great book.

only suggestion is to expand the section on different barrels for different ammo

[MountainousDew]

Yeah he could, or he could just give the address to the "Ammo Ideas" thread here on SpudFiles.
I too have a suggestion for the Ammo section, with the 12 oz Soda Cans, you said 3" sheathed into 3" pipe, which works, I guess but there is also 2.5 SDR 26 pipe... Just a suggestion though.

Other than that, I thank you for writing this up... I just skimmed over it but I think it is amazing!

[Hubb]

I considered putting in the 2.5" thinwalled pipe, but several tings kept me from doing that. This sort of pipe is a lot harder to obtain compared to a piece of 3" pipe. Also, because it is a thin pipe, it will need to be sleeved, and I am not familiar with a sleeving pipe for it.

[MountainousDew]

Yeah, I guess you're right...
Also, how hard is it to sheathe 3" pipe into itself?

[Hubb]

About as hard as any other sleeving project. Pretty freakin' aggravating. But watching a full can of soda smack a brick wall and explode may just be worth it.

[MountainousDew]

Yeah, I'm going to make a Soda Can Mortar, and I can't decide weather to use 2.5 SDR 26 or sheathing 3" pipe...
Any ideas?

[c11man]

use sdr 26. just order from gort and with a short barrel you wont have to worry about barrel flex

[Technician1002]

I considered putting in the 2.5" thinwalled pipe, but several tings kept me from doing that. This sort of pipe is a lot harder to obtain compared to a piece of 3" pipe. Also, because it is a thin pipe, it will need to be sleeved, and I am not familiar with a sleeving pipe for it.

Un-sleeved SDR26 works fine. I tested a 7 foot length un-sleeved with no problems.

But watching a full can of soda smack a brick wall and explode may just be worth it.

Yes, the splat is impressive.
Much of the side of the can is tiny shrapnel.
Tested on my 700 cu in cannon with the 2 inch valve.

[john bunsenburner]

Great write up, lots of pictures and diarams easily comprehendable all in all perfect, however it fixes(and I know i have pointed this out to you before) mostly on PVC barrels, perhaps a few things such as rifelign and polishing the barrel could be adapted to metal barrels, and would be very valuable for those that are using metal. I for example would be very happy if i had instructions on rifelign my copper and alli barrels.

[inonickname]

Very nice guide! Shamefully for me it's highly PVC oriented, and probably won't be a mass amount of good to me (oh well, the breeches I suppose, but my next gun will be a highly chaos style bolt action..). It's a bit hard to cut riflings into an anodized 1616 aluminum barrel of around 5mm.. (I was glad when I opened it up, it was anodized on the inside and out!)

Great guide though.. Some of the pictures were sourced from elsewhere but better than nothing of course!

Brilliant for the newer people or the ones who still dabble in PVC and potatoes..

[mark.f]

Hmmm... interesting write-up. The only things I would have to say are:

1.) Typos. I could go back and find them all again, but they should stick out upon a second inspection. Not misspellings, but things like "you" instead of "your", missing words, etc.

2.) Airsoft and steel BB's will fit into more than just ready-made airsoft and .177 caliber barrels. Airsoft BB's fit into 5/16" brake line, IIRC, and steel BB's fit into 1/4" steel hydraulic tubing (brake line) very well.

3.) Paintballs fit superbly into 3/4" aluminum hydraulic tubing, which has a 0.68" inside diameter. This can be found in specialty shops or on McMaster, and is the sole reason paintballs were made to .68 caliber in the first place.

4.) Sabots can be discussed a bit more. Like how some are designed to break away smoothly from the projectile, and how firing a smaller, denser projectile can help with penetration.

Good job, other than that. The information on rifling was interesting, and should be helpful. Somebody on the UKSGC forums posted a method of grinding a cutting die from a bolt head which would cut and rotate automatically, as well, here. Might want to look into that as an addition for v1.02-3.3-a7.

[Hubb]

Thanks, guys. Suggestions are noted. I guess I should have put more detail in metal barrels. I'll let you guys know when it's updated.

[inonickname]

That one of the bolt head is sweet mark! I might try something similar from hardened steel rod and test it on a piece of pipe the same size as my barrel.. Not keen on scratching the nice red ano 8)

[jimmy101]

Nice job hubb017. Perhaps add as a page to the spud wiki and reference yourself as the orignator?