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Posted: Tue Dec 12, 2006 7:20 pm
by judgment_arms
What the heck are you talking about? By high powered pellet gun do you mean a pre-charge pneumatic .50cal dragon slyer? Because my Gamo shadow 1000 won’t drop a coon at much past 20 yards.
Well good for you, so I’m wrong about the .223. I already said I don’t like the AR15/M16, or the round.
You know what a 30-06 does to a watermelon at 1000yards? No more melon.
But what the heck does the .223 have to do with a paintball rifle?

You know my idea will work but you don’t want to admit it because that means you were wrong, so you change the subject.

Posted: Thu Dec 14, 2006 4:22 am
by joannaardway
The AK47 doesn't jam - I give it that. It's damned accurate in single-fire mode.

Put it to full-auto, and you couldn't hit a large van at 10 yards - I've seen it done in various TV programmes (you might find the clip somewhere on the internet)

I tend to find that most guns don't jam if you use them properly. I've used things that are supposed to jam all the time. Cleaning and using them properly, I've never ever had one jam on me.

I didn't spend hours looking for pipe. I just retain all the info I read in various topics across the spudding world, and recall it on cue.

.68 hydraulic tubing is fairly common, although it is metal.

About D_Hall - He's a member of Spudtech - an engineer of sorts. Wrote GGDT.

Rifle the goddamn pipe if you want to. I'm just trying to suggest more practical solutions.

Finally, after further thought, I think a possible reason that you never see real firearms with spin inducers might be that the effect will only work at subsonic speeds (or so I read somewhere - not sure it's true)

Posted: Thu Dec 14, 2006 5:47 am
by Scope
I hate to shoot down your pipe idea... but paintballs are mostly around .689ish caliber. They shift from product to product but few, if any at all, are .68 cal. and the most important thing in paintball for accuracy is a good paint/bore match... if you where to make this gun get a barrel kit. that way you can adjust the I.D. of your pipe.

Posted: Thu Dec 14, 2006 12:04 pm
by judgment_arms
Thank you all for the information that someday I’m sure I’ll find useful. Rifling my be less practical, but half the reason for doing this is to see if I can.
I fell like a doorknob for forgetting who D_Hall was and forgetting about the .68 hydraulic tubing.
You got me again the AK47 is inaccurate in full-auto, I forgot I don’t study up on the modern military weaponry, my area of interest is pree-1900s more particularly the late 1700s through the 1800s i.e. the guns of the old west. now then if nobody got it I’m saying “sorry I was wrong about the AK47, M16A2, and a few other things.” It’s 11 days till Christmas so, “tis’ the season to be jolly”

Know if you’d be so kind, I’ve requested help on other parts of my air rifle.

As a closing thought:
God rest ye marry gentlemen let nothing ye dismay! Remember Christ are savior was born on Christmas day! To save us all from Satan’s power for we had gone astray! Oh, good tidings of comfort and joy, tidings of comfort and joy!
- first verse of “god rest ye marry gentlemen”

Posted: Fri Dec 15, 2006 4:29 am
by joannaardway
Good point - I do a lot of things just to see if I can...

"I wonder if I can shoot a grape through that fence?"

Posted: Fri Dec 15, 2006 7:26 am
by Recruit
joannaardway wrote:Good point - I do a lot of things just to see if I can...

"I wonder if I can shoot a grape through that fence?"
Frozen or unfrozen Joan?

Posted: Fri Dec 15, 2006 8:04 am
by joannaardway
Either really - but I tend to find that the unfrozen ones can get destroyed in the barrel by higher pressures.

I was messing around with my brother the other day, and he was putting serious dents in steel plate with frozen grapes.

Posted: Fri Dec 15, 2006 8:16 pm
by judgment_arms
UPDATE:
Before I make the revolving rifle I thought it would be a good idea to make a smaller, single shot, version with an 18inch. And while I’m at it I’d see if it even needs to be rifled by comparing it to a smoothbore barrel of the same length.
Does anybody know what the specific gravity of a paintball is?

Now then, here is the plan for the biggin,
It is now going to be a LeMat (google it) style long arm

-Barrel: ¾ inch SCH 40 PVC, rifled, rate of twist =: 1 in 41, length = 36 inches.
-Low pressure/main chamber: 12-14 inches of 1 inch SCH40 PVC.
-Valve: undecided, most likely a chamber sealing piston tee valve.
-High pressure reservoir: approximately 20 inches of 2 inch SCH40 PVC, 12inches of which is used as the stock the other 8inches are under the barrel, connected by breaded hose.
-*new* 1.5inch by 18inch under-barrel scatter-gun fired by a 1inch modded sprinkler valve.

Picture is a basic sketch of the workings of the model 001(the name of the revolving rifle)

Questions, comments, and ideas are welcome.

Posted: Sun Dec 17, 2006 2:36 pm
by joannaardway
The paintballs I have weigh about 3.4 grams. (Some weigh more I'm told), and have a diameter of 17.27 mm-ish.

That works out as a volume of 2.7 cm^3
Dividing: 3.4/2.7 = 1.26 g/cm^3

I assume those aren't the units you need - so go to google and type: "1.26 grams per cc = ? xxx" where xxx is your desired unit. The automatic calculator will do the conversion for you.

Posted: Sun Dec 17, 2006 4:47 pm
by judgment_arms
Would the answer to that be the specific gravity? Math is not exactly my favorite subject.
I googled it like you said but it didn’t work… I’ve got a friend who is good at math, I’ll ask him to convert it. Thanks for the info.

Posted: Mon Dec 18, 2006 6:33 am
by joannaardway
Yes. "Specfic xxx" means the "amount of xxx per unit volume" - so "density" in this case.

I checked the google thing with "1.27 g/cm^3 = ? oz per cubic inch", and a couple of others and it was fine.

Posted: Mon Dec 18, 2006 1:51 pm
by judgment_arms
*slaps head on wall* it worked this time, but it didn’t all the other times I tried it.
Can’t even get google to work, I’ve got to be three rounds short of a full magazine
Thanks again.

I just found out that the Greenhill formula is for lead or lead core bullets, and doesn’t work on really light weight projectiles. (i.e. paintballs) I don’t think it works on the all copper military bullets. I calculated it any way and it said I needed a rate of twist of 1 in 102inches! The Greenhill formula also doesn’t use a specific velocity (150 if it’s lower than 2800fps, 180 if higher than 2800fps) so know I’m confused witch do I use 1 in 41 or 1 in 102? My gut tells me to try both and see witch is more accurate, but I figured I’d ask what y’all think, since there are people on here who are obviously more learned than I. …my head hurts now… I’ve obviously got a lot of research to do before I start work.
Great