SpudFiles

noname wrote:
I'm on a college student budget here,

Do colleges have weapon policies, also do you just build this in your dorm room... looks huge lol

Well I just finished fixing the launcher up. I should be able to test fire tomorrow or Monday. Fingers crossed for no rain and proper ignition!

sagthegreat wrote: Do colleges have weapon policies, also do you just build this in your dorm room... looks huge lol

I built it at home over winter break. It's definitely illegal to have in the dorms, that's why it generally lives in my friend's apartment/car.

So I finally got around to test firing golf balls this weekend! I found a pretty good area out in the middle of nowhere and the owners don't seem to care. The balls go really far really fast, I really can't judge velocity or distance at all.
Tried to take it up to 6x but the foil burst discs creased just like the soda cans, leaking all the fuel out the barrel. The coolest shot was a 4x shot with three golf balls loaded, it actually gave it some kick.
I seem to have trouble with ball stability or something; the balls sometimes hook in any random direction. Any suggestions?

In a smooth bore, any spherical projectile will have a tendency to curve. Whatever inside edge of the barrel it contacts is going to impart spin, and the random nature of burst disks rupturing will cause this phenomenon to be rather unpredictable... In paintball, there are such things as "flatline barrels" that are actually curved slightly downward, causing the paintball to be constantly contacting the top of the barrel, which imparts backspin on the ball and acts as a hop up. I've never seen anything done like this in spudding, let alone a hybrid...

However, if you take a look at the Hubb Library, you will find a section about homemade hop up, done by curving the tip of the barrel slightly down. I did this on my pneumatic golf ball gun, which you can see in my signature... The piece of pipe that I angled down eventually broke from being repeatedly bashed by high speed golf balls.

Perhaps you could implement a similar concept on your gun, but that would tailor your barrel specifically to spherical projectiles, and it gets expensive to fire a bunch of golf balls all the time. Something to think about though...

I was thinking "screw stabilization, make golf ball chain shot instead."

I know plenty about imperfect trajectories with spherical projectiles, flatline barrels, and the like, I've been around for a little while.
I was more asking about fixes like angling a bit of pipe down near the end. Unfortunately there are a few problems with that; thick steel barrel is gonna be pretty hard to adjust with or without tools, the bore is way too tight to allow any deformations, and the wear problem. Firing numerous golf balls isn't a problem though, I have access to hundreds for free whenever I feel like roaming the fields past the driving range at midnightish times.

I have access to hundreds for free whenever I feel like roaming the fields past the driving range at midnightish times

Oh I hear you there! Driving range isn't too far from me either

I think if you initiate the rotation from the get-go, it might remain on the right path. Maybe you could try putting a .5" or so wide strip of tape inside the breech, perfectly parallel and a few inches long down the top. This might be enough to give the ball some initial top spin. Although, it would probably only last a few shots at best, it might be worth trying, unless duct tape is worth its weight in gold where you come from