Backspin

[dawump]

Hi All,

I've been reading through old posts. The Z-Body looks like an interesting thing, and it prompted me to make this post. Unfortunately, any mod ( even one that can give good results ) that mean I have to switch to cocker barrels doesn't make any sense. But the concept of the z-body seems logical.

I'd been thinking about trying to find ways to generate friction that would spin the ball in a standard barrel, but thought that "someone would have done it by now" and assumed that it had been tried but just ripped the top of a paintball.. but if the Z-body does it then it must be possible.

Has anyone played around with this idea? Anybody got a Z-body? What is the friction plate like in terms of dimensions and feel? I'm tempted to try to simulate the effect tomorrow and do some testing.

It seems way too simple, but could a 1.5 inch by quarter inch strip of duct tape stuck inside a large bore barrel generate backspin?

Pssst. If this turns out to be true, let's keep it to ourselves ;-)

Keith

[Load SM5]

I tried the Z-body once and it seemed to work pretty well. It just takes small bore paint and a large bore barrel. As far as the duct tape I don't know if that would work or not but your not the first person to try a bit of something stuck to the inside of your barrel. I've read about a guy who stuck a small piece of ultra fine sandpaper to the inside of their barrel near the end to generate backspin. It broke every other ball he shot. And I personally know that you can lick the end of your finger and wipe a little saliva on the inside end of your barrel and occasionally make a flat shot happen but not all the time and only for a few shots. I've never given it too much thought. Maybe a dab of rubber cement? Let us know if you find out anything that works.

[dawump]

I'll play some tomorrow, but I don't have much range here to see the benefit. I imagine if the friction is created at the powerfeed end of the barrel while the ball is slow it shouldn't rip it open. Something at the end of the barrel would be a disaster.

I have some Diablo Blaze ( small ) and a standard automag barrer ( larger ) so you never know.

Keith

[DRAGONSLAYER]

I have heard the rumor about putting RAIN-X in your barrel, they say that with it, you can "shoot through" you ball breaks. I wonder if it would help by making the barrel smoother, causeing more spin?? Just an idea, I've not tried the RAIN-X thing, but it almost sounds like it could help. Anyone else know about this?

[dawump]

I have been experimenting. To summarise, "Wow, WOW, damn, oops, WOW, damn, damn, damn, WOW!!"

In other words the backspin can be created in a standard barrel with the method I suggested, and with enough experimentation and the right barrel this could be an incredible advantage giving a flatline barrels range at the expense of gas efficiency.

For the "friction pad" I chose part of a band-aid, cutting a piece about 3/4" square and sticking it inside the barrel as close to the feed hole allowed by the nubbin.

The first 20 shots I fired at about 40 feet were all DEAD ON accurate, and DID have backspin but it was hard to tell how much, then I had a ball break and discovered the first challenge, that whatever is used to create the friction must create the same friction wet or dry.

I went and sweet-talked the neighbors so I could shoot from one corner of their yard to the far corner of mine, about 80 feet. Results ( I am sure because of the ball break ) were inconsistent, but one in every 5 shots just FLOATED as planned.

My conclusions are that:

1) Barrel match is very important. My barrel ( standard Automag ) with the paint I tried ( medium bore - I ran out of Blaze ) is still too tight, so as recommended with the z-body a loose barrel match is imperative for accuracy, allowing the ball to continue to backspin throughout the barrel

2) I need to find a "friction pad" that behaves consistently over time and after paint breaks. I believe that the paint breaks I got later in testing are due to degradation of the edges of the my pad.

3) This will work best with something like a MAG where the top of the barrel is always in the same place due to the barrel mount.

4) This would be dangerous on the field if not done properly. WITH the friction pad, the balls velocity is reduced so the gun would be adjusted to attain 280 - 300 fps. If that pad comes loose or due to wear or broken paint had a reduced coeficient of friction then the result would be a gun shooting hot. Because of that, even if someone evolved this into a barrel add on "product" it would likely be banned from fields.

5) This has potential, the theory of backspin is not disputed ( although it's overall flexibility is )and the z-body proves that friction can be used to create backspin. All I am doing is creating an un-adjustable insert which does what a z-body does by design. If perfected there are advantages over a z-body ( which due to it's easy adjustment must be chronod with the friction OFF meaning lower fps when tuned in ) but the disadvantage being that it isn't tuneable. The disadvantage compared to the flat line is that any method which uses friction is going to affect gas efficiency.

Perhaps the RAIN-X idea is worth a try, only being applied to the lower half of the barrel, but I don't know. That assumes that the ball is round and touches all points of the barrel equally - which is not true. I still think that generating the spin by having the ball START it's movement with friction at the top of the ball (while velocity is zero) is the way to go to minimise breakage. To really work on a way to do this with a standard barrel I'd like to see a z-body, because they have done the R&D on how to spin a ball.

I'm thinking that instead of the fairly "vicious" use of a pad at the top, a 1/16" x 2" strip of soft rubber ( like an elastic band ) may be better, supplimented by Rain-X on the lower part of the barrel where friction will be increased due to the effective reduction in bore due to the friction strip.

I do believe that actual "contact" needs to be made with the ball by something instead of just a general difference in friction between top and bottom of barrel, because with a good barrel match it is only the paintball seams that touch the barrel - so the actual spin would be determined by the axis of the seam, creating spin relative to that, generating a backspin with an undeterminted lateral element.

I really can't believe that people havn't done this before though! Nobody? It seems so obvious. If a barrel manufacturer came out with a straight barrel that created backspin they would clean up the market. The issues that I am coming up against are that consistency and long life are what is going to be the challenge, which may only be overcome by something in the barrels manufacturing process that creates different friction on the top and bottom of the barrel in the first inch or so of movement.

[ Note. I just wrote a paragraph on how I thought this could be done, but decided that if someone read it and then made a million out of it I would kick myself.. ]

The Automag of course is the ultimate application of this because:

1) It's high pressure, so any causal forces exerted on the ball in the first inch or so will generate a significant effect ( I think )
2) The barrel mount unlike a screw in barrel garauntees that you always know which face is UP.

Keith