Paintball Spin Physics - Getting to the final Answer

[Robotech]

You wouldn't need to redo much. I'm thinking perhaps just a modification (and a slight one at that) of the black rotating disk at the top of the pod. You would need to hand load the feed tube (couldn't use the silo) just because you have to get the round oriented correctly. It is the head of the Q-pod where the slight redesign would need to take place.
I mean, just how much longer are the Fn303 rounds than a standard paintball? They don't look THAT much longer.

Also, I would love to find out what improvements were seen during the testing for that round. I understand that one reason they increased the weight to 8 grams was because if it weighed less it did not work as well. However, it would be interesting to know if there was a marked improvement in accuracy and or distance when they used the same shape but on a lighter projectile...say...one that was in the 3 gram range?

[Rokudon]

agreed... Tom, feel like doing some more tests? it would be interesting... and i think hand loading the Qloader would be a porblem because they are spring fed, you'd need something to hold down the pressure.

[Robotech]

I'm sorry that I was unclear. What I meant by hand loading was to put the rounds into the feed tube that go from the Silo to the crank loader for the pods...not hand loading the pods themselves.

Still...all this is moot if a 3 gram round that looks like the FN round is utterly useless because of weight issues.

[hitech]

...all this is moot if a 3 gram round that looks like the FN round is utterly useless because of weight issues.

I do not believe that it would be useless. I'm sure it would be more accurate. How much more accurate is the big question. And I don't think we are going to find out. I'm pretty sure Tom isn't going to do any more testing (it was too costly the first time around). He probably tested some FN303 like rounds that were not weighted, but I wouldn't count on that information being made public either. And before anyone asks, no, I haven't seen it nor do i know if it even exists.

[SlartyBartFast]

He probably tested some FN303 like rounds that were not weighted, but I wouldn't count on that information being made public either.

Manike tested some nylon FN303 rounds.

[hitech]

Manike tested some nylon FN303 rounds.

Well, someone get him to post his results! I'd like to see how much difference they made.

I'm assuing they were not weighted.

[manike]

Manike tested some nylon FN303 rounds.

Yep and they sucked 'behind'.

Not good. At all. Worse than normal balls for accuracy.

[hitech]

Yep and they sucked 'behind'.

Not good. At all. Worse than normal balls for accuracy.

Interesting. I wonder why? Could the gun have been releasing too much air and causing the round to tumble? Very strange. I wonder if Tom had the same problem when first designing the FN303 rounds?

Very odd...

Oh, thanks for letting us know, and so quickly!

[manike]

Interesting. I wonder why? Could the gun have been releasing too much air and causing the round to tumble? Very strange. I wonder if Tom had the same problem when first designing the FN303 rounds?

Very odd...

Oh, thanks for letting us know, and so quickly!

Not weighted. Just solid Nylon all the way through.

They definitely spin... and gave a similar effect to shooting paintballs after you had broken a ball in the barrel. Not good.

[hitech]

Not weighted. Just solid Nylon all the way through.

They definitely spin... and gave a similar effect to shooting paintballs after you had broken a ball in the barrel. Not good.

Did you chrono them? Just curious. It sounds like they were spinning way to fast. At least that is the only thing I can think of. TOM, HELP! You must know...

[manike]

Did you chrono them? Just curious. It sounds like they were spinning way to fast. At least that is the only thing I can think of. TOM, HELP! You must know...

I think I did... 310 FPS IIRC. So a bit fast, but not too much over where we want to be.

Very similar weight to a paintball. But I can check that again.

[hitech]

310 shouldn't be fast enough to be a problem. The only thing I can think of is that they were spinning way to fast. Maybe try some with just a slight twist to the grooves. In your spare time, of course....

[manike]

310 shouldn't be fast enough to be a problem. The only thing I can think of is that they were spinning way to fast. Maybe try some with just a slight twist to the grooves. In your spare time, of course....

I *ahem* borrowed the design from one of Tom's rounds. I figured if he'd already done all the hard work... and they were just for my own personal entertainment, crowd control, lonely winter nights, robber type situations. You know, those times when you just need your own FN303...

[Rokudon]

manike, wat was the twist on the barrel? i'm going by hitech here sayin the spin is too strong. regular rifles need around 1" of twist per 12" of barrel (sniper rounds at least...) but i've seen 1" in 8" i think... or you could try 1" in 85" like the Steyr ACR

[manike]

manike, wat was the twist on the barrel? i'm going by hitech here sayin the spin is too strong. regular rifles need around 1" of twist per 12" of barrel (sniper rounds at least...) but i've seen 1" in 8" i think... or you could try 1" in 85" like the Steyr ACR

There is no twist in the barrel. It was a smooth bore barrel. I shot them out of my FN303.

Some of the fins were slightly 'oversize' and tight in the barrel. They left streak marks down the inside of the barrel... which were perfectly straight (you can still see them in there...) but the rounds in flight would definitely act like they were spinning and fly off in all directions.