Dan P.,
I don't know if there are any websites, I never looked. It's quite impressive.
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DP,
The stabiliation from fin stabilization is the same whether introduced by rifling or by feathers.
Not quite. Fin-stabilized projo's need not rotate, depending on the design, the fins can stabilize the flight without any rotation at all. It's imperative to not confuse stable flight with accuracy as associated with guns - a bullet can be perfectly stable in flight yet not be accurate - two completely separate topics.
If you shoot an arrow backwards you do recieve the proper aerodyamics to design nor do the tapered feathers work.
Sorry, I should have been more clear on that one ... "reverse the arrow" should have been the statement - put the fletching in the lead and the tip trailing and I guarantee it'll tumble because an arrow is just like a bottle rocket, remove the stick from the rocket and the engine will tumble and go erratic. Reason being is that the fletching on the arrow, as the stick on the bottle rocket, provide the tail-drag that is necessary to maintain stable flight. Using the fletching to impart rotation on the arrow increases accuracy, a strait-fletched arrow is fully capable of stable flight.
Again, a golf ball is in subsonic flight, any reasonable load under a PRB puts it well into the supersonic range and thus the PRB is a completely different critter.
A roundball with its rather blunt design offers a lot of surface area to length as compared to a bullet.
Theoretically, a sphere cannot tumble and even if it did, it's the same all the way around so it doesn't matter if it does or doesn't. A PRB is NOT a sphere, although it is "somewhat" round, it's not a true sphere. It's not impossible to get very good accuracy from a PRB without rifling-imparted spin such as from a smoothbore but the quality of the balls is directly proportional to the level of accuracy that can be obtained.
Steel shot performed better than expected becasue it was surmised it had a slicker surface and slowed down less for their mass (more like they think the coasrser surface of lead made it slow down more than they thought. Steel shot would likely not take on any consistant spin in a pattern if any spin.
The problem with lead shot is the same as with a PRB, it's easily deformed whereas the ball bearing or steel shot pellets do not deform anywhere near as easily as lead. Drag created by irregular shaped lead pellets will definitely increase drag which is why it is so imperative to provide sufficient cushioning for firing and to keep it from scrubbing against the bore - second part of keeping it off the bore is to keep it from picking up spin. In comparable loads, well protected lead shot will maintain a higher velocity than steel pellets of the same size and at the same range - that's just a matter of momentum by mass. One cannot compare buggered up lead pellets to un-buggered steel pellets, has to be apples to apples or it's pointless. I've seen a lot of those BS stories written by gun rag prostitutes and 99.99% of them are just total BS. Several compared a typical Winchester or Remington factory load with lead shot to a factory loaded steel shot cartridge. The pattern density is BS because 1.25oz of steel contains more pellets than 1.25oz of lead shot of the same size - more pellets in the load, surely it's going to put more holes in the paper .... ooooooh, rocket science
Nonetheless, the lead shot loads used standard $#@* uni-wads, thin petals that don't run the full length of the shot column and a pretty much worthless cushion (except for the Federal wads that look like a coil spring, they actually provided fairly decent cushioning). When you go to the steel shot cartridges, they're running a thick petal full length shot cup and the wad has sufficient strength and mass to stay with the shot longer, by about 5 yards on average and that's long enough to make a considerable difference in the pattern density. When properly loaded with the right components, #2 lead pellets are capable of making a clean kill on a goose at 80 yards - the momentum of standard steel shot loads with BB size pellets is well into the low end of "iffy" at 80yds, one has to go up to T size steel to compare with #2 lead.
A dimpled surface may lessen friction but I bet that they are panels where the air moves by in a crosswise direction such that surface area is actually lessened.
Actually, those I've seen were located on the leading edge and high-drag surfaces. IIRC, it was either Volvo or Mercedes-Benz that began using dimpled panels on cars to reduce drag. The Japanese have been doing it on boats for a long time.