Frylock wrote:The problem is with calling non linear burnishing marks on a choke tube 'proof' or 'fact' of shot cup spin, as has been pointed out other factors could be at play to explain the burnish marks. To be any sort of proof first all other possible causes would need to be eliminated. Until then everything is just speculation.
clampdaddy wrote:I have one choke tube (kicks hff) that seems to be imparting a spin on wads. With the factory chokes the wads all head towards the pattern board but when I have that KHFF tube in, the wads immediately exit stage left at about a 45 degree angle and spinning like a ceiling fan on high. Patterns are great though. Weird. Maybe the spinning doesn't actually start until after the shot has cleared the wad?
Here's a can of worms from a chat with my Engineer pal at Bombardier Aerospace.
Look into whether or not there are any significant rotational forces created by conservation of motion upon setback. If it so happened that enough pellets smashed into each other the right way, being all forcing it clockwise or all counterclockwise and what about those that half go CW and the other go CCW?, it could be that some force is translated into the radial axis. Along these lines, I wouldn't out rule the possibility.
FYI we came up with a ton of reasons why this wouldn't work. Though there is no reason why it couldn't work under the right circumstances... in fact a load could even be designed to create such a rotation in a smooth bore. That's an interesting hypothesis however it would certainly have to be counter to conventional loading practice and perhaps not using round shot or inconsistent shot mass on different quadrants by using a spreader X or some other means, this is certainly not the case in this instance though I don't think however with some people who knows how or what they load.
I don't believe it's about who wins here... it's about the what if he's right? What if that changes your ideas of what loads will pattern better? Even though he says it's nothing to worry about, if that thing is spinning anywhere near the "rpm" he said it was we'd all have a problem hitting ducks... what if we do have a problem hitting ducks!!??!
An open mind and correctly applied engineering principles is a great thing however doing conventional things in unconventional ways sometimes leads to even greater things.
Mugzwump wrote:also.. you guys need to stop writing the word "ejecta"... every time I read it I first think about some sticky magazine pages... that sh!t don't spin.
Jon Bergren wrote:Frylock wrote:The problem is with calling non linear burnishing marks on a choke tube 'proof' or 'fact' of shot cup spin, as has been pointed out other factors could be at play to explain the burnish marks. To be any sort of proof first all other possible causes would need to be eliminated. Until then everything is just speculation.
Then please explain how the burnish marks got there. You can't nor can anyone else. Ned S
slowshooter wrote:Mugzwump wrote:also.. you guys need to stop writing the word "ejecta"... every time I read it I first think about some sticky magazine pages... that sh!t don't spin.
Jimmy82 wrote:Hey Ned,
I'm having trouble with the math. I'm not trying to dispute anything, I'm just curious by nature and I like math. However, I haven't touched a physics book in over a decade. Check me on this, according to the numbers a 1700 fps load with a 1/32 of an inch of spin in a 2-3/4 inch distance came out to 11.25 degrees of spin at 20400 inches per second. 2.215 inch circumference, and 1/32=.0692, so (.0692*360)/2.215=11.25 degrees. Which means it travels forward 2-3/4 inches in .000135 seconds, and spins 11.25 degrees in that same time. 360/11.25=32, 32*.000135=.00432. A full revolution takes .00432 seconds, 60/.00432=13888. So according to that math, the rpm should be around 13888.
This is assuming speed during the last 2-3/4 inch is constant, which I know it's not, but I figure the acceleration would be close to negligible in .000135 seconds. Also, extremely long decimals have been rounded.
Yuchi1 wrote:HWl barrels were specifically marketed as having the capacity to arrest "spin" of the shotcup/payload as it traversed down the bore. Can anyone present conclusive evidence (of, proof quality) this constituted false advertising?
mudpack wrote:Hastings invented a barrel that will stop wad spin.
I've invented a small black box that produces a force field that will keep the planet Kolar from falling on your house....$19.95 plus shipping and handling.
There must be a need for both products because someone makes them....and no one would make a product if there wasn't a need for it, now would they?
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