Thanks Alpha!!
So that would be roughly .55 feet per second with the BB shot and .29 feet per second without.
The reason I was asking is for a comparison to the typical winter spider rigging speed we use on Sardis, which is .3 mph. It's amazing that going .4 or .5, just a couple of tenths faster will generally kill your bite, but it's true in the cold water, we use chains, drift socks, whatever it takes to slow down.
At any rate, I had the idea of comparing that speed to the TM fall rate.
.3 mph would equate to a .44 fps fall rate, which is right in between the two trout magnet fall rates, weighted or unweighted
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Now I need to figure out the math to replicate .3 mph on the reel-in speed:
On a 40' cast, you would have to take 90 seconds reeling it in to achieve a .3 mph retrieve!!