DuckBoat wrote:The mathmatical answer for
40 yd shot = 120 ft
40 mph duck= 58.67 fps
1400 fps shell
Get all numbers in the same units.
Then find how much time it takes for the shot to go 40 yds. 120/1400 =.085714 seconds. Now how far does the duck fly during that time. 58.67*.085714= 5 feet
That is if you hold your gun steady (no swing) five feet ahead of the bird, no wind, and shot maintains 1400 fps at 40 yd.
In the real world shot loses velocity, wind factors, and swing come in to play. This is where someone mentioned above that you use your instincts.
I think your math is pretty good, except the shot will not stay at 1400, it loses speed very quickly. Yours is pretty close to what Brister came up with in his "duck shooting experiment." Bob Brister's book shows the experiment of shooting a moving duck target (12 feet or so of paper pulled behind a car at a constant speed with multiple ducks on it) and holding dead on the lead duck's bill, the shot cloud never got "closer" than 7-8 feet to the leading target, showing the real world lead. This was repeated hundreds of times with the same results, different shooters, hot loads, light loads, etc. Thus, about an 8 foot real world lead. He did the same thing at 60 yards and had to hold in front of the station wagon pulling the trailer to get the shot on the pattern trailer paper.
I used to shoot some tournaments in Texas when I was wild eyed and crazy about competing, and two rebuilt shoulders ago. Got squadded with him twice, and I asked him what he promised his wife to get her to drive a station wagon pulling a trailer that guys were shooting at with live rounds. He just grinned. Dude was a genius writer, one of the best shooters ever, and crazy as HELL. This one guy showed up to shoot in a jersey cow vest, with "cow spots" painted on his gun, cow spotted visor, and Brister says to him "What homosexual dance party did you just walk out of boy?" The dude was MUCH.

So many ducks, so little time....
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