Why smaller shot kills
12-23-2004, 10:52 AM
#1
Typical Buck
Thread Starter
Join Date: Feb 2003
Location:
Posts: 973
Why smaller shot kills
So many posts on sites like this show a real misunderstanding of ballistics and how to kill waterfowl cleanly. Much of this is likely lack of experience with effective materials like lead and the prohibitive cost of Matrix, Bismuth and Hevi shot. The following is why we should be trying to find the smallest shot with adequate punch to use at our most frequent range of bird shooting.
The shocking power of a pellet stiking a bird is a measure of the inverse of momentum; what it takes to stop the pellet from advancing. The calculation of momentum is Mass x Velocity Squared. Assume velocity is constant for all loads to follow. If one load, say #4 shot, has a pellet mass of 2, then impact is 2 squared or 4. If two pellets strike the target, impact is 2+2 squared = 16. Two pellets delivered are not twice as effective, but FOUR times as effective. If another load, say a #2 shot, has a pellet mass of 4, then impact from one pellet is 4 squared or 16. So one pellet of the #2 would equal 2 pellets of the #4. If you pattern your gun at your most frequent field range of say 40 yards, and your #4 puts 2 pellets on target and the #2 puts 1 pellet on target, the shock delivered would be the same. However, the probability of a pellet being delivered to a vital spot on target is double for the #4. You are twice as likely to kill the bird cleanly.
If the vitals of a Goose or duck are approximately 1/3 the target area, it would follow that you want to shoot that load which delivers at least 3 pellets to the target area at the range you mostly shoot and with sufficient punch. With lead and expensive substitutes, most 12 guage modified guns in 2 3/4 will get the job done with #6 to 40-50 yds. for ducks and #4 to 40-50 yds. on geese. Beyond those ranges, the Velocity becomes insufficient for the pellet size. To get the pattern at those ranges, it is necessary to move to full choke. To get the punch, it is necessary to go to #4 for the ducks and #2 for the geese, extending the lethal impact to 50-60 yards, though most of us can't repeatedly make the shot meet the bird at those outer ranges.
One reason I refuse to shoot steel and am willing to pay the higher price is that I can not find a shot size which delivers 3 pellets to the target at those ranges after moving up the two pellet sizes necessary to equal the mass of lead or the expensive substitutes in 2 3/4 inch shells. I won't compromise if it means increasing game loss. As the guy who brings the boat and chases the cripples, I can tell you my friends who shoot 2 3/4 steel waste a lot of my time and game. Maybe you can get there in 3 or 3 1/2 inch. Then the other reason would stop me again...the impact of steel on my teeth!
The shocking power of a pellet stiking a bird is a measure of the inverse of momentum; what it takes to stop the pellet from advancing. The calculation of momentum is Mass x Velocity Squared. Assume velocity is constant for all loads to follow. If one load, say #4 shot, has a pellet mass of 2, then impact is 2 squared or 4. If two pellets strike the target, impact is 2+2 squared = 16. Two pellets delivered are not twice as effective, but FOUR times as effective. If another load, say a #2 shot, has a pellet mass of 4, then impact from one pellet is 4 squared or 16. So one pellet of the #2 would equal 2 pellets of the #4. If you pattern your gun at your most frequent field range of say 40 yards, and your #4 puts 2 pellets on target and the #2 puts 1 pellet on target, the shock delivered would be the same. However, the probability of a pellet being delivered to a vital spot on target is double for the #4. You are twice as likely to kill the bird cleanly.
If the vitals of a Goose or duck are approximately 1/3 the target area, it would follow that you want to shoot that load which delivers at least 3 pellets to the target area at the range you mostly shoot and with sufficient punch. With lead and expensive substitutes, most 12 guage modified guns in 2 3/4 will get the job done with #6 to 40-50 yds. for ducks and #4 to 40-50 yds. on geese. Beyond those ranges, the Velocity becomes insufficient for the pellet size. To get the pattern at those ranges, it is necessary to move to full choke. To get the punch, it is necessary to go to #4 for the ducks and #2 for the geese, extending the lethal impact to 50-60 yards, though most of us can't repeatedly make the shot meet the bird at those outer ranges.
One reason I refuse to shoot steel and am willing to pay the higher price is that I can not find a shot size which delivers 3 pellets to the target at those ranges after moving up the two pellet sizes necessary to equal the mass of lead or the expensive substitutes in 2 3/4 inch shells. I won't compromise if it means increasing game loss. As the guy who brings the boat and chases the cripples, I can tell you my friends who shoot 2 3/4 steel waste a lot of my time and game. Maybe you can get there in 3 or 3 1/2 inch. Then the other reason would stop me again...the impact of steel on my teeth!
12-23-2004, 05:11 PM
#5
Join Date: Nov 2004
Location: Northern Arizona
Posts: 507
RE: Why smaller shot kills
You are correct in your calculations but you are assuming that the strike is in a flat plane at points perfectly horizontal to that plane. The ducks I shoot don't cooperate to that degree-they seem to want to fly in patterns other than straight line flat plane. In addition, isn't the underlying assumption also that a strike anyplace on the bird is equally relevant? This too is not the case as striking near the base of the feather or on the chest has a different resistance which offsets the velocity at a different rate. Physics not withstanding-I am the boat retrieve guy as well and there is no doubt that Hevi or almost anything other than steel has a greater ability to penetrate and create a clean kill. It costs more but in the long haul is a much cleaner and effective shot.
12-24-2004, 03:41 AM
#7
Join Date: Sep 2003
Location: Redcliff,AB.,CAN
Posts: 500
RE: Why smaller shot kills
However, larger shot retains more energy over distance than smaller shot and has greater penetration for clean kills. I've been using nothing but 1 1/8 loads for the past 3 years and had very good success leaving the slower, denser patterning 1 1/3.Large, fast shot will win hands down over smaller shot and denser patterns past 35 yd. Inside that range, it really just don't matter, as long as you can hit the bird.
