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jnormanh
11-17-2009, 04:05 PM
I ran across a piece of 1/4" plywood I had used to hold a piece of paper for patterning.

It was shot with a 20 ga Remington 7/8 oz #6 shot 1225 fps. 30 yards through an IC choke.

7/8 oz of #6 should be 196 pellets. I count 157 pellet strikes on the plywood, but it's only 24" across the narrow dimension, so 39 pellets could have well missed the plywood.

What is interesting is this - 57 pellets punched clean though all three plys. Of the other 100, some stopped in the first ply, and some in the second and third plys.

Since the plywood must be fairly uniform in hardness, this tells me that some pellets carry considerable more energy than others.

Someone here mentioned Brister's book. I remember that Brister measured the length of shot strings, and at 40 yards found the string to be something like 12' long, meaning a difference if about 10% in shot velocity.

Since energy = m x v(squared), a 10% difference on velocity would = 21% difference in energy. Enough, perhaps, to account for what I observed with penetration of plywood. And a noticeable difference in penetration in game.

What all this means, I dunno'.

jnormanh
11-17-2009, 04:11 PM
backside of plywood

Dakotazeb
11-21-2009, 12:38 PM
A few years ago a friend of mine was saying that he could penetrate a 2x4 at 100 yards with 00 buckshot. Another guy said no way! So the bet was on. We stacked a number of 2x4's together (might have used 2x6's or 2x8's I don't rcall) so there was a large target, stepped back 100 yards and fired a few rounds. Some of the pellets merely lodged in the face of the boards but a few did go all the way through. I was quite impressed. I actually didn't think they would penetrate all the way through, but didnt' bet. :)

JMBZ71
11-21-2009, 01:39 PM
That's an interesting observation jnorm. Those are surprising results (at least to me they are). I'll have to try that with my favorite load -- Federal Premium 12 ga., 1 1/4 oz., 1500 fps #4's.

jnormanh
11-21-2009, 03:19 PM
That's an interesting observation jnorm. Those are surprising results (at least to me they are). I'll have to try that with my favorite load -- Federal Premium 12 ga., 1 1/4 oz., 1500 fps #4's.

Better use something thicker than 1/4" LOL.

jnormanh
11-21-2009, 05:43 PM
A few years ago a friend of mine was saying that he could penetrate a 2x4 at 100 yards with 00 buckshot. Another guy said no way! So the bet was on. We stacked a number of 2x4's together (might have used 2x6's or 2x8's I don't rcall) so there was a large target, stepped back 100 yards and fired a few rounds. Some of the pellets merely lodged in the face of the boards but a few did go all the way through. I was quite impressed. I actually didn't think they would penetrate all the way through, but didnt' bet. :)

If 00 will penetrate 1.5" through wood (the thickness of a 2X), how much damage will it do to flesh and bone? There's a reason cops love, and criminals fear, shotguns.

The little 20 ga load of #2 buck packs the same punch as two .44 magnum rounds. Enough to stop Superman.

Nimrod
12-10-2009, 03:45 PM
I ran across a piece of 1/4" plywood I had used to hold a piece of paper for patterning.

It was shot with a 20 ga Remington 7/8 oz #6 shot 1225 fps. 30 yards through an IC choke.

7/8 oz of #6 should be 196 pellets. I count 157 pellet strikes on the plywood, but it's only 24" across the narrow dimension, so 39 pellets could have well missed the plywood.

What is interesting is this - 57 pellets punched clean though all three plys. Of the other 100, some stopped in the first ply, and some in the second and third plys.

Since the plywood must be fairly uniform in hardness, this tells me that some pellets carry considerable more energy than others.

Someone here mentioned Brister's book. I remember that Brister measured the length of shot strings, and at 40 yards found the string to be something like 12' long, meaning a difference if about 10% in shot velocity.

Since energy = m x v(squared), a 10% difference on velocity would = 21% difference in energy. Enough, perhaps, to account for what I observed with penetration of plywood. And a noticeable difference in penetration in game.

What all this means, I dunno'.


I think you can assume that the pellets that went all the way through the plywood were traveling fastest (they were in the front of the shot string) while the shot found in the 1st ply were at the back.

I've never thought about what could be learned about shotgun patterns by shooting at some sort of ballastic gelatin but theoretically it could be useful information.