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Discussion Starter #1
I've been playing around with a spreadsheet that compares leads/shot velocity/drops etc.

The one piece I can't find is how much and how fast the clay slows down once it leaves the trap.

Does anyone have actual data or educated guess on the speed vs distance of a clay target from a trap machine?

I know the starting velocity is around 40-42MPH.

Thanks,
AJ
 

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I've been playing around with a spreadsheet that compares leads/shot velocity/drops etc.
Just point the gun ahead of the target. A little bit on most angles and just a little bit more on hard angles. The farther you move back, the little bits increase a little bit more. The leads do not materially change regardless of the initial velocity of the ammo. If you shoot so slow that you have pattern drop, don't worry, the target is dropping way faster than the pattern by then. Take your spread sheet and make a 2 inch circle in the middle. Hang it up at 13 yards and shoot at the circle. Now you know what your POI is and you won't have wasted a piece of paper.
 

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At least it was a trap target question. If Neil comes along, he will have your answer.
 

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When we use a radar gun to set targets, speed is set @ 44-45 MPH inside the house.
When we are at the back of the house holding the radar gun just high enough to clear the house speed is set @ 42-43 MPH

From the time the target leaves the arm it is loosing speed.

I think you can look at the decrease in speed as a linear function and be close enough for what you are approximating.
Assume a target is thrown 50 yard, At 25 yards from the trap house the target is traveling approximately 22mph.

Its All Good

West
 

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Discussion Starter #8
Thanks guys for all the great info.

I'm a math guy by trade and numbers are interesting to me.

I understand it's probably in the minutiae, but it's single digits and wind outside.

I've decided that Time of flight differences (for the shotstring) from 1145-1300fps (even for #8's vs 7.5's) is so close that it really shouldn't matter from 16-27yds.

I'm sure you all knew this innately, but I like to understand things from an intellectual perspective.

Sorry to waste your time, you can now proceed back to the discussion of lack of shells in California or the Tristar phenomenon ;-)

Mods can delete the thread and ban me for posting drivel now.

AJ
 

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Don't think of lead as a measurement, think of it as a feeling look hard at the target and your brain will know when to pull the trigger. If you try to calculate and measure you will more than likely stop the gun when you see what you think is right. I only know because I've done it time and time again.

Shoot well! Mike
 

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Discussion Starter #12
Don't think of lead as a measurement, think of it as a feeling look hard at the target and your brain will know when to pull the trigger. If you try to calculate and measure you will more than likely stop the gun when you see what you think is right. I only know because I've done it time and time again.

Shoot well! Mike
I appreciate that, my thoughts where more around how a change in velocity would impact the actual center of the pattern at the target when you shot 16 and handicap.
From a math perspective, I've decided that the time of flight difference is so small that finding a shell (reload) that patterns well and sticking to it is all that is needed.

Then as a friend of mine told me last month "Buy a ton of shot, reload and shoot it all, You'll have then seen enough targets to have a foundation to work from!"

Thanks again,
AJ
 

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AJ, a late contributor to this site, my friend Pat Ireland, and I both had top-quality radar guns which tracked targets from the 27 until the the shooter smoked them and then the guns stopped counting and left their last recorded speed in the readout. We agreed that a straightaway clocked that way generally disappeared from the air (and the radar gun) when it was being tracked at about 33 MPH.

Let's do this in our heads. Since 60 MPH is 88 feet-per-second, we will call one MPH 1.5 feet per second. That means the 33 mph we saw was about 50 feet-per second.

The line of the shot at the hardest right or left bird intersects it at about 28 degrees; we can use trig to see that its horizontal speed relative to the line of our shot is the speed of the shot times the sine of 28 degrees. We know the sine of 30 degrees is 0.5 so we will use that.

All we need do is multiply 50 feet-per-second by 0.5 and we have an approximate "crossing" speed of the hardest target we shoot as about 25 feet-per-second.

You can use that speed for any kind of lead-calculations you want and know you explored the "worst case;" any lead you need will be less than that.

Yours in Sport,

Neil

By the way, what that means in terms of required lead at singles is, for all but the hardest angles, pretty much within your pattern if you center it.

Imagine you have a trap to yourself standing on post 1 and have locked the trap at a little more centralized than a straightaway. You start by shooting right directly at the target and since it is almost a straightaway, you smoke it.

Move to post 2 and still shoot right at the target, trying for no "lead" at all. What happens? You still hit it pretty hard.

Move to three, keep shooting right at the target and the breaks are barely OK.

On 4 the breaks are chippy for sure, but the target generally still breaks.

On five there are a lot of misses. By now your you really do need some lead.

Now think about that fellow shooter on your squad last summer who was missing a lot of targets. He told you "I know what I am doing wrong. I'm reading that slight angle as a straight-away and shooting right beside it."

Is that what he's doing wrong? How do you know?
 

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Discussion Starter #15
AJ, a late contributor to this site, my friend Pat Ireland, and I both had top-quality radar guns which tracked targets from the 27 until the the shooter smoked them and then the guns stopped counting and left their last recorded speed in the readout. We agreed that a straightaway clocked that way generally disappeared from the air (and the radar gun) when it was being tracked at about 33 MPH.

Let's do this in our heads. Since 60 MPH is 88 feet-per-second, we will call one MPH 1.5 feet per second. That means the 33 mph we saw was about 50 feet-per second.

The line of the shot at the hardest right or left bird intersects it at about 28 degrees; we can use trig to see that its horizontal speed relative to the line of our shot is the speed of the shot times the sine of 28 degrees. We know the sine of 30 degrees is 0.5 so we will use that.

All we need do is multiply 50 feet-per-second by 0.5 and we have an approximate speed of the hardest target we shoot as about 25 feet-per-second.

You can use that speed for any kind of lead-calculations you want and know you explored the "worst case;" any lead you need will be less than that.

Yours in Sport,

Neil

By the way, what that means in terms of required lead at singles is, for all but the hardest angles, pretty much within your pattern if you center it.

Imagine you have a trap to yourself standing on post 1 and have locked the trap at a little more centralized than a straightaway. You start by shooting right directly at the target and since it is almost a straightaway, you smoke it.

Move to post 2 and still shoot right at the target, trying for no "lead" at all. What happens? You still hit it pretty hard.

Move to three, keep shooting right at the target and the breaks are barely OK.

On 4 the breaks are chippy for sure, but the target generally still breaks.

On five there are a lot of misses. By now your you really do need some lead.

Now think about that fellow shooter on your squad last summer who was missing a lot of targets. He told you "I know what I am doing wrong. I'm reading that slight angle as a straight-away and shooting right beside it."

Is that what he's doing wrong? How do you know?

Thanks, and some additional rough math shows that the time of flight difference between #8's at 1145fps and #7 1/2's at 1300 fps is around .01 second out to target breaking distances. So 25feet * .01 = about 1/4 foot or 3". So fast loads and slow loads essentially require the same lead.

Thanks,
AJ
 

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AJ, what you and most who consider this conundrum fail to realize that the issue is not target velocity change or intersect angles, but target rise. It's going up, damned fast, and peaks at about 30yds, then begins to fall. If you don't get it on the way up, you're most likely not going to hit it with any consistency, at least. So speed of ejecta does, in fact, matter. Also, before you tack your chart up and shoot at it, consider what your shot string is doing after you've determined, from 20yds, or whatever, that your gun is shooting 90/10 above aim point. Isn't it interesting that the shot string is rising at about the same rate as the target you plan to break? It's why our Pennsylvania farmers who master 16yd targets with their flat shooting field guns, won't shoot handicap.
 

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AJ, what you and most who consider this conundrum fail to realize that the issue is not target velocity change or intersect angles, but target rise. It's going up, damned fast, and peaks at about 30yds, then begins to fall. If you don't get it on the way up, you're most likely not going to hit it with any consistency, at least. So speed of ejecta does, in fact, matter. Also, before you tack your chart up and shoot at it, consider what your shot string is doing after you've determined, from 20yds, or whatever, that your gun is shooting 90/10 above aim point. Isn't it interesting that the shot string is rising at about the same rate as the target you plan to break? It's why our Pennsylvania farmers who master 16yd targets with their flat shooting field guns, won't shoot handicap.
I have tested my shotgun, it is 3" high at 13 yds.

--begin rough off the top of my head calculations.
Interesting thoughts on the rise rate. If the target rises from zero to 20' high in the 1 second between pull and break, that means it is rising at only about 13mph, even though it seems faster. But since we don't get the advantage of the angle (Sine of an angle to reduce apparent lead), It can rise 2+' between shot and break!
--end rough off the top of my head calculations (let me know if I fubar'd it)

I'll get all this stuff stored in the brain before the spring thaw and hopefully be able to put it to good use.

Thanks again all,
AJ

Most ATA set targets get to about 17 feet.
So it will rise more like 1'-1.5 feet between bang and break ? (depending on how fast a shooter is).

Thanks,
AJ
 

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AJ you have to shoot targets to find your poi,its the sweet spot where you can turn a target into a ball of black smoke the size of a trash can. When you find your pio you will know!!! Henry Winn
 
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