A technical question for an accomplished shotgunner

[Si-Bore]

I was out pigeon shooting today in the seriously windy conditions and was wondering if a pigeon is flying into a very strong wind; at a distance of approx 40m (a longer shot), as well as the normal lead you would apply, is it necessary to allow for the wind too? i.e. more lead increased lead.

I missed a shot that I thought I had allowed enough lead for (yes its a good excuse) but I seriously wondered how much affect the 30-40mph wind would have on the pattern placement? It must have a lot due to the ballistically inefficient shot fired from the cartridge at approx 1300 ft/s(spherical and light)!?

Cheers

Si

__________________

[pin]

An inch perhaps at 40yds, maybe 2". Shouldn't be the reason for the miss. (ps I don't claim to be an accomplished shotgunner btw, just interested in ballistics)

Edited March 1, 2008 by pin

[Si-Bore]

Hey Pin

I would have thought it would have been more than a couple of inches in the 30mph + winds but I could well be wrong as I am guessing? I don't have a ballistic program that could simulate a number 6 shot with an MV of 1300f/s, does anyone else?

 

Cheers

Si

[Big_Sam]

If the pigeon is flying into the wind, its airspeed will be higher than its ground speed.

 

As you cannot see its airspeed, just its ground speed, there is a good chance that you gave it lead for the slower speed, whereas due to the wind it was actually travelling faster in the airspeed. (and miss)

 

What that means is that the effect on the shot will be exactly the same. So give it normal lead --- BUT because it appears to be going slower you will have to allow more lead as if it was travelling faster!

 

 

Confused? True landing a light aircraft in a stiff crosswind. Airspeeds and ground speeds become very important all of a sudden!

[pin]

Um, ********, quite frankly

 

The only speed that is important in this "equation" is the speed of the pigeon relative to the shooter. Assuming the shooter is stationary the speed of the pigeon the shooter will observe is known as ground speed.

 

Quite what the frig the airspeed of the pigeon has to do with the price of fish I can't quite fathom.

 

Airspeed and speed across the ground are really only of interest to pilots and yes you are right it's very important to properly understand them.

[Big_Sam]

Well its assuming that the wind has an effect on the shotgun pellets.

[pin]

Which it will, certainly. I still think your a bit confused with the airspeed / ground speed thing

 

The pellets will be blown by the wind, for sure, but that's still got nothing to do with the airspeed of the pigeon

 

In your example you state a crosswind, a better example is a head or tail wind.

 

If a plane has a stall speed of 100kts and there is as 20kt headwind the plane will need an airspeed indicated of 100kts. This will equate to a ground speed of 80kts - the plane landing in this wind will appear to be going much slower than if there was no wind, but will still not stall and land just fine.

 

If the plane has a tail wind of 20kts (all the rest is the same) then the airspeed will need to be indicating 100kts in order to avoid a stall since the airspeed is the speed at which the pilot tube is passing through the air, the ground speed will be 120kts though as you need 20kts more air passing over the wings to avoid a stall because of the tailwind

[Cranfield]

If a plane has a stall speed of 100kts and there is as 20kt headwind the plane will need an airspeed indicated of 100kts. This will equate to a ground speed of 80kts - the plane landing in this wind will appear to be going much slower than if there was no wind, but will still not stall and land just fine.

 

If the plane has a tail wind of 20kts (all the rest is the same) then the airspeed will need to be indicating 100kts in order to avoid a stall since the airspeed is the speed at which the pilot tube is passing through the air, the ground speed will be 120kts though as you need 20kts more air passing over the wings to avoid a stall because of the tailwind

 

So how much lead should you give this plane ?

[pin]

Lead as in distance in front of it or what size shot?

[Cranfield]

Ah the beauty of the English language...

 

I meant lead, as in how far in front.

 

I never seem to have trouble hitting fast moving birds with the wind in their tail, its the big birds that are moving faster than they look (like geese), that can give me trouble.

[pin]

Indeed, the strength of the wind really shouldn't come into play in compensating for a moving target when shooting with a shotgun - the variance is minimal.

[beretta]

i remember a few years ago shooting a teal (clay that is) in a near hurricane. it was about 30 yards out and i had to go at least 2ft to the left of it to centre it.so yes. wind does affect the shot. and yes i can shoot a bit.

Edited March 1, 2008 by beretta

[pin]

People see lead differently though, I've seen similar when it's blowing on the clays but never found it a problem on the blues. Mind, I miss them wind or not

[markbivvy]

so do i have to learn to fly a plane or not. please.

[casts_by_fly]

let's forget about the bird for a minute.

 

At 40 yd (120') a load of shot traveling at 1200 fps will take 0.1s to get to the target. Using data for #6 shot at 1200 fps and a ballistics calculator, the wind deflection at 40 yd with a 30 mph crosswind is gong to be between 5-7 inches.

 

Now consider that at 40 yd your pattern is in the 3' range. If you had center punched the bird normally you'd have still hit the bird with the outer third of the pattern- result is a dead bird.

 

So while the wind may have contributed, your aim point was still a little off.

 

I was shooting friday too. The birds were coming in at such a range of speeds you really had to pick a lead and hope for the best. Some of the birds were coming dead into the wind and basically hovering because they were so slow. The birds that were coming with the wind were moving well over 60 mph. I didn't shoot at them.

 

thanks

rick

[Scarpa]

The lead may be a touch more - the velocity of the pellets decrease dramatically over a short distance so by the time they reach 40yds they may be doing considerably less then 1200fps.