Pellet in flight

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JeroenH
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Location: The Netherlands

Pellet in flight

Post by JeroenH »

Here are some photos of an RWS R10 pellet travelling from my Hammerli AR50 to (and through) the 10.9.
Perhaps find the one in the middle useful in your mental training ... :-)
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Nicole Hamilton
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Post by Nicole Hamilton »

I liked the view from behind, as the pellet exited. It's probably the engineer in me, but I thought that ripple in the paper, like dropping a pebble in a pond, was fascinating! What sort of equipment did you use to capture these shots?
Albert B

pellets in flight

Post by Albert B »

Great photo's Jeroen!
Are you capable of making photo's that show precession and nutation?
As Nicole says, seeing the shockwave traveling through the target is fascinating.
Wat could be of interest: photo's from the side of the target that show how the hole is punched while the paper is stretched and retracts.

Albert B
(The Netherlands)
bigred
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Post by bigred »

Wow. Great photos. How did you manage to time the shots to capture the pellet in that position? What was your shutter speed? Amazing stuff.
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JeroenH
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Post by JeroenH »

Thanks, Nicole and Albert. I found that little shock wave through the target seen from the rear quite fascinating myself.

To satisfy the engineering type of questions...
I did these with the rifle fixed in a clamp, in a totally dark room, with a DSLR camera on a tripod, with the lense wide open for many seconds. Then I fired a flash triggered by the sound of the rifle, with an adjustable delay to capture the pellet on the right moment. I used a normal Nikon flash set on manual, at its shortest flash duration: 1/25000 s, the manual says. With a V0 of 170 m/s, this would give about 7 mm of pellet travel during the flash, which seems about what I saw in the pictures. So it's short enough to freeze most of the pellet's motion, but for .22 or faster, you'd need other flash equipment.
Actually, the delay setting on the flash trigger unit was too coarse. For fine tuning, I varied the distance of the microphone to the rifle. The pellet's speed is roughly half the speed of sound. So moving the microphone 2 cm away from the rifle causes the flash to fire when the pellet is 1 cm further down it's trajectory. Worked exellent, I could capture the pellet just where I wanted.

Albert, I've got your side view suggestion on my ToDo-list.

Some more pictures (and in better resolution) can be found here.
http://album.zoom.nl/user/jhh/Bulb/
RyanIntershoot
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Post by RyanIntershoot »

Fantastic pictures I must say, even if the techy stuff is way over my head!!

Ryan, Intershoot
topshot
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Location: Indiana

Post by topshot »

Bravo from this engineer, too. Nice work. You could sell these.
robf
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Post by robf »

excellent stuff...wanted to do a bit of this myself...but i'd like to get something faster or with less blur...but interesting to see what 1/25000th will get you. :)
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_Axel_
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