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Poodleshooter
June 20, 2002, 10:53 AM
Does anyone have experience that they could relate regarding chronographing of shot velocities? I'd like to try chronying some of my favorite loads, but I really don't want to destroy my chronograph. How reliable are the measurements when dealing with an entire shot string? How close do you record? Does the wad interfere with measurements?

stinger
June 20, 2002, 11:10 AM
I'd assume that ALL projectiles would be coming out at the same speed. But what do I know?


Stinger

abrahamsmith
June 20, 2002, 11:57 AM
I've never tried a shotgun, but I've chronographed patched balls in my muzzleloader. Often, the patch would interfere and I'd get really slow results. The best answer I could find was to just get more readings and throw out the ones that were obviously wrong. it would be like 1600 1605 500 1640 600 1620 ...

Also, for the muzzleloader, it helped to put the chrony further away, so that the ball registered long before the patch got to the chrony. This may not be a good idea with a shotgun, though, unless you have really tight chokes! :rolleyes:

C.R.Sam
June 20, 2002, 01:19 PM
Chrono shot at distance.
Put steel plate with hole in it in front of chrono.
Slant plate with top toward shooter.
Put sighting spot on paper over hole.

Shot wads and sabot wads can make your chronograph ill.

Plate also good when doin rifle and piltol down range velocities.

Sam

UK2TX
June 20, 2002, 01:27 PM
Hello Poodleshooter,

In addition to C.R. Sam's suggestions, change the metal vertical legs on your chrony for wooden dowels to prevent shot bounce back.

Regards,

UK2TX

Poodleshooter
June 30, 2002, 06:31 PM
I already shoot with no rods and no reflectors. It works fine on sunny days. I'm really wondering if the wad will interfere with velocity readings, as the patch does on muzzleloader shots. It seems as if you could keep the chrono close and avoid the pattern dispersal problems. Does this give a good reading? I'd love to have the steel plate, but how do you support it? I've got a plate available, but having done stupid things with shotshells in my childhood, I dislike shot "splashback". :o

C.R.Sam
July 1, 2002, 12:21 AM
Support frame for plate can also have table for the chrono goodies. Frame is built so plate hangs from the top from hooks on the back side. Nuther hook at bottom of plate is used to draw plate back at an angle. Plate should shield all the structure so that bounce back is directed into the ground. Make the hole in the plate fairly small so it doesn't have be far away to keep wads and shot cups from going through the hole.

Works out pretty heavy and a pain in the rear to transport and set up but you will get accurate results and no damage to the delicate goodies.....including your personal delicates.

Also useful for getting terminal rifle and handgun velocities. Of course, heavier plate for rifle stuff.

Sam