Chronograph

[fho]

How far in front of the muzzle of a black powder gun, do you set your chronograph?

Olie

 

[paulvallandigham]

Try 15 and 20 feet. You need at least the first measurement to avoid a double reading because of muzzle flash, patch and ball. I know a slug gun shooter who has to put his out at 20 feet to get accurate readings.

 

[Greenmtnboy]

Try 15 and 20 feet. You need at least the first measurement to avoid a double reading because of muzzle flash, patch and ball. I know a slug gun shooter who has to put his out at 20 feet to get accurate readings.

yup I diden't put mine out far enough the first time I chronoed my 54 ooops :rotf:
Had to pick everything off the ground but still gave me a reading
:hatsoff:

 

[FTW]

Had mine out abut 10 or 12 ft.Shot it with a patch,penetrated the plastic screen.Still works though.

 

[fho]

Thanks.

Olie

 

[paulvallandigham]

Ollie: You may want to make a physical barrier to protect your plastic screen from impacts, which can still be substantial. My brother and I were talking about this last night. We thought the easiest soluton would be to make some kind of extension that could be clamped or mounted to the topside of the chronograph, behind the laser window, and extend out in front of the screen. Then use a hing to connect a piece of Lexane, the strong synthetic "glass " substitute, so that you can still look through the barrier to get your readings. Pete had a patch or wad actually crack the faceplate of his read out screen and he had to send the machine back to the factory for repairs. We don't want to do that twice!

 

[GreyWhiskers]

Don't know of any down-side to putting the screens 10 yards in front of the muzzle. The bullet/ball will be traveling a bit slower than it is at 6 feet in front of the muzzle. But, average velocity and standard deviation should remain the same.

At any distance you need to make sure that the ball passes through the opening, not the screen itself. :redface: GW

 

[fho]

I am think of setting it out about 20 ft.I talked to a guy that shoots bench slug guns. He said about 9 paces and he is 6ft.2-4 in.tall. I am trying to get a bench slug gun to shoot.

Olie

 

[paulvallandigham]

If he is that tall, his pace should be close to 3 feet, making his distance about 30 feet. My friend, George Mitchell, who built a 69 cal. slug gun, told me he had to set his chronograph at least 20 feet from the muzzle to get decent readings, because of the muzzle blast effect, smoke, etc. Other than the obvious problems of aligning the chronograph with your target backstop, and the muzzle of your barrel, so that ou are shooting over the screens, I don't see any objection to putting it out at 30 feet, instead of 20. The difference in reading from what you might theoretically get at the muzzle would be minimal.

 

[BS]

have found that 20 feet works well for me, about the full length of the cords. When they were set at 12-15 feet, I was getting some 'false" readings. 20' and all works well.