Chronograph question

[Paul_R]

Are standard chronographs, Chrony, CED, Pact, ect, affected adversely using black powder?

Thanks.

[Don McDowell]

No, but if you don't set them back from the muzzle about 20 ft, you might get some strange readings.

[Paul_R]

Thanks Don that was my suspicion. I'm just curious how far it needs to be. I get nervous about shooting the dang thing as it gets further away. But if I did shoot it I'd have no choice but to replace it with a magnetospeed unit.....[smilie=1:

[Gunlaker]

I keep my chrony as far away as the wires allow or I get strange readings. I haven't shot it yet and I've put a lot of bp rounds over it. The main danger is from wads hitting the uprights for the screens I think.

Chris.