I took my Shiloh 45-70 out today. I tested a couple of smokeless loads 405 cast at 1450 about 1.9, 350 berry at 1425 for 1.4 but the best was 68 gr of Swiss 1.5 and a 535 postell that shot under 3/4 inch .74. I couldn't get my chrono to read will all the smoke! I will use the Berrys 350 for plinking and the 535 black powder load for hunting and serious shooting.
If anyone has tips on how to chrono BP loads, let me know.

Well I had to put a piece of cardboard over the display to keep it from getting trashed. The bullets went through the screens way before the smoke did.mb

I made a bracket to hold a large baggie in front of the screens. Worked well, caught the lube that messed up the sensors.

I set the chrono up about 20 - 25 feet from the muzzle
Sometimes you need sky screens sometimes not

I went out for a drive/hike in the mountains today. I killed every rock I shot at!