The gun range where I shoot said that I could only use the chronograph in front of the firing line if no one else was there because of safety reasons. I checked on a black powder site. Several people said to go with the magnetoSpeed unit. They average groups about 1 1/4 to 2 inches lower when using it but all said that group size was not affected out to over 400 yards. Also said that trying to shoot through the screens had some effect on there group size at times. Just shoot for zero or check bullet speed, the MagnetoSpeed was easer to use over all. Sold a gen 2 Colt black powder pistol at the gun show Sat. and bought the MagnetoSpeed today. Will try it out soon. 


Steve
Steve