you don't test or calibrate a chronograph with a un-known velocity load and ALL loads have un-known velocities. this is because all guns are different. a chronograph is basically a fancy electronic stop watch.... it counts time in fractions of a second. I have used a chronograph in our family business (Aero Space) for about fifty years. first you calibrate them with an oscilloscope. next, I've reloaded for right at 53 years and I really can't imagine what use a chronograph would ever have to the average reloader .... esp. cheap ones that have no accuracy at all.... you may get consistent reading but trust me they are rarely anywhere near accurate. my old chronograph was accurate time wise to 11 places to the right of the decimal point of one second. still a great unit but the vac. tubes became a pain in the back side to replace. can't tell you what we now use as it's classified but I can tell you we don't use an Ohler unit and never have. and ours is a fraction of Ohlers prices. industry uses a screen spacing of ten feet, this alone increases effective accuracy but this is kinda difficult to do with a small prepackaged unit so all the retail makers went to short screen spacing and on top of that overly round off numbers... end result is pure s...
I can get as accurate readings with a pocket calculator and use the known energy/pound of the powder used..... use the Noble Abell equation. can't tell you how many times I've proven that velocity claims by various persons were pure fantasy. even if the person used an expensive chronograph simply because the velocity excided the theoretical max that powder could produce.
but if you happen to be a speed junkie like me..... then you'll need a real chronograph cause none of these cheap units can measure excess of 4,000 fps..... far short of the goal of 5,000 fps we have long worked toward to get true capillary damage and instant death. we first got those speeds with sabots, wonderful little things but built in accuracy problems. forget the sabots and using the powders then known it was impossible til now with the new generation of powders..... no nothing you'll see on the shelves for many years, if ever. funny part is that many of these new super-speed powders are easy to make and safe to make. material costs of under $10./pound. and can make them in your garage.
enough of that side tracked and probably boring you with the true goals that friends like Roy Weatherby had in mind years ago. an idea my dad put in his head.... back when he was doing development work for the army medical corp. 5,000 fps is what roy put in print many times. that's the speed you begin to get capillary shock....... proven by thousands of real live medical experiments done by the army......a BB at 5,000plus fps kills instantly regardless of where it hits...... speed does kill and is now available to us but no one is putting them in a standard rifle. read, learn and enter the new world of hypervelocity.
botton line don't drink the cool-aid put out by chronograph con men, your just giving away your hard earned money
I can get as accurate readings with a pocket calculator and use the known energy/pound of the powder used..... use the Noble Abell equation. can't tell you how many times I've proven that velocity claims by various persons were pure fantasy. even if the person used an expensive chronograph simply because the velocity excided the theoretical max that powder could produce.
but if you happen to be a speed junkie like me..... then you'll need a real chronograph cause none of these cheap units can measure excess of 4,000 fps..... far short of the goal of 5,000 fps we have long worked toward to get true capillary damage and instant death. we first got those speeds with sabots, wonderful little things but built in accuracy problems. forget the sabots and using the powders then known it was impossible til now with the new generation of powders..... no nothing you'll see on the shelves for many years, if ever. funny part is that many of these new super-speed powders are easy to make and safe to make. material costs of under $10./pound. and can make them in your garage.
enough of that side tracked and probably boring you with the true goals that friends like Roy Weatherby had in mind years ago. an idea my dad put in his head.... back when he was doing development work for the army medical corp. 5,000 fps is what roy put in print many times. that's the speed you begin to get capillary shock....... proven by thousands of real live medical experiments done by the army......a BB at 5,000plus fps kills instantly regardless of where it hits...... speed does kill and is now available to us but no one is putting them in a standard rifle. read, learn and enter the new world of hypervelocity.
botton line don't drink the cool-aid put out by chronograph con men, your just giving away your hard earned money