BallisticsGuy
Well-Known Member
Yo rose, the question was already solved, by me. He had an instrumentation setup error. After fixing that, everything came together.
Validation question
- Thread starter g0cherr
- Start date
WildRose
Well-Known Member
- Joined
- Feb 3, 2011
- Messages
- 15,226
- Reaction score
- 9,137
- City & State/Province
- N. Texas and S. Africa
Ahh. That's the danger of not reading the entire thread to the end before responding but then it also makes for good discussion when others are looking for a diagnosis.
BallisticsGuy
Well-Known Member
Yup. I do it all the time myself. 
the long and short, chronograph was optical type (put out in front of the gun and shoot in the face type
), it was so close to the muzzle it was picking up combustion gasses and bullets which blew the reading up. Putting it a full 10' from the muzzle fixed him up. There's still 2 clicks of variance up/down but at long range that's easily attributed to a combination of shooter error, group size and round-to-round muzzle velocity variation. It was a hell of an interesting discussion and I'd actually swayed early on to thinking it was click value but that turned out to not be the case which surprised me. As soon as I got data from him on his optic and tests he'd done on it the answer was like a blinking neon sign and a little tweaking of MV inputs put everything in line.
In my side life I run a little ballistics website where I distribute my own ballistics calculator. As part of that I also offer a subscription type service folks can buy. That let's them get access to me to validate & set up inputs for them and to help them understand how to gather the input data in the first place. I always thought ballistics apps were pretty straightforward, at least until I made my own and realized how much room there is for user error to creep in by even very knowledgeable people.
the long and short, chronograph was optical type (put out in front of the gun and shoot in the face type
), it was so close to the muzzle it was picking up combustion gasses and bullets which blew the reading up. Putting it a full 10' from the muzzle fixed him up. There's still 2 clicks of variance up/down but at long range that's easily attributed to a combination of shooter error, group size and round-to-round muzzle velocity variation. It was a hell of an interesting discussion and I'd actually swayed early on to thinking it was click value but that turned out to not be the case which surprised me. As soon as I got data from him on his optic and tests he'd done on it the answer was like a blinking neon sign and a little tweaking of MV inputs put everything in line. In my side life I run a little ballistics website where I distribute my own ballistics calculator. As part of that I also offer a subscription type service folks can buy. That let's them get access to me to validate & set up inputs for them and to help them understand how to gather the input data in the first place. I always thought ballistics apps were pretty straightforward, at least until I made my own and realized how much room there is for user error to creep in by even very knowledgeable people.
