I have a Shooting Chrony F-1 chronograph. My paperwork says I bought it in 2005. Yes, it was the kind of bargain chrono when I bought it; price was about $90 if I remember correctly. So I've been using this device for 16 years, likely have gotten my money's worth by now.
Over the years, I've had what you might call a few accidents. A couple of times I've shot one of the rods that holds the diffuser panels. Being made in Canada, the metal rods are metric sizes, the rod stock bins at Home Depot don't have the exact size so you have to improvise. The last time around, I decided to experiment with wooden dowel. Same issue, metric vs. inch, but a little sanding took the ends down to size. Or you could grind the holes in the plastic receiver holes they go into, I chose not to do the latter. I guess thinking I might actually get the correct replacement parts some day. More about that below.
My latest caper with the Chrony was I blew the end off of the cable. When you set one of these up, you don't want to set the unit up too high or you imperil it with destruction. There is this thing called parallax, that is, the difference between the centerline of the bore and the centerline of the sighting device. They aren't the same, and you might have a nice sight picture while at the same time the bore is much closer in flight over the chrono sensors. If you have a rifle with a scope with high mounts, you can encounter this issue easily. Or the open sights on an AR, for example.
Anyway, the other day when I set the Chrony up, for some reason for the first time, I looped the little cord end inside one of the dissuser rods, not outside as normal. Just a little quirk. I didn't think it was anywhere near being in danger from a fired shot. It was only about 3/4 of an inch away from the rod and the sensor panel. I had gotten mostly done with my chrono work, when my next shot blew the cord out of the way. Now this would've been a very close thing if a bullet did the damage. But because it was so off center, I'm thinking that muzzle blast ripped it off. After all, those hot gases are blowing right across the sensors behind the bullets. The face of my Chrony has little pitting marks on the label from being peppered by combustion debris.
Having ruined the cord, I decided that now was the time to look into proper repair parts. Nope, they aren't available from Shooting Chrony because the company is out of business. I'll have to make do with the home-made rods, be they metal or wood. By the way, wood works well enough, is cheap to buy, but the diffusers aren't as stable when supported by wood. I've had concussion blow them loose once.
The cord is a pretty easy replacement, as from the factory it was only 6P6C six wire telephone jack cord. You can buy a 25 foot string of it on ebay for about $6.
Before you say it, yes, I know you are supposed to shoot at the target, not the rods. Somehow or another, it happens. Maybe something to do with target replacement. My accidents with the rods aren't unique. Some people manage to fire a bullet into the Chrony base unit itself. Which I have yet to do.
Over the years, I've had what you might call a few accidents. A couple of times I've shot one of the rods that holds the diffuser panels. Being made in Canada, the metal rods are metric sizes, the rod stock bins at Home Depot don't have the exact size so you have to improvise. The last time around, I decided to experiment with wooden dowel. Same issue, metric vs. inch, but a little sanding took the ends down to size. Or you could grind the holes in the plastic receiver holes they go into, I chose not to do the latter. I guess thinking I might actually get the correct replacement parts some day. More about that below.
My latest caper with the Chrony was I blew the end off of the cable. When you set one of these up, you don't want to set the unit up too high or you imperil it with destruction. There is this thing called parallax, that is, the difference between the centerline of the bore and the centerline of the sighting device. They aren't the same, and you might have a nice sight picture while at the same time the bore is much closer in flight over the chrono sensors. If you have a rifle with a scope with high mounts, you can encounter this issue easily. Or the open sights on an AR, for example.
Anyway, the other day when I set the Chrony up, for some reason for the first time, I looped the little cord end inside one of the dissuser rods, not outside as normal. Just a little quirk. I didn't think it was anywhere near being in danger from a fired shot. It was only about 3/4 of an inch away from the rod and the sensor panel. I had gotten mostly done with my chrono work, when my next shot blew the cord out of the way. Now this would've been a very close thing if a bullet did the damage. But because it was so off center, I'm thinking that muzzle blast ripped it off. After all, those hot gases are blowing right across the sensors behind the bullets. The face of my Chrony has little pitting marks on the label from being peppered by combustion debris.
Having ruined the cord, I decided that now was the time to look into proper repair parts. Nope, they aren't available from Shooting Chrony because the company is out of business. I'll have to make do with the home-made rods, be they metal or wood. By the way, wood works well enough, is cheap to buy, but the diffusers aren't as stable when supported by wood. I've had concussion blow them loose once.
The cord is a pretty easy replacement, as from the factory it was only 6P6C six wire telephone jack cord. You can buy a 25 foot string of it on ebay for about $6.
Before you say it, yes, I know you are supposed to shoot at the target, not the rods. Somehow or another, it happens. Maybe something to do with target replacement. My accidents with the rods aren't unique. Some people manage to fire a bullet into the Chrony base unit itself. Which I have yet to do.
? Later.
