I recently purchased a Magnetospeed V1 ballistic chronograph to get yet more data in my search to perfect load development. I have used it on centerfire and muzzleloaders with good success. I have replaced a couple sky screens on my Oehler 35P and taking a chrono coffin downrange takes to long and is a pain to set up on a public shooting range.
The unit mounts on the barrel so it reads the speed as the bullet exits the muzzle. Since the bullet is decelerating from the moment it leaves the bore, the speeds are higher then the units that are mounted 10-20 feet downrange. It does eliminate the need to correct the chronograph reading to get true muzzle velocity.
I have not had any problems getting readings of saboted bullets or bore diameter bullets. Since the unit does contact the barrel, I have seen a point of impact shift when using this device. I still get good groups but the placement moves. So far the movement has been less than 2 MOA. I zero the POI then use the chronograph to get the speed data.
Magnetospeed now has a V2 on the market. They have modified the attachment method and have added a hard case. They have also given more flexibility on barrel sizes. They do offer upgrade kits to those that have the V1 version.
The unit mounts on the barrel so it reads the speed as the bullet exits the muzzle. Since the bullet is decelerating from the moment it leaves the bore, the speeds are higher then the units that are mounted 10-20 feet downrange. It does eliminate the need to correct the chronograph reading to get true muzzle velocity.
I have not had any problems getting readings of saboted bullets or bore diameter bullets. Since the unit does contact the barrel, I have seen a point of impact shift when using this device. I still get good groups but the placement moves. So far the movement has been less than 2 MOA. I zero the POI then use the chronograph to get the speed data.
Magnetospeed now has a V2 on the market. They have modified the attachment method and have added a hard case. They have also given more flexibility on barrel sizes. They do offer upgrade kits to those that have the V1 version.
