![magnetospeed chronograph magnetospeed chronograph](https://cdn0.thetruthaboutguns.com/wp-content/uploads/2015/03/DSC02436.jpg)
The other reconciling factors from manufacturers stated velocity to chrono velocity could be standardized test procedure. (a) The blast shield should be made of rigid, opaque material of sufficient strength to withstand the shock wave but not be resistant to the passage of the payload.Ĭould this be part of the reason for your spurious readings? Premature triggering of both sensors is typically associated with blast events and will result in velocity readings which correspond to the speed of sound for the conditions present at the test facility (approximately 1,120 fps at sea level and normal atmospheric conditions) for loads below this velocity. Such events can lead to erroneous velocity readings, with the gases or blast reaching the first coil before the payload and prematurely starting the counter-chronometer and causing velocity readings to be low. Large muzzle flash or muzzle blast events may cause false triggering of velocity (light) screens leading as well. Inductance coils can be triggered by ionized gases that may be present at or near the muzzle. It is recommended that a blast shield be positioned between the muzzle of the test barrel and the first inductance coil/velocity screen to minimize possibility of premature triggering of the velocity coils/screens. I'll have one if I need it.Ĭlick to expand.Here is a quote from SAAMI Z299.2ġ1. I have sent an email off to the manufacturer to see if it is salvageable. And after a while the unit stopped working. Setting the bayonet so close to the bottom of the barrel inside diameter, for a shotgun, means, sometimes the wad is likely to be hitting the bayonet. I would get a number I believed, then the next 2 or 3 would be 1400 or 1500 or higher.totally unbelievable numbers like that.ģ. Today I was testing both factory cartridges and some reloads. That is, for every reading I felt like I could believe, I got 2 or more that I was sure were WAY off. Once set, the unit works nicely, EXCEPT you get a LOT of "spurious" readings. Unfortunately, if you have the bayonet that far below the barrel, it doesn't work for shotguns. MagnetoSpeed includes spacers that allow you to adjust the location of the "bayonet" in relationship to the bottom of the inside diameter of the barrel.
![magnetospeed chronograph magnetospeed chronograph](https://john1911.com/wp-content/uploads/2016/07/Dont-like-Magnetospeed-ChronographMagnetoSpeed1.jpg)
In order to get any kind of reading for shotguns, the "bayonet" has to be placed dangerously close to where the projectile is passing.
![magnetospeed chronograph magnetospeed chronograph](https://i.ebayimg.com/images/g/qgMAAOSwsKddL1ZE/s-l300.jpg)
Got up early and was bored this morning so I went to the range to "re-try" using the MagnetoSpeed Chronograph I had inherited from Neil.įirst, let me say that I really like this MagnetoSpeed chronograph.