Home Forums Reloading Reloading Software Review of New Chronograph

Can the MagnetoSpeed affect barrel harmonics (e.g. the location and size of my shot grouping)?

Anything mounted on the end of the gun can affect the location of your groups because the added mass changes the characteristic vibrations of the barrel. The MagnetoSpeed is intended to be used for velocity measurements only; when shooting for high accuracy simply remove the MagnetoSpeed. Most shooters will use this device to characterize their loads on a short range, before trying any long range shot accuracy trials. Now if you are shooting a shotgun it's another story. Shotgun accuracy and pattern is virtually unaffected and for the first time ever one can chronograph loads WHILE hunting!

I have recently purchased a new chronograph from an outfit called magnetospeed that does not use light sensors. Instead it measures changes in magnetic fields. The sensor attaches to the rifle barrel and looks like a bayonet for the mentally challenged.

I like this chronograph because it is much easier to use than most traditional chronographs and the display/computer module is really well designed. One problem I have encountered is that since the chronograph is attached to the barrel the point of impact and group size are effected dramatically. I deal with this by loading twice the ammo I want to test, firing my standard string without the chronograph to get POI data, then I fire another string with the chronograph attached to get MV. This method is a bit wasteful and it doesn't actually get me the velocity data for the rounds fired.

If anyone at Larue has time for another project I think there would be a market for a mount that attaches these chronographs to side or bottom accessory rails of the OBR and similar rifles.

��Mort