Quote:
Originally Posted by Dragon88
Decreasing velocity with increasing charge is a phenomenon that has been noted before, and I've seen it myself two or three times. Honestly though, the velocity differences you experienced are very small and don't mean much. These could easily be explained by temperature of the gun, temperature of the ammo, powder position, bad chrony reading, etc. Velocity results aren't always perfectly linear across loads, guns and barrel length.
As for the difference in POI, this is also easily explained. Different gun, different sights, different sight picture, etc.
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However in this case we are talking about _
decreasing charge_ with _
increasing velocity_ **opposite of normal behavior** (or is that what you actually meant?)
I don't consider 200 fps more as a small difference, that doesn't mean much... especially at +P pressures.
temps were normal for this area, all shots were positioned the same and chrony readings were consistent for the session.
Undeniably they are different guns but tell me how much difference is there really between two J frames with the same bbl length) when you align the top of the front sight with the top of the rear notch holding on the bottom of an orange dot 10yds away ? I suppose the main difference is that one is matte silver and the other is satin black? I guess they are just different guns and I will have to adjust to it for now but I would expect them to be factory calibrated by design to shoot to the same POI with the same ammo if it is going the same speed - which I see the one clocks a little slower then the other-
so there must lie the answer! it must be the tolerances in chambers and cyl gap showing up.