How many is enough for load

[Bassfish1952]

Note: on load work up for the Pacnor barrel If your geomitry is the same as mine You will reach max velocity / max pressure near 1 grain less than max book load. At least initially stay clear of the max load by a grain or so. work up in small increments.

Barrel mounted Magneto speed will change your barrel tune. Though will offer a lot in terms of reliable velocity data if you are so inclined. Velocity will go a long ways in terms of telling you how you are getting along with pressure. Barrel mounted  magnitospeed should go far in terms being allowed at any range. Primer flatness will offer more clues if you are exceeding pressure.

https://www.youtube.com/watch?v=dVYSG8VO9EU

Thanks
I think I will get a conventional chronograph and make the trip to the farther range. Not sure I am comfortable strapping something on my barrel , plus the indoor range is by the hr. and the outdoor one is same price for all day and allows cleaning between shots . So for workup I will go enjoy myself and do it by the book.
That was a good video  for overpressure . 

Thanks again