Fred, due to these higher pressures (this nickle plated brass was fired at least once as "+P"), in your opinion should I then refrain from reloading it for use in my S & W Model 14 K38?
Do you know if "+P" brass is different than regular .38, or considered over stressed for reloading, etc.? I'm not trying to be a jerk, I really don't know the answer and don't want to take the chance of wrecking my K38 (or my hand/fingers)! Thanks.
I would be cautious also, if I had a nice old K38 :-)
There is no difference in the construction/dimensions of the cartridge cases and the case would not be overstressed by the pressure difference (20000psi vs 17000) in the two loadings. I assume that you have once fired brass i.e. that it has not been reloaded by some other reloader who might have used an incorrect load and overstressed the case. Usually the first sign of this kind of situation is an enlarged primer pocket. I have reloaded thousands of 38Spl brass with and without the +P headstamp without any issues.
Since you will be reloading for best accuracy, I suggest that you trim all the cases to the same overall length. This will ensure a nice uniform roll crimp. Can't recommend any loads as I have never reloaded 158gr SWC/RN for target work.