And everyone please note ** max charge pressure reached with 124 gr JHP using only 4.1 gr of WST due to shorter OAL of 1.090" although velocity listed shows 1040 fps.
At that loading, if using mixed range brass with work hardened brass that will "brass spring back" to produce less neck tension and increased bullet setback, resulting chamber pressures can go higher. So definitely check bullet setback after feeding/chambering dummy rounds (no powder, no primer) from the magazine when working with higher WST charges and use thicker case wall brass that won't produce bullet setback -
https://www.thehighroad.org/index.p...neck-tension-and-bullet-setback.830072/page-4
Glad to see nice compilation of data coming together.
So looks like when using 124 gr FMJ/RN at 1.135" to 1.150" OAL, 4.0 gr would be good start charge and 4.6 gr would be non-compressed max charge provided that you are not experiencing any bullet setback (perhaps with use of thicker case wall brass) but for 124 gr JHP, use greater caution due to shorter OAL/bullet seating depth produced and consider reducing start charge down to around 3.6 gr and using 4.0 gr as non-compressed max charge (I can do case powder fill calculations later).
While I have worked with slightly compressed powder charge loads in the past, since most THR members use mixed range brass with unknown reload history and condition of brass that often results in bullet setback, I won't speculate on higher than 4.6 gr compressed WST powder charges. If you want to venture beyond 4.6 gr, be sure to use thicker case wall brass that do not produce any bullet setback.