RescueRandyMD

That looks like an awesome method, thank you! Also I love the excel sheet too... I am logging my loads into something similar and it will hopefully be very useful in years to come

True, the factors at play I feel I would be chasing my tail chasing one parameter and then neglecting another. I feel like most others stated just finding a OAL that works would be best, then work up powder/velocity. It would be a whole other story for 1 competition gun with a OAL/velocity workup because, like snowflakes, every gun is special And yes I only have the plated for plinking I have 115gr HAPs and 124gr JHP MG that I will be doing the workup for to see which ones those guns like each

Thanks. I'll just workup from 1.13" and it would definitely make things easier

Gotcha. They all will cycle 1.1" or 1.16" so is there any dogma about increasing accuracy or short jump to the rifling that applies to pistol OAL?

Hi All, Currently have been doing a ton of load workup for a couple 9mm handguns (P226 and VP9) and trying to go more scientific. Been using 115gr CPRN with 4.2gr of Titegorup at 1.15" since it worked well and didn't question more parameters till now.. I have poked around this forum a bunch and read a lot about load workups... but one thing that has eluded every topic seems to be adjusting powder charge for varying OALs. It makes sense doing a ladder workup for a powder. 115gr CPRN 9mm bullets with 4-4.5gr of TG at 1.10" OAL... and see which shoots best. While I found 4.2gr to be very accurate, I wanted your guy's opinion on changing to a longer OAL to see those affects on accuracy. I've read the longer OALs closer to rifling should improve accuracy if the jump to it in 5-20 thousandths... but I've also read that shorter OALs seem to be more accurate for 9mm. While I want to do a OAL work-up from 1.10-1.16" (Max OAL for both guns are 1.24" and 1.2"), I can't help but wonder how much the velocity will drop too with a longer OAL, more case space, and less pressure. Maybe my sweet spot OAL is at 1.3", but with a different pressure and velocity I now have more than 1 variable at play affecting accuracy and it ruins the scientific work-up. As an example, the Lyman manual lists a 115 gr JHP @ 1.10" OAL and 4.5gr Titegroup making 31,400 CUP. Running some math on changes in case volume for longer OAL seating at 1.16", the pressure would be 27,100 CUP (or about the same pressure as if the 1.10" OAL load had just 4.0gr of Titegroup). While there are other factors at play for velocity and other variables had to be assumed... it shows that 9mm is sensitive to OAL variations. So... my question is the following: For increasing the OAL for a load work-up should I A ) Not worry about changing the best powder charge, find the best OAL working up from the min, then readjust the powder charge at the new found OAL. B ) Chrono the longer OAL and adjust the powder charge to achieve the same velocities so the only independent variable is the OAL