Ok, Iíve tried to finish this post 3 times now and each time I do something stupid and lose the entire thing! Grrrrr. So, now Iím writing it in Word and save as I go so I wonít lose all my hard work again.
Thanks to Vince, Iím ready to start loading some test rounds for my 300 win mag. (Vince, I hope you got some rest after arriving home) Iíve spent a fair amount of time looking up loads and all that other fun stuff and now I find myself at an impasse. I might be putting too much thought into this but right now, nearly everything I know about reloading Iíve learned in the last few months so Iím still a little tentative.
Here is the starting load Iíve come up with using the manuals and online data.
IMR 7828 75.0 gr
Remington 150 gr SP bullet
WLR primer - ďuh ohĒ I have CCI 250ís
I found load recipes for 7828 and 150 grain bullets in my Lyman, Hodgdon, and IMR data and they all reference the WLR primer and NOT a magnum primer and thatís where Iím having a problem. Heck, even the guy at Boondocks whoís opinion I respect told me I was supposed to be using a magnum primer and he didnít have an answer when I asked why none of the manuals list data for them. Yes, as Vince told me already, I can load it using a Magnum primer and it will work and many, many people have done it. However, what kind of pressures am I going to be seeing? The Lyman manual uses WLR primers for itís data and merely states that higher pressure will result when using a magnum primer.
Vince, I think you mentioned a recipe you use when you stopped by my store but I was trying to keep track of what was happening there and talk to you and now Iíve forgotten it.
I have found articles that tell me a magnum primer in this case is required for slower burning powders which include 7828 and Iíve also seen recommendations that tell me I should reduce the starting powder charge by 4% - 5% and work up from there. One article even mentioned that pressures can go up by 20% over listed WLR data when using magnum primers!
My gut tells me to start with 75 gr of the 7828 and work up in small increments to 76 or 77 gr while looking for signs of overpressure. I just hope I can spot them since Iíve never seen it before, other than a couple of pictures online. I have some fired rounds and I think Iíll use them as a sort of benchmark to compare to.
Am I over-analyzing?