210M worked the best in my gun also.
Improving ES in 300 WM is it just powder selection
- Thread starter hudel
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BMF
Well-Known Member
I also find that interesting....
So did your velocity go up with H1000 or H4831.... or both?
The magnum primers were not around when the 300WM was developed, the standards primers is what that round was designed for in the beginning. The powders have come along way also since the 60's.
For what it's worth, my gun really likes IMR 4350 as far as accuracy is concerned, but I prefer the H1000 for the temperature stability.
I don't find that amazing at all. Velocity is a function of the pressure curve (among other things). A magnum primer creates a hotter initial burn but in a large case, the pressure could drop off at the final burn. Ideally, the pressure rises evenly and smoothly throughout the burn giving rise to maximum velocity as the bullet exits the bore. If you just try to imagine a pressure spike earlier in the burn when the bullet isn't even going that fast yet and a subsequent lower pressure at exit, you can easily see why a magnum primer might not produce as high a velocity as the standard primer in all cases. It's somewhat the same as the way that faster powders don't necessarily produce the highest velocity. Try plugging your data into an internal ballistics program like quickload, but make sure you read the documentation to learn how to play with primer types. It's a fun and very informative way to play with loads.
jrg
Well-Known Member
Try CCI-250's as well, I shoot rl26 in my 300 wm with 215gr hybrids and I got significantly better SD/ES with CCI vs the Federal 215m.
I had the same discovery with my 7 SAUM and using Federal 210m primers over a magnum primer, both with H1000 and RL26.
*I have several shooting buddies who have had the exact same discovery. Most of us don't use the 215m primer unless it's in the really big magnum's - Ultra mags, Normas and Lapua.
I had the same discovery with my 7 SAUM and using Federal 210m primers over a magnum primer, both with H1000 and RL26.
*I have several shooting buddies who have had the exact same discovery. Most of us don't use the 215m primer unless it's in the really big magnum's - Ultra mags, Normas and Lapua.
I lubed neck lightly for mandrel sizing withlee case lube. When trimming i use a qtip with alcohol on each neck to remove lube etc
Your the second to suggest non magnum primers, Im gonna try it for sure, im down to the last few magnum primers anyways
TBH i just seated same depth as similar factory ammo for testing purposes, was tryingto tune ES and SD before adjusting seating
As far as neck tension im using a PMA tool expander mandrel as a seperate step, i would think it would be pretty uniform?
Where did you find the ONLINE TARGET?
ShtrRdy
Well-Known Member
Do you do any case cleaning before resizing and then expanding?
Getting the inside of the neck extra clean could be causing some problems. Try an experiment where you don't wipe out the inside of the neck . Just leave the lube you used for neck expanding in there. I like to use Redding Dry Neck Lube for the inside of the neck before running the neck over the expander mandrel.
You might see some improvements in your ES and SD with different seating depths. Not sure where you are at now, but play around with jumping in increments of .015" or .020" with 5 rounds per depth and you might find a place where your pressures/velocity are more consistent.
