300 WSM with 195 TMK

[BjornF16]

Novice reloader here...I’ve reloaded 308Win and 6.5 grendel previously.

I’m running short action Stiller with Accurate Mag DBM and Proof barrel. With the 195 TMK, my maximum COAL with reliable feeding gives me a .095” jump (measured with Hornady OAL gauge).

Using H4831SC, 63.5 grains gave me 2730 FPS with ES=4 (3 shots) during initial work up (63.5 - 66 grains). ES steadily increased with increasing charge weights.

Accuracy was just over 1 MOA with 63.5 and 64 grains.

Question: Is .095 to .135” jump excessive if I play with seating depth to find better accuracy?

 

[83cj-7]

That kind of jump is fine. There is an article on the Precision Rifle Blog about bullet jump and accuracy/consistency. I really agree with the findings. I have several rifles that shoot amazing with bullet jump from .110 to .130.

 

[BjornF16]

I read those articles...thanks for the pointer.

Some of that jump appears to be from increasing free bore (if I understood the article).

I was also concerned about seating to deeply into case as I’m currently deeper than the neck/shoulder junction.

I will load some rounds going progressively .005” deeper and look for accuracy improvement.