Help with case length

[Martini25-308]

Since this 25-308 is a wildcat, there is very little data on this thing so I am taking some precautions and would like some input.

It is back from the gunsmith and I am ready to start reloading. I have just measured the chamber and come up with a consistant number between 2.043-2.042.
I have resized .260 Remington brass with a custom Hornady 25-308 die and they measure 2.035-2.031 in length(untrimmed). What should I look for as a clearence? .010? .015? I have read that most factory ammo will leave as much as .050 clearance for safety.

Rocky,,,, do you have any data on what your chamber measured? Just for a comparison.

I plan to seat the bullet at .020-.025 to start with and tweek it from there.

Thanks for your input, Martini