Looks to me that the 25 grains is getting close.Pay close attention to the amount of lube that you use on your patches. Dry patches will go low and really greasy patches will go high.

I have a .32 and .36 cal. I use Virgin Olive Oil for a lube.I grease several strips(I cut my patching at the muzzle) and squeeze the excess out and then roll them up in a paper towel.

Looks like you're on the right track.