After a lot of looking around for 6.5x52 load info, I finally think I have a starting point. The first thing I did was slug the bore, it comes out to .2682", so I feel safe using the Buffalo Arms .268" 140 grain spitzer bullet. Along with a box of those, I got some Prvi Partizan brass from BA as well.
I found, on the Stevens site, that slower burning powders (IMR 4350, N160, etc.) may cause pressure spikes with the .268" projectiles. That article also advised using magnum primers. I settled on this load from my Sierra Rifle Reloading Manual, 3rd edition.
34.5 grains of IMR 4320 with the 140 grain BA spitzer bullet, with a Remington 9 1-2m primer. COA of 2.900".
Most of my shooting will be at 25-30 degrees Farenheit, so using the magnum primer should not cause problems.
The brass comes sized for .264" bullets, but the tension doesn't feel to be any more than what I get when I size my brass using a whittled down (to .268") 7mm ball sizer. I measured the new brass against my resized (with Herter's dies!) brass, the measurements are identical.
So, I'll load some up and try then out at the first opportunity. Wish me luck!
now dont take my word for it,but i had a guy tell me once that he had an old jap type99 and was scared of full or even medium loads so he used a shotgun powder,i believe he told me he use "universal"....i use universal on all my handgun reloads,but i dont know what it would do in a rifle. im just throwing this out there so maybe someone who knows could tell ya more or maybe you could find it online someplace? sorry i couldnt be more help bro. good luck1....mark