I haven't loaded for ours in quite some time. This said however, it was a bear for me to find a load that shot well out of it. Ouyrs is the older 96 action mil surp so there is a bit of difference in how I went about it.
When I was researching loads the overal majority of folks were shooting the 120gr bulets, where as I was looking for the 140gr range. THe powders which were suggested then and still are now were in the medium to slow burn rate starting witht he 4350's and working up through the slower 4831 and even a few using H-1000. For the most part the most widly used loads were using RL-19 or 22 with the 140's. Most used a gentle primer like the CCI or Rem, where I was using the Win WLR. This might have been most of or at least part of my problem as once I switched to the CCI-BR2 I got very acceptable accuracy. Our 140gr load used H-4831 and the Hornady A-Max. The top end velocity was only in the mid 2500fps range though so the over expansion or bullet blow ups were a non issue. THis particular bullet was THE only one out of every other I tried that would group well in this rifle. When I say well I mean around an inch at 100. I have to believe that this is simply due to the extra long throat it has, as I can set the long AMax on the top of a case and chamber it without it ever touch the lands. Witht he AMax moving along at such a slow initial speed it still carried well out past 300yds and I cleanly took plenty of hogs at ranges from 10 through 400yds with them before evern allowing my daughter to use them on a deer. The several nice bucks she did use them on all dropped in their tracks, and for anyone who didn't know better the holes in each side wee nothing more than what you would have found using any other cup and core bullet, caliber sized going in and quarter or half dollar sized comeing out. Nothing in between was ruined or bloodshot either.
We shifted to some of the Privi Partsan 140gr loads a couple of years back simply to use on the hogs. We found it shoots 1/2MOA at 100yds with three different shooters rangeing from 8yrs old through 45yrs old doing the shooting into one group. Not bad at all for 12 rounds. We were so impressed I ordered up a dozen boxes and have happily been using it to hunt deer and hogs since.
Your rifle will alloy you to get up and into some decent velocity and utilize a few other new powders they have on the market. Personally I would look hard at the Hornady 139gr offerings and not look back. With Hornady you at least get 100 per box for less than what some of the "premium" bullets cost for 50. I have used both the SP and the SPBT equally in several rifles and find they do a fine job of accuracy and game dropping both on the deer and hogs.
Hope this helps.
Mike / TX