I enjoy shooting reduced load cast bullets rounds in my MN1891/30.
I will start, by sharing my jacketed bullet load and then two cast bullet loads and the sighting adjustments.
My jacketed bullet load, which is slightly less than a full power load, but should be good for hunting is:
180grain .311 Remington 180 grain bulk Core-Lokt RN SP (Purchased through Midway on internet)
41.8 grains of Hodgdon 4895
Winchester Large Rifle Primer, Winchester brass
about 3-inch groups at 100 yards 5 shot groups with 1939 Tula MN 1891/30, issue iron sights & my tired old eyes.
OAL about 3.024 inch.
Reduced loads for target shooting.
175 grain cast lead gas checked bullet, sized to .311inch, 33.6 grains of H-4895
155 grain cast lead gas checked bullet,, sized to .311inch, 15.4 grains of Alliant 2400
Both of the above reduced loads are about as accurate at the 180 jacketed load, much easier on the shoulder, but require the rifle iron sights to be adjusted for a theoretically farther distance due to lower velocity.
Once the MN site is zeroed by adjusting the front site to be right on at 100 yards for the jacketed load, the following sight adjustments result in "in the black shots."
175 grain----rear site to 400 meter setting for 100 yd zero
------------rear site to 600 meter setting for 200 yd zero
155 grain----rear site to 600 meter setting for 100 yard zero
I think that cast bullet shooting a milsurp is an interesting chose. While a lot of surpluse corrosive ammo may be as cheap or slightly cheaper that cast bullet reloads, depending on if you cast and if you get free lead, the cast bullets are much easier on the shoulder and allow a lot more range time for practice.
The two Ed Harris reduced loads, The Load with Red Dot and The Universal load with Alliant 2400 are both great starting points for having fun with milsurp rifles. I also like the Hodgdon 4895 - 50%to 60% cast bullet load.