I just started reloading and started with my 270 Winchester which I had good success with. See the thread below in the sub-forum.
I am shooting a Marlin 30AS and a Husqvarna 648 built on a FN98 receiver. Money is not an issue, so I could buy separate powders for each. I was just looking for something economical and convenient. I also plan to get a 308 Winchester, again, and IMR4064/3031 would fit it as well.
I'm trying to assign a role for each rifle. 30-30 170gr for blacktail/blackbear <150meter iron sight hunts in dense forest, 270 winchester for 300m+ whitetail/mulie hunts in foothills/alpine situations, and an all rounder 8x57 200gr fully loaded to WWII Wehrmacht power level that can take down bears, moose, elk etc at distance or in close, and function as a wilderness utility rifle.
I'm still learning about ballistics on game animals, but isn't the purpose of shooting heavy for caliber bullets to maximize penetration via sectional density? The high efficient cartridges between .264-.284 (6.5x55, .270Win, 7x57, .280 Remington) caliber are considered ideal because they have high BC, with the bullets being long and sleek providing for improved trajectory and penetration by design? However, if you shoot the heavier weight bullets in these calibers, you can further increase penetration via sectional density? We focus a lot on velocity and bullet mass and the kinetic energy = 1/2mv^2 formula, which favours increased velocity given the squared value. However, a lighter bullet having a flatter trajectory and higher velocity, may not penetrate adequately into medium-heavy game, hence the bullet design also factors in, which confounds terminal ballistics.
I pulled these descriptions from Hornady's website, and based on this, one might choose one of the medium weight bullets for caliber (i.e. 165gr in 30cal, or 140gr in .270cal), with an expensive bullet (Nosler Ballistic Tip or Partition) that expands for the game targeted, and lands in the middle of the caliber's velocity range allowing for a cartridge that optimizes all 3 factors as much as possible. Lastly, for long range shooting, don't heavier bullets tend to be more accurate as they are more stable in the wind?
DESIGN
Bullets designed with heavier jackets tend to stay together better and penetrate deeper, while lighter jacketed bullets tend to fragment and expand more rapidly, creating a wider wound channel and increasing temporary cavitation, but generally don’t achieve as much penetration.
Expansion can be controlled by the bullet’s tip design and by the jacket construction. Rapidly expanding bullets create a wider wound channel, displacing even more tissue and increasing temporary cavitation, but they also increase drag, thus requiring more energy and momentum to drive through tissue, and in general don’t penetrate as deeply as bullets designed to expand more slowly. Expansion is beneficial, but penetration is essential in order to ensure that the bullet reaches the animal’s vitals.
SECTIONAL DENSITY
A bullet’s sectional density also affects the amount of damage it can cause. Sectional density (a bullet’s weight in pounds divided by its diameter squared) describes a bullet’s length for its diameter: The higher the number, the longer the bullet. Generally speaking, the larger a bullet’s sectional density, the deeper it will penetrate.
VELOCITY
The third thing mentioned, velocity, also can have a large effect on a bullet’s performance. Velocity is often the culprit behind premature bullet destruction because as velocity increases, so does drag, and the tissue being entered gets “harder,” in effect, because it cannot get out of the way fast enough. A simple analogy would be the difference between stepping into a swimming pool versus diving into it from a tall diving platform.
https://www.hornady.com/team-hornady/ballistic-calculators/ballistic-resources/terminal-ballistics
P.S. I don't have a 91/30 Mosin anymore, but if the right M39 Finnish came by, I'd pick one up again.