7x57 Mauser, SB M1000

[Cintax]

I have a Santa Barbara Model 1000 chambered in 7x57 Mauser. The gun is a great shooter with 140 gr Remington Core-Lokt. Since it is winter and I don't have enough to do already, I was considering hand loading the 'nearly prefect' hunting round. I'd like to have one load for Deer, Elk and Moose so I don't need to make any adjustments if I change bullet weight for larger game.

I measured the barrel using a cleaning rod and the barrel length is 21-5/8" from muzzle to bolt face (bolt closed on empty chamber). The rate of twist is 1:10. It seems to shoot 140 gr projectiles well enough as I mentioned earlier. Right now the gun is sighted in to be 1.5" above POA at 100 yards. Epps was out of the Remington loads so I recently purchased some Hornady factory loads (8155) that use a 139 gr Interlock bullet. They impact a little higher than the Core-Lokt round but much.

The Hornady ammunition is loaded with a 139 gr Interlock spire point with a reported 2680 fps muzzle velocity.
The Remington ammunition is loaded with a 140 gr Core-Lokt pointed soft point with a reported 2660 fps muzzle velocity.

I've also used some S&B ammunition but I don't remember how it performed. I do remember that the 173 gr loads were a bit stouter than the S&B 140 gr FMJ is tried ($19.99 per box when I was trying out 140gr).

Original sight in. I can't recall if this was S&B or Remington ammunition. I also can't recall the bullet weight if it was S&B then 173 gr if it was Remington then 140 gr. (2x power)

140 gr Remington Core-Lokt at 2x power

Photos of setup for the above targets

Anyways, I guess I have three questions.

1) Is it worth hand loading or should I stick with factory?
2) Does it make sense to have just one round for all game?
3) Does it make more sense to keep one load but alter projectile construction for larger game?

(Note: if these photos look familiar its because I have posted about this before in other threads)

 

[Boomer]

I am a proponent of handloading, the greatest advantage of which is not so much economic, as it is the increased versatility realized by your rifle. You can for example load cast bullets, or inexpensive jacketed bullets at 1200-1800 fps for small game shooting, or just fun plinking at targets of opportunity. Light weight bullets fired at high velocity, like 100 gr bullet at 3100 fps, are a devastating coyote load. Heavy round nose bullets are suitable for the largest game found anywhere. But since your search is for a single, general purpose big game load, its worth considering that the selection and quality of bullets available to the handloader, trump those of most factory loads.

The 7X57 is easy to load for, and in many examples tends to shoot well with a wide variety of powders and bullet weights. A 140 at 2900, a 150 at 2800, or a 160 at 2700 are all viable options for the do-it-all big game load, while producing flat trajectories for the ranges at which game is typically shot in Ontario, or elsewhere. With the excellent bullets that are available today, the old school rule of choosing heavy for caliber bullets for the best performance is less relevant today than it was a generation ago. Lighter bullets impacting at higher velocities, expand faster, create larger wound volumes, resulting in faster kills. At one time this was a recipe for shallow wounds, and lost game, but due to the new bullet technologies, a greater percentage of the original bullet weight is retained, and penetration is superior to that of the traditional cup and core bullets of similar weight.