I've only owned my RSI in 7x57 for a relatively short time (since last August) and haven't had as much opportunity as I'll eventually have to "work up" reloads for it, but I'll give you my "results" along with my thoughts and feelings insofar as I have them at this point.
I love the "look" of the full Mannlicher stock on my little (total length = 36" with a 20" barrel) RSI. The rifle is trim and handy, but not exactly "light"... weighing in at exactly 8 pounds including a 4x-14x scope with parallax adjustment on the objective turret.
But that's relatively "light" compared to my Savage Model 99 in .300 Savage caliber at 9.5 lbs with scope & sling... or my pre-'64 Model 70 "Alaskan" in .338 Win. Mag. at 10.5 lbs with scope & sling.
And, frankly, a little weight isn't all that bad a thing when you consider that "weight" absorbs recoil. However, recoil isn't really an issue with the 7x57mm Mauser cartridge.
I bought my RSI from the original owner who indicated he purchased it in 1981 and claimed he put less than 1,000 rounds through the little rifle in over 25 years.
I have been reloading for over 45 years... and began to work up "accuracy loads" for my RSI last Autumn, but due to other circumstances, I only got out to my club's rifle range twice before the bad weather set in... and so I haven't completely developed "THE" most accurate load for sure as yet.
However, I did find out a few things about my RSI. First, it does seem to have a long "throat" since I am seating the 140 grain Sierra bullets out so far that only about 1 "caliber" (.284") of the bullet's base is held by the mouth/neck of the cartridge case... and the bullet is still about 40/1000ths of an inch off the lans and groves.
Second, my rifle seems to "like" H4350 rifle powder. Using a Sierra 140 grain ProHunter, flat-based bullet in front of various charges of H4350 sparked by standard Winchester large rifle primer in Remington cartridge cases, I found one "sweet spot" at 47.4 grains to 47.8 grains of powder (maximum load = 50.0 grains
FOR MODERN FIREARMS ONLY-Chamber pressure = 50,000 CUP)
However, there were other charges of H4350 between 47.4 grains and 50.0 grains (including 50.0 grains) that also shot very small 3-shot groups measuring an inch or less with 2 of the 3 shots often going into less than .2 of an inch.
All groups were fired at 50 yards from a solid bench-rest using a rifle rest and sandbags for support so I could be sure to hold the scope's crosshairs EXACTLY on the center of the bullseye. The scope was set on 14x with the parallax adjusted out of the scope at 50 yards.
All groups were measured with my digital calipers measuring from the outside edge of the two bullet holes furthest apart, then subtracting the bullet diameter (.284) from the resulting measurement.
As an example, the 3-shot group using 50.0 grains of H4350 rifle powder had a 3-shot group measuring .407 inches with 2 shots going into only .203 inches. Both muzzle blast from the short 20-inch barrel and recoil were up sharply from other loads, but cartridge case examination did not indicate excessively high pressure.
Estimated muzzle velocity was about 2750 fps based on a "known" chronographed muzzle velocity which averaged 2706 fps using the same components and 49.4 grains of H4350.
The single best group (size-wise) was achieved using 47.6 grsins of H4350 with the same components as above. The 3-shot group, fired on 9/21/06 measured just .270 inches with 2 shots going into just .176 inches. This group made a tight, inter-locking "3-leaf clover" looking group with a muzzle velocity averaging 2578 fps.
Other group's performance included:
47.0 grains = 3 shots into .564" with 2 shots into .109".
47.2 grains = 3 shots into .649" with 2 shots into .178".
47.4 grains = 3 shots into .522" with 2 shots into .071".
47.6 grains = 3 shots into .540" with 2 shots into .181" (this group was fired on 10/25/06).
47.8 grains = 3 shots into .880" with 2 shots into .052".
48.4 grains = 3 shots into .323" with 2 shots into .111" at 2641 fps.
49.0 grains = 3 shots into .372" with 2 shots into .101" at 2683 fps.
49.6 grains = 3 shots into .716" with 2 shots into .217".
50.0 grains = 3 shots into .407" with 2 shots into .203" (as given previously)
Naturally, you can't expect to achieve the same muzzle velocity with a 20" barrel that you can achieve with a 24-inch tube. However, for deer and even elk, a good 140 grain bullet at 2700+ fps is more than "enough bullet" to do the job if the bullet is placed accurately in the animal's "kill zone".
Throughout all the loads EXCEPT for the 50.0 grain load (maximum load for MODERN RIFLES ONLY), recoil and muzzle blast were mild. Cases showed little or no "stretch" and all cases came out of the rifle easily.
Later this year, I plan to work up loads using Winchester 760 powder along with 5 different primers and 4 different bullets in the 140 grain to 145 grain weight range. I also plan to do more testing using H4350 as well as IMR4320 and possible Hodgdon's Varget.
Before I began working up loads, I checked out all the posts I could find (using the Campfire's "FIND" system) on the 7x57... and there seemed to be a general agreement that the RSI rifles were difficult to be made to shoot accurately. Some owners went to great lengths to get their RSI's to shoot and then, only got "questionable" results.
While this is possible, I am beginning to form the opinion that the shooters may NOT have allowed the barrel of their RSI's to cool off properly before firing the next shot.
With all the wood surrounding the FULL LENGTH OF THE BARREL, it took my RSI at least
5 minutes sitting in the sun on an 85� day to cool down enough to fire another shot with a "still-warm" (not "hot") barrel. This was during my September outting.
By October, the weather had cooled considerably and I could fire a shot every minute or so on the overcast day I took the RSI shooting.
As a result of my research which indicated RSIs in particular were inaccurate and the older RSIs were especially inaccurate, I didn't think my 1981 RSI would shoot well, but... obviously, that assumption was/is incorrect.
Again, the results I got with my older RSI cause me to wonder if the other owner/shooters allowed enough time between shots to give the mostly-covered barrel time to cool sufficiently to NOT be affected by swelling up and touching the wood surrounding the full-length of the barrel.
I hope this lengthy review has helped you to form an opinion and possibly make a decison as to which #1 you wish to purchase.
Personally, I'm very happy with my little ol' RSI... it shoot well and I've only
BEGUN to "work up" loads with various components.
And something that should be of interest to you is the mild recoil of the 7x57 cartridge. You can shoot it all day off the bench-rest, even with fairly "warm" loads... and go home with a pain-free shoulder.
In addition to all of the above, my RSI with it's nicely figured #1 grade American burled walnut stock is just plain BEAUTIFUL, but then, I might be just a tad bit "prejudice".
Strength & Honor...
Ron T.