Many, many years ago when I was but a young lad and the earth was still flat I did a lot of rabbit hunting with my Remington 600 chambered for the .350 Rem. Mag. The load I used was what its inventor, the famous gun writer C. E. "Ed" Harris, dubbed "The Load." I didn't have a chronograph in those days but the velocity it produced with 158 grain Speer .357 pistol bullets would definitely be less than 1800 fps, below your targeted range, but a helluva lot of fun to shoot with the very much reduced recoil and muzzle blast. Higher velocities can be obtained by using a soft cast bullet (say about 18 brinel hardness), instead of jacketed, and those bullets at about 1500 - 1600 fps are adequate for deer hunting at close range, say about ≤150 yards. I'm currently woking up some reduced loads for my .348 Win. and 45-70 Gov't lever guns using the Hi-Tek coated bullets from the Missouri Bullet Company and Montana Bullet Works which, at the reduced velocity produce very little, if any, leading of the barrel.
Anyway, Ed's "The Load" was 13 grains of Red Dot pistol/shotgun powder which is not at all sensitive to position, relative to the primer, and is bulky enough to avoid ever having a double charge by a simple visual check prior to seating the bullets. Ed says The Load is suitable for any cartridge of .308 Win case capacity or greater and with 30 caliber or greater bore when using bullet weights that are normal to the chambering. I have since carefully worked up similar loads using Red Dot, Unique and Blue Dot powders in cartridges of slightly smaller case sizes and calibers. You might carefully try those Alliant powders and see if you can safely work something up to your 1800+ range.
The latest updated revision of "The Load" by Ed Harris (1994) can be found at the following website where there is also another of his articles about the use of powders such as Reloader 7, 2400, 3031, 4198, 4227 & 4895 in reduced loads that could be a good starting point for getting your buddy's .350 up to the 2000 fps level. But if your friend's rifle is a Rem. 600 like the one I used to have you'll want to go with the fastest burning powders that work well, to avoid excessive report and muzzle flash from the short little barrel!
Here are some articles I pulled from the internet. Sorry about the length but folks have been asking for info like this. Mike "The Load" is 13 Grains
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