I have a Ruger No. 1 in 7X57. My favorite load is a Barnes TTSX 140.0 grain bullet and 47.0 gr H4350. I have used this in Africa on several plains game including larger ones like blue wildebeest and gemsbok. All one shot kills.

Great all around deer bullet is the Sierra 140 btsp over either 4320 or 4895

I have seen two problems with the Ruger #1 in 7x57. First, some of the chambers are not very good. Second, they used the full length "international?" forend on a lot of them. Either or both of these issues may reduce accuracy. YMMV. The 7x57 cartridge, however, is excellent.

The secret for my 7mm Mag was to add pressure between the front of the fore end and the barrel. A few pieces of tape, I think.

Thanks to all for you helpful replies.  This is my second no. 1.  My other is a 7mm mag.  I have had it for 30 years and it has been a real favorite of mine.  I haven't made any modifications to it as it was out of the box "okay"  not good but okay.  After reading all I could about the issues with the no. 1's, I am apprehensive about firing it for fear it may be a problem child.  I've had enough of those.

I'm partial to controlled expansion bullets. Nosler in my case. 
One, and only,  experience on elk was a 243/85 gr. With such a light rifle on has to
place the shot right and limit range to about 125 yds. 
Nevertheless broadside shot broke the shoulder messed up the lungs and put the elk down. Elk got back up and moved about 20 yds shaking badly. Second shot
clipped a rib going in and left a 1.5" exit hole in the neck. End of elk. 

I'm certain a 7mm would have gone right thru but it might have still needed the 2nd
shot. Hunters lose elk with 270's and '06.

Just my opinion but I think I'd go with a 140 gr. There is a slight gain in 300 yd
energy with the 140 vs 160 gr. Maybe flip a coin.

I started hunting with a 7x57 in a Model 93 Mauser when I was 11 years old.  In those days Remington factory loaded a 175 gr round nose bullet at a little over 2400 fps.  That combo was deadly on the blacktail deer and I really should have stuck with it but as I got into high school I pleaded for a 30-06 like everybody else was using.  50 years later I have gone back to the 7x57 and my bullet weight of choice is 160 grains.  I acquired a Ruger #3 a few years back with a custom stock and barrel in 7mm Ackley Krag that shoots 1/2 moa when the load is tuned.  It has the set screw fix on the forearm.  The 160 grain Speer has dropped two hogs with one shot each with that rifle.  Somewhere over the last 60 or 70 years we have all forgot that many animals were killed with 30 caliber rifles shooting heavy round nose bullets up to as much as 220 grains.  The 7x57 is an enjoyable round to shoot and in a #1 can be throttled up to some pretty impressive figures.  My vote would be a 160 grain bullet sighted in 3" high at 100 yards.  If the animal is 650 yards away, do what hunters have done for generations, stalk closer.  My two cents worth.  Tom