I was doing a little thinking after the fact. This was probably the first "almost" apples to apples comparison I have seen of a 35 Remington to a 357 Maximum in a Contender.
The 38.5 grain load is a Maximum Book Load listed for a 35 Remington Contender, and it is a 100% Fill Load in the 35 Bullberry. That should be about as close as that gets.

Both Cartridges are using the same Hornady 180 grain XTP Bullets from the same box.

That gets us to the 1 Inch shorter 357 Maximum Barrel. The 1 Inch difference in barrel length probably cost the 357 Max a small amount of velocity. How Much?? I would venture a guess at 25-30 fps.

I would venture a guess that the 357 Maximum will only gain in popularity now that Starline is making 357 Maximum Brass. Barrels: MGM has pretty fair prices on the 13 Inch Max barrel for the Contender.

The 357 Maximum is:
A miser on powder consumption
Has 2 great factory bullets The Hornady 180 XTP and 158 XTP FP
Tolerable Recoil
Not a Pain to form cases for (35 Remington Rimmed and 357 H are)
Cheap readily available brass from Starline
New MGM 13" barrels are reasonable in price
Works well with H110, 296, LilGun, 300MP, and 1680 powders
Dies are cheap to reload it with, nothing exotic required
The Rimmed case works great in a Contender
It will also shoot 38 Special, 357 Magnum, and 360 Dan Wesson ammunition

Whats Not To Love about the 357 Maximum?

Bob