AZ shot,
The 25-20 SS is a nice, mild cartridge and has been chambered in relatively weak rifles like the Stevens 44 so I wouldn't be concerned if your Ballard is a cast action Ballard.
My first SS rifle was a Stevens 44 in 25/20SS and it was a very accurate rifle. I shot 86 gr cast bullets pushed by 2400 for about 1300 fps. It certainly is good enough for jack rabbits and ground squirrels. It also may be good for coyotes but it might be light for javelina.
In very old reloading manuals, there may be HV loads for the 25/20SS which people used in strong rifles like the Stevens 44 1/2 and Winchester HW. I would stay away from those loads as they are relatively high pressure loads.
Have fun shooting your new find.
