My daughter and both of my grand-sons have used a 257 Roberts to kill elk on several occasions. All kills were made with 120 grain Nosler Partitions and 115 grain Barnes TSX bullets and all were 1 shot kills.
None of us have ever killed pigs, but elk running from 450 up to about 800 pounds fell to the 257 Roberts just fine when hit with the right bullets. So I bet you'd have no problems at all with pigs from 200 to 400 pounds.
