You will get maximum penetration with the 158 gr bullets but also maximum recoil..............the 125Jhp will work but it might not expand well at non+P velositys at 830-860fps, while
the win 110Jhp silvertip at 880fps will mushroom but minimal penetration of 9-10" are the norm.
The BEST non +P ammo for the airweight guns is the 125gr NYCLAD by Federal if you can find them but they are not a "Winter load" that will penetrate a heavy coat or jacket well and give enough penetration.
You might need two of these low velosity loads to stop an attacker,maybe 3 or more depending on the conditions.......
One reason to at least think of a +P load when carrying or going to use it for SD, if possible. Light loads and a 300 pound enemy are not a good thing............