Aye, that’s kinda the secret beauty of RP: most damage possible in a “single” shot. If you really wanna get janky, and I strongly recommend it if you like the RP’s playstyle, you can stack up to 264% power on his crits: 1.25 (Crippling Strike) x 1.25 (Hunter) x 1.3 (weapon w 10% Power vs Chaos + 20% Crit Power) x 1.3 (charm w 10% Power vs Chaos + 20% Crit Power). You’ll obviously do less overall and you have to sacrifice Cruel Fortune but every 10s you’re a a howitzer. Imo, if you’re using RP this is probably worth it since there’s zero point taking ammo regen traits on the weapon. You’ll never reliably recover your ammo no matter how you slice it with RP so Prize Bounty is pretty much mandatory. This further yields that you’re not a slave to random crits, since you’re intentionally building to be a mobile delete key instead of a jack of all trades like we are with a Crossbow, so you don’t really need the crit +5% on the RP either.
Note: I suggested Power vs Chaos, like I do for almost every weapon/class on which Power vs is the preferred choice over Crit Chance, because a) they’re the only real threats in the game and have the only enemies tanky enough to make it worthwhile, b) RP will delete everything that’s Skaven w/o issue, c) The chaos monsters are the only ones you really need to worry about.
Edit: Again, against players of comparable skill you aren’t going to get many green circles with this build but that’s not to say you’re not having a real, practical impact by virtue of being the party’s “fixer.” It’s a pretty teamwork oriented build compared to Cruel Fortune + Scrounger + Crossbow