Tuning P-Rod reasonable Expectations

Hello all. I am looking to buy or cobble together a small, lightweight repeater in .22 for plinking and small game hunting. I currently have a 2240 with some minor modifications that I really like, but it just doesn’t have the output I’m looking for to reach out to longer distances, and it isn’t going to without going HPA anyway.




The Marauder Pistol looks like the closest thing out of the box to what I’m looking for, but I would like it to operate at or as close to 20 ft*lb of muzzle energy as is reasonable. My question is, can this be done reliably, and if so, what is a reasonable shot count that could be expected at that state of tune? Where would I start? 


Also, for clarity, I am not legally restricted on performance in my location.
 
I can second Ctshooter. Once you get north of 16-17 FPE, efficiency goes out the window. It's totally possible to hit 20fpe, but only for one mag probably. I'm at 24 shots that stay within 4% ES of 700. My string runs something like 702-730-702 unregulated with the Bstaley o-ring mod. I have great accuracy to 60 yards with the H&N FTT in 5.54mm head size. I was plinking 1" spinners 22/24 shots today over 3 mags.
 
For the same amount of money, you can get the Kral NP03. It's a lot more gun and has much more potential and a vastly superior shoulder stock.

I have a Prod that with a MM barrel and moderator. I would trade it straight across for the NP03 in a heartbeat.

https://www.pyramydair.com/s/m/Kral_Puncher_NP_03_PCP_Carbine_Synthetic_Stock/4774

Bone stock outta the box shows 25fpe in .22 cal. No mods needed. Buy it, load it, shoot it.