I have en encore prohunter that i love, the problem is i have other barrels i use for it and I would really like to pick up a nice used backup muzzleloader. I see people selling them all the time, the problem is I dont know which are good ones and which i should avoid. Ideally id like something that would handle up to 150 grain charge (i shoot bh209), easy to get the breach plug out, and a 209 ignition system. What would be some good guns to be on the lookout for?

I don't recommend 150 gr of BH 209 in any muzzleloader designed for BP/subs.

While it is true that Blackhorn has a longer lower pressure curve than 777 I would not go over 140 grains which is close to the same max pressure as 120 of 777 and 150 of Pyrodex.
I would recommend a Triumph B&C or a Knight the recoil of that load could be a problem withthe wrong gun.

great trigger, finger removable breech plug, nice handling n shooting. Optima!

I cant imagine why you would need or even want to use 150gr of BH209 BUT if thats what you want.....save yourself the headache and get a smokeless ML like the Savage. At least then you will get the performance you seek for way less cost to shoot. Plus it will handle heavy BH209 loads just fine. The barrel is rated to over 100K PSI and BH209 wont even break 30K PSI under normal conditions.

Otherwise try a Knight DISC based ML or maybe even a T/C.

I would say knight disc with the NFPJ or bear primer 209 for BH209 for up to 120gr but the new ones go up to 150gr but would not go that high and you can adjust the trigger were you like it mine are 1LB 10Oz and has a good soild stock good luck

Get a 50 cal Thompson Center percussion model. They are fantastic guns and you could probably find one pretty cheap. Although you wont be using 150 grains of powder. Get a good scope and your good to go, or just use the iron sights. Just my 2 cents

i should have clarified, i realise that bh is different, i just meant id like something that would handle your normal 150grain blackpowder charge....i woudlnt load to 150 with the bh.

You'll probably find 150gr is not as accurate as a lighter charge of any powder.

What about an mk-85? Classic old school gun, yet still one of the best guns ever made. You could outfit it with a 209 setup if you like. The used market has some reasonably priced if you look around.