Also in case no one mentioned it.. when I used to shoot lots of powerbelts, I got better accuracy when I would, prior to loading, pull the plastic button off the bottom and put a little dab of bore butter on the lead spike. Oil or spit will also do. Then replace the button. The idea is to get that plastic button loose, so the conical will shed that faster. I have found some of them down range as far as 50 yards, which surprised me. I just seemed to shoot better groups with them. With 120 grains of Triple Se7en I am surprised you had any kind of accuracy. I get the best out of them when they are around 90-100 grains, but all rifles are different...
If you want an all lead projectile, try some of the maxiball (not the maxi hunter.. never could get them to shoot). They are 370 grain pure lead and if you were to punch that into an elk it should do a world of hurt on them. I buy mind from Black Jack Hill and then lube them myself with a home made lube. He also has REAL conicals. I just am not convinced that a REAL is a good choice for any distance over 100 yards. At least I have never proved that to myself.
http://www.blackjackhill.com/