Good luck finding those components honestly. I thought I saw cabelas had some retumbo online for sale, be prepared to pay for hazmat shipping though. Primers are also hard to find still. Federal 215 is the one to use IMO. I finally caved in to the notion that finding retumbo anytime soon is not going to happen, and grabbed some Re25. I've also heard Re33(fairly new) shows promise for the 300rum. I know a lot of guys shoot 180gr bullets out of the 300, but honesty you're wasting horsepower. Use the 200gr and bigger bullets and use that power you have in the boiler room. That is where she really shines especially with retumbo, Re25 and Re33.