Getting old with a bad neck does not allow me to shoot anywhere near starting loads in my large caliber rifles. I have two old reloading books that got me started on reduced loads. Ken Walters' Pet Loads and Lyman 45th addition. You can look at some of their cast bullet loads as well. I have old books because I am old I am sure that some newer books will list these loads as well as on line. NEVER just reduce a slow burning powder that you might be using as it can create unsafe pressures. Powders I have used are pistol powders with a low charge such as 18 grains of Unique in a 460 Weatherby with a 500 grain bullet at approximately 1200 FPS. I have used 11 grains of this powder in a 30/06 Weatherby that I have with a 180 grin bullet. A newer powder that has come around is IMR's Trail Boss. Their web sight list appropriate loads for you to look at. Their might be a newer powder but then again, I am old Reduced loads with enough velocity and the correct bullet a lows you to hunt whitetail deer and even hogs a close range so don't sell those big bores just because, your getting old

In a Vanguard a 243 or 223 would be my choice. If you ever choose to hunt at long ranges the .257 will kill easily anything in the lower 48 Joe

I purchased a slimmed down custom once that would not shoot. I finally figured out that the front guard screw bottomed in the receiver before actually tightening down the receiver in the stock.