This wildcat is similar to the one Dan Lilja has, but has a 40 degree shoulder (PO Ackley).
Minimum body taper and a one bullet diameter neck. The action is a Jerry Geske in Superior, Montana. It uses a Remington trigger (Jewel with side safety) and takes a 1 1/8" barrel shank that's about 1 3/4" long. The barrel that Dan Lilja made for me is 34" long 1.350" at breech and 1" at the end. Its fluted 5/16"wide and deep with 6 flutes 27" long and has a George Vias brake. The stock is a McMillan prone with adjustable cheek piece and butt. Bruce Baer made the base with a 25 min. taper. It uses 4 leupold rings, a cant indicator, and cosine indicator. I use 2 bipods on it, a long Harris for sittings and a versa pod for prone. The finished weight is about 23# with the 8-32X56 Nightforce. I have about 1700 rds thru the barrel and have noticed a little decrease in speed. Sooooo... as far as loading data goes I have used the most WC872 at new barrel full power charge of 121 grs. With the 300 gr. Match king moly coated. Speed is about 3075 fps. I have shot up to 123 grs which got a little over 3100 fps. COL is 4.110". IMR 5010 with a starting load of 110 grs started at about 2930fps. 112 grs at about 1000 rds fired is about 3068 fps. I have used also T-5070, T-5050, and T-5020 powders which also gave good speed and accuracy. I have been using Fed. 215 and 215M primers, and have done some shooting recently with the CCI 250 and H-870 (about 114 grs) in a new rifle with the same barrel length, but a slimmer profile to fit a Ruger #1. Its shoots 3029 fps with a non moly coated 300 gr. Sierra. The molyed 250 grs go about 3350 to 3400 fps, and at a John Linebaugh shoot we tested a 250 gr. Hordandy FMJ went 3360 fps and shot thru 62" of wet newsprint straight. as far as the brass life, if you are careful during load development, I have fired some over 7 times. I have lost some to primer pockets getting loose, but the brass does not grow much at all. My 30-378 I had built in '79, brass grew about .020" per shot. The bolt gun shoots 2" groups at 400 to 500 yds prone off a Spec Ops drag bag. I have not really come up with 100 yd load that shoots less than about 5/8" for 5 shots, but it is relativity easy to hit with at long range, with the high BC bullets. I have tested Barnes TSX have good game anchoring ability, but with the lighter bullet weight the wind bucking is not as good. The Nosler Partion 250 gr go about 28" in the wet paper and don't shoot all that well. As we all know different guns shoot different bullets differently, even in similar rifles. These are just things I have done and for sure not rules or an end all in this field. Richard Graves and I were talking about 4 or 5 yrs ago, and I wanted to test some of his 330 Gr bullets. Richard was still having some trouble getting them into the USA, so I never have tested them, but read many good things about them also.