It is very hard to pin me down to "one" favorite rifle, since I have several. Which one is the flavor of the day depends a bit on the game and the terrain. Here are the ones I favor:
Custom 8mm Rem Mag. 700 Remington action, 26" Benchmark, 1-9.5 twist, McMillan Classic stock with Limbsaver, Triggertech trigger at 2.75 lb, Leupold VX3 4.5-14x40 B&C. .5 moa rifle with the 220 A-Frame, started at 3050, using RL26.
Custom 308 Norma Magnum: 700 Remington action, 26" McGowen 1-10 twist, Remington Custom shop Tiger Maple stock, pillar bedded, Limbsaver. Triggertech trigger, Leupold VX-3, 3.5-10x40 B&C. Also a .5 moa rifle. 180 Accubond at 3145, using Norma MRP.
Second custom: 308 Norma Magnum, Commercial Mauser Action, 26" Benchmark, 1-9 twist, Timney trigger, McMillan classic stock with Decelerator pad. Leupold VX-3i 3.5-10x40 B&C. Have shot 3.3" groups at 500 meters with this rifle. 215 gr LRAB at 2950 using Retumbo.
I have just acquired a 3rd 308 Norma built on a #1B Ruger action, but have not had time to load for it yet, since hunting season is here now.
There are 3 or 4 others that I like a lot but they see less action than the 3 customs Dave