I am putting parts together for my first custom hunting rifle. I am starting off with a Stiller Tac300 action with a Krieger #6 contour barrel chambered in 300 WSM sitting in a Manners MCS-T stock. After talking to a few gunsmiths, a detchable mag system is probably not going to work for me. So I am trying to decide on what internal mag system to use. So far I have found Pacific tool and guage bottom metals, factory Remington bottom metals and Wyatt's internal boxes. Anyone have an opinion on what combo will work best for me or maybe another company that I need to check out? My next issue is what barrel length to use. Since this is going to be a hunting rig, I dont want the barrel length over 26". I plan on installing a brake, so that will add about 1.5" to whatever I use. I thought about going between 22-24" but i want to get the most speed that I can get while still having a rifle that I can easily pack around. Any thoughts/opinions? Any help appreciated.