- How do you determine what length of pull and comb height you need? I'm sure a lot of this is likely subjective and based on "feel" but are there general ranges for a shooters arm length or height etc?
The "cheat" to determining your approximate length of pull is to bend your elbow at 90 degrees, hold your hand with the tips of your middle finger and thumb touching (making an "o") and your trigger finger slightly straightened - such your forearm, back of your hand, and first bone of your finger are all in line, then measure from the crease of your elbow to the pad of your finger. That's a starting point.
The proper method is to use a stockmakers stock, adding shims to the buttstock and test fitting until the proper length is found.
- Pros and cons of varies grip angles and types? [...] I'm not sure how such grip configurations effect off-hand shooting and the type of shots a hunter will make.
Considering my injurious professional sport history, my wrist effectively dictates a vertical grip angle, whether that's an AR/chassis type pistol grip, or a gooseneck like the McMillan A3/A5. Vertical grips (supposedly) give up a little control and speed on shouldering for snap shooting, but they offer greater stability on the shot. One "con" might be the extra bulk, as the stock will be inherently more bulky due to the deeper profile. I prefer all of my rifles to have vertical grip angles, lest my wrist won't let me make good contact in my palm - and floating my hand away from the swept grip is NOT conducive to precision.
I snap a gooseneck or pistol grip stock to my shoulder just as well as anything I've ever fired, and carry through on moving targets just as well. It's a little less comfortable when slung across my back, so it almost necessitates flush cups on the sides rather than studs or cups on the bottom of the stock.
- Chassis system? And if so, which are suited to actual hunting/hiking and not just PRS type shooting?
Any of them can be serviceable - remember, our fighting men and women have been fielding chassis rifles, McMillan stocks, and AR types for decades with great success. Backpack hunters get too focused on minimizing weight and bulk, and I've played the role of "weight weenie" for my own backcountry hunting kit in the past. But it's largely over rated, in my experience. I ran an ultralight rifle for a decade, wobbled all over when trying to hold on game, and got the crap kicked out of me. I've found less disadvantages to running a well fit, standard weight rifle even for long excursions.
I recommended the MDT LSS originally in this thread, as it's a fine lightweight chassis, very suitable for a lightweight hunting rifle build. The Manners Precision stock would be the one which gets my money. The KRG Bravo you mentioned is more of a stock with a full length bedding block, not really a chassis, but it's a very affordable option among the elite stocks like Manners, MPA, and McMillan. That's why it weighs nearly the same. The McMillan Game Warden is a very light fiberglass stock - get the adjustable cheekpiece on this one, or any of the McMillan/Greyboe/Manners stocks you might choose. The game Warden is an A3 shaped buttstock and grip, with a rounded sporter forend. I wouldn't have bought one for myself, but after getting one on my Havak, I've ordered another GW for another hunting rifle.
Manners does offer a "mini chassis" in many of their stocks, which is a FANTASTIC option. I went with one for my most recent Defiance Deviant build. It's a true "bolt and go" chassis option, with a more traditional precision stock look and feel. If you decide on a DIY Remage build, this is a DIY friendly option for a precision stock. This is kinda like the KRG Bravo, a chassis wrapped in a stock, but a higher grade option.
The McMillan A3 & A5, Manners T2, PRS2, and T6 are my favorite rifle stocks. I prefer an angled stock for riding the bag, vertical foregrip, and I bounce back and forth between the wide belly of the A5 and the flattened forend of the others. I control the vertical pistol grip rifles far better on shooting sticks and other field supports as well. For my money, the McMillan A5, Manners PRS2, or MPA Chassis are what I'd buy.
OR...
You can have Macon cut you a beautiful piece of Walnut in any shape you like, and have a stock which is as attractive as it is functional. I mentioned my wife and my switch barrel rifles above - that's the route we went. Although, we did spend $1200 a piece just for the stock blanks, and about as much in pattern stocks and duplication, but the end result I've received from Macon has always been worth it!