Robert:
Welcome aboard! We will all try to provide you with as much information we have gathered through experience and research - and from discussions on websites like this one.
Since you are interested in participating in a hunter-oriented activity, HPR silhouette is the way to go. Specifically, Hunter HPR silhouette.
Silhouette shooting boils down to 4 fundamental elements that will develop you into a better shooter. They are, not necessarily in the proper order:
a) Proper positioning for shooting offhand
b) Trigger control
c) Self discipline
d) Developing a well-tuned hunting rifle and optimum loads for it
Other skills you will develop will be:
a) How to interpret mirage
b) Better estimating of distances and Kentucky windage
c) Better all-around shooting skills
For starters, your HUNTER rifle will preferably be a Remington, Winchester, Tikka, Sako or other reputable firearm in SHORT ACTION. The rules, as you have already read, limit the rifle's stock dimensions to follow those found in factory hunting rifles, limit barrel length to a maximum of 26 inches, barrel contour must be tapered and the trigger pull must meet a minimum of 2 pounds. Remington and Winchester rifles benefit from accurizing and action bedding, while Sako and Tikka rifles usually require no more work than adjusting trigger weight.
Caliber/Cartridge:
Since the you want to shoot consistently and repeated recoil will tire you out as the match progresses, caliber and load combinations that will reliably knock down the targets at all distances with a minimum of recoil are preferred. Popular calibers for Hunter class are: .260 Rem., 7mm-08 Rem., 6.5 x55mm Swedish, .308 Winchester. The 7mm Remington Bench Rest and .243 Winchester cartridges are also used, but they a marginal and tend to be too weak to reliably knock down the 500 meter rams.
Scope:
The most important requirement in a scope for this sport is for it to have the ability to precisely track elevation and windage adjustments. That is, the adjustments must be able to reliably move the point of impact to where you want the bullet to hit time-after-time-after-time. Good scope brands are Leupold, Weaver, Bushnell 4200, Redfield and others. Magnification is an acquired taste. Some shooters, like Dave Imas, who posts here, like using 6X while others use 36X. I use anywhere from 10 to 20X.
I'm sure other members are better qualified to give you advice on position and trigger control, since, as a lot of folks know, I am not yet an expert on those subjects :eek: nor in self-discipline, so I'll leave that as my $0.02 worth. :cb2: