The Sendero is a great starting point, but can be quite pricey. It isn't always necessary (especially if ordered from the custom shop), but sometimes accurization is necessary to really get a Remmy to shoot. That is to have the stock glass bedded, trigger work done, and a lot of guys get the action tuned. Not sure if you have looked into Savage rifles, but they offer a pretty good line of rifles that will lessen the bill and allow for more money to be used toward better glass for your rifle. They have a new model Savage Arms Firearms > 111 Long Range Hunter
that is in the one caliber you are looking for. For target shooting at long range and even hunting, the 300 Win Mag will get you there with proper reloading. There are a few ammo companies that provide high quality ammuntion for sale that will do what you want, but to take this sport seriously one should really consider reloading. This will help to reduce the cost of ammunition and accuracy will be second to none against factory ammo.
The rifle I have suggested provides some great innovations to the rifle shooter starting out in long range target and hunting. It comes with the new Accu-stock, Accu-trigger, Muzzle Break, heavy barrel, and adjustable cheek rest. The stock has a fully integral aluminum bedding block offering a solid platform. The Accu-trigger is fully adjustable by the gun user from 6 to 2 pounds without any gunsmithing knowledge necessary. It usually comes from the factory at its lowest setting and in my opinion a very crisp trigger. They do offer other models in their tactical line that provide good aftermarket stocks on their factory rifles. The McMillian A5, Choate, and H-S Precision are the 3 that are used. They too also have a custom shop that would allow you to have any caliber put on your rifle that you should want.
I wouldn't suggest the RUM for target shooting. Barrel life is going to be very short compared to the 300 Win Mag and recoil will be much greater also. They do offer some varmint models that you can have barreled in what ever caliber you want also. Another advantage to having a Savage is ease of use. Should you want to make a switch barrel rifle, then it is pretty easy with a little bit of reading and the proper tools offered by many distributors allows a person to make different calibers on one platform. Other models are the Model 12 line and deffinately look at the tactical rifle line. There are a few pricey models, but should be worth the money if you are not on a budget.
Another aspect of long range shooting is the optics. It is wise to purchase the best that you can afford. You will thank yourself later. Good rings, base, and scope can go a long way in your ability to see in bad weather, and clearly at long range. I hope this helps and welcome to LRH!
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