Before this thread is inundated with suggestions of everyone's favorite sling, I think you need to hammer out what you're looking to do with the sling. I understand that you're new to all of this so you may not realize the shear number of options that are available on the market now. I remember when we basically had a few options for slings but now we have slings that are quick adjust, some less so, some excel at shooting as a loop sling, others work better for shooting off of tripods. Some slings work better when used with AR-10's or AR-15's and other slings work better with heavy precision bolt guns.
For a heavy bolt action rifle I like a sling that is wider, generally 1.5" is about the standard, and I find that it supports the weight of the rifle very well. Lighter rifles like AR-15's and hunting rifles will do fine with a standard AR sling that is about 1" wide and features some sort of quick adjust feature. You also need to explore the features that a sling has and how that plays into it being used to provide the best support possible in a given situation.
For example, for use in conjunction with a tripod the sling should be quick adjust and have a loop that you can use a carabiner to clip in to. Once your rifle is attached to the tripod or resting in a saddle you can tension the sling and then crouch a little to provide extra tension and stability. For kneeling or sitting shots, this sling can also be utilized by slinging up in a patrol carry fashion and tightening the sling so that it's pulling tension across your back.
If you would like to use the sling more for support in sitting, kneeling, or prone positions then a sling that features a shooter's loop might be more up your alley. In my opinion, it's also better for a new shooter to start on this kind of sling since it will help instill the fundamentals of sling use that you can utilize across all of the other sling types. Again, for loop slings I like wider slings and having a quick adjust feature is very handy if you need to make a few small tweeks here and there while you're in position. Depending on what type of loop sling you get, they can also be used effectively with tripods too by running the sling down through the legs and connecting back to the buttstock. Tension the sling and it will help pull the rifle down into the tripod.
AR slings on bolt guns can also be used effectively but in my opinion they are a little thin for liking on a rifle that weighs over 12 lbs. AR slings are usually quick adjust and depending on the brand can be utilized as a loop sling as well in a pinch.
It's unfortunate but good sling use is becoming a dying art outside of a few specific disciplines.
Here are my recommendations for a few options based on the above.
Sling for use with tripod: TAB Gear PRS Sling. Expensive but an awesome sling that is very adjustable and very stable shooting off of tripods and barricades. It worked fairly well in sitting and kneeling positions too but to me not as stable as a traditional loop sling.
TAB Gear PRS Sling
Loop Sling: $ - Mountain Shooter Sling or TIS Slip Cuff Sling - Theses are no frills slings designed to be used as a loop sling to pass your arm through and use in a more traditional sense in the sitting, kneeling, or prone. They can be used with tripods with some adjustment and experimentation but a great sling to learn on.
$$ - Armageddon Gear PRS Sling - Probably my favorite sling for use across AR's and bolt guns. Lightweight, fast adjust, with bungee rear section to help take up the weight of a heavy gun. The loop sling portion is quick to adjust when going from different positions in a hurry and is pretty stable, even with a heavy 17 lb rifle.
Armageddon Gear PRS Sling
AR Sling: VTAC padded sling - It's not crazy expensive, I like the quick adjust that you can tension all the way up if you want to, and the padded section keeps everything comfy, even if you're carrying the rifle all day. If you want to use it as a shooting support, you can tighten the sling while wearing it in a patrol carry and it can pull tension across your back. Doing this I've been able to consistently hit a BC plate at 300 from the kneeling without much issue.
Hope this helped...good luck.
