Kellory,
reading what your basic wants are there’s no way I couldn’t recommend a stag 15 upper. It is the cheapest way to get into an upper that will shoot all the better quality factory ammo very well and should you decide to start handloading like you said it’s the cheapest route there as well.
You want to shoot a bunch you need to think about cost.
Nothing is cheaper and easier starting off than a 223 case and a hornady 75 bthp.
If you’ve never reloaded before you don’t need to get bogged down with resizing this or that. You also don’t need to get distracted with weight issue as you said “long range” and that frankly doesn’t lean towards light.
Yes that upper is heavy. You’ll note that most long range rifles tend to have some meat to them. But mine and all 5 others that I have seen and shot are very impressive for the money.
Many of those guys^^^ know their stuff and shoot more than I..but With your parameters I think you should stick with that upper and the best ammo you can buy. Then shoot..
Mine is a simple stag with a 16x SWFA and can assure you that setup has smoked many combos costing 5x as much
