I have both the Vortex 6-24 HST and the Zeiss HD5 that someone else suggested. Take my advice for what you paid for it
, but there are upsides and downsides to both.
The HST, I have mounted on my CTR as a long range fun gun/trainer. The Vortex is not great above 20 or so, it's usable but not great. It's also a huge scope. So far, it's seemed pretty accurate as far as adjustments go. And if you are not a dialer, the reticle is pretty nice, though the one on the PST, the hash marks are numbered, and I wish I had that. Up to 18 or maybe 20, the glass is pretty nice, not top of the line, but probably pretty great for what you pay for it. Keep in mind, everyone see's things differently. I have looked through all the top scopes and asked advice and find everyone has a different favorite.
To me, the HD5 glass is better, but not a world better. Where it pulls away is at the extreme end...that is my 3-15 is completely clear to my eyes at 15, it does not degrade. I checked out a 5-25 and it seemed (in the limited time I had it outside at Cabelas) very strong at 25 as well. So unlike the HST, the whole range is nice. It is also more compact. In addition, I think my HD5 is a little brighter than the HST at equal magnification, which is saying something since the HST is a 50mm and the Zeiss is a 42. They do make a 3-15 50 HD5 as well, I believe, the 5-25 I tried was a 50, but I did not get to try it in low light.
As far as adjustment goes, the 6-24 HST lists 65 MOA, I have 70 in the particular unit I have. The HD5 lists 75, I think, but I have 79 in mine.
I already had an HD5 before buying the HST, and could have gotten a 5-25 HD5 for not terribly much more than the HST, but ended up buying an HST instead of another HD5. Why? Well, it depends on what you want to do with it. My HST was for a long range trainer, not so much for a hunting rifle. For shooting steel, both work just fine for me in bright light, it's when it's really dim that the loss of resolution at the top end made a difference to me. But the HST has some things that are better for a target rifle than the HD5:
1) It has a much better zero stop system. The Zero stop on the Zeiss limits you to only 16.5 MOA when it's installed. IIRC, on my particular rifles, that gets me to something like 600 or 750 yards with a 100 yard zero. Something like that. That's fine for me for my hunting rifle, I can't shoot game at that distance, I am not good enough. But when shooting steel, I need to get out to 1100 yards, so that would mean running with no zero stop on the HD5, and I don't want to do that.
2) I like the reticle. Though I am a dialer, if I ever get the chance to shoot longer than 1100, I will need some additional elevation beyond what either scope can offer, and the HST has a better reticle for that.
However, as a hunting scope, it is my opinion that the HD5 is the better scope. I took it off my CTR and put it on my hunting rifle, a 300 win mag that will be mainly hunting but also limited play at the range. The reason I like it as a hunting scope is:
1) I think the range (verses a 6-24) is more versatile. 6 is too high the range of use I will put it to, and I have not hear great things about the 4-16 HST's, plus I don't think they will hold up against the HD5 in low light because they lose the objective advantage that the 6-24 had. In addition, the top end probably is not going to match either, so I like the HD5 for this purpose better.
2)The scope is more compact,
and all things equal, the glass on the HD5 seemed clearer and brighter to my eyes.
3) But probably one of the biggest thing for me is that with the lockplex, you get something I really want out of a hunting scope that I will dial with, and that is turrets that lock. You pull them up, dial your change, push them back down and they are locked. Zeiss has used this on their Victory line, Leupold used to do this on the VX7 (and now have a new locking model of the VX6), and Weaver does it with their Super Slams, I think. I know many do not worry about knocking the scope adjustments, or have system where they check it before they fire. But I have talked to many people who have knocked it unknowingly and suffered the consequences. When I asked Barsness his advice on this before settling on the HD5, he advised definitely covered or locked. So that's important to me, not so much to others.
So ultimately, I looked at both scopes, and bought them both for different purposes and reasons. They both have their strong and weak points. You might also look at the lower end Swaro line, their scopes are beautifully light and bright, but have some drawbacks as well. There is the new locking VX6 that looks like it will be a real winner too, but I think the prices are quite high on that one.
But for me, on a hunting rifle, I want a low range for very close fast shots, I want as high a range as possible because my eyes are old and I like magnification for long range, I want locking turrets, and as light as possible, and it needs to be as good as I can afford in low light. Oh, and tough. The HD5 fails on weight ( the Lockplex does NOT weigh 18 oz, only the regular models. I think it was more like 21.5 IIRC), but does pretty okay at the rest. And you can find deals on them if you call around. Doug put me in a new one for the same price as a demo.
So for a dedicated hunter in my price range, HD5 was my choice, but your eyes are not mine so YMMV.
Hope that helps!