I've shot different rounds from 110 gr down to 70 gr in this rifle, and it seemed to like the lighter loads. So question
Is, if shooting an 85 grain bullet (which is what I'm going to shoot), what would be the preferred powder in the .243? I've got a few powders that may work, but I'll go buy more if any of you have a good recommendation. Thanks for any help.

Would H414 work alright? I have 2 lbs of it and just saw it lists .243 on the label

90gr Nosler accubonds and bt with 4350 and varget have worked well in mine.

85gr partitions over 414 powder worked well in the mowhawk I had

Tipps, that's a great question. A lot of shooters don't approach it in your manner. Somewhere in the 4350 burn rate is about ideal for the 243 pushing the 80-90 grain bullets. You can go a little slower or a little faster and still be just fine. Here's a burn rate chart to give you a visual of other powders that also fit in the area of powder burn you are looking for. Some powders not on this list are Alliant 2000MR and 4000 MR. 2000 MR is slower than Varget, but faster than 4350, and 4000MR is close to a 4831 burn rate. Those 2 Alliant powders are a few "secret" powders that I really like.

And yes your 414 is a good powder for your 243 Win combo. I don't use it since it's a ball powder and temp sensitive, but it will work just fine for hunting applications.

https://www.hodgdon.com//wp-content/uploads/2017/01/burnratecolor.pdf

Lots of bullets will work, but the 80 gr Barnes TTSX really has an edge on big deer and pigs from my limited use.

39 - 42 gr of your H414 should work fine with a Barnes 80 gr TTSX.

I use 45.0 gr IMR 4831, F210, in Lapua brass, just because it was on hand, tried it and it worked well with mild recoil.

Echoing what others have said. I went with IMR4350 in mine.

Thank you all, I appreciate the help. Thanks Chad for the burn rate chart, that's a nice reference. I'm going to shoot a few with the H414 and see what happens, then might try 4831 since I have 2 lbs. of it on hand. If neither one of those works, I'll go get some 4350. Again, thanks a bunch.

Glad to see a Mohawk alive and well. I have a 600 chambered in 35 Rem and love the rifle.

I hunt with one in .308

85 grain Sierra HPBT and a stiff load of IMR 4350 with Win primers.