Was cruizing through an old Hornady manual(1980) the other day,They listed H450 giving the best vel.with 160gn pill for 7x57. Maximum was 2800fps. Barrel length:22" OAL:3.0"

ANy one else getting results like those above, or do you know other powders that will match or better H450 for Vel.without sending pressures through the roof?

Yes, H-450 has been the best powder to use with 160gr bullets in the 7x57. Not only does it provide velocity but outstanding accuracy also.
Even with the AI version H-450 is outstanding.
The same can be said for W-W 785, as it is the same powder.
It is a shame H-450/785 is no longer available.

I did H-450 and found it nice:
H-450 From 43.0 grains to 55.0 grains
Winchester WLR Primer

But my preference was:
IMR-4350 From 34.1 grains to 47.7 grains
Winchester WLR Primer

I used to use a bunch of H450, I ran out of it years ago. It will work in 7x57, .243, .338 and a bunch of others. It did however seem to vary a bit more from lot to lot than some powders in burning rate. Use H414 in your 7x57. If it's long throated, you can use as much as 50 grains for 2800 fps. I don't have it in front of me, but I think OAL on mine is 3.095. I've loaded enough of those I'm pretty sure that's right. It is about 63000 psi in mine with the pressure trace.

It is my understanding that H-450 was just a different lot of Winchester's WMR, which was a cleaned up W-785. Unfortunately, all thre have been discontinued.
I never used H-450, but did use W-785, and found that it fouled my barrels in a way that was hard to clean, something that did not occur with WMR, a powder I like very much.
Looking back over several loading manuals, it sems all three powders got short shrift by Nosler, Hornady, Sierra and Speer in as much as there is little load data for the powders. Hornady seems to have done some work with WMR. I have had good results with WMR in the .270 Win., .280 Rem., and .300 Win. mag., but not with the 30-06. I haven't figured that one out yet.
Paul B.

My experience with H450 was that it did not quite make the velocities Hodgdon published(no big deal), and it carbon fouled a bunch. Used up the single pound I had and never looked back. I think some of the Alliant Reloader powders are better in all regards. JMO

i hope you have a lot of it on hand as it is a very good powder in the 7 mm , just not mad anymore , when you run out , try thr relaoder sieries , as there is one very close to it now .