The powders mentioned already are those I favour in my .22Hornet/K-Hornet, and for sure are very useful ones. In particular I like H110 specifically in the straight Hornet but have been using Vactan SP3 exclusively in my 'K' which I would also suggest trying in your .17 Hornet. Meters like water... REALLY!... giving me consistent & high M.V's. Worth a try I would definitely suggest Philip!!
As for the bullets/projectiles (NOT Heads... Please!?) I use the 20gr V-Max in my own .17 Centerfire - the amazing (to me) but oft grumbled at by others - .17 Remington. I drive these teensy .17 Poly-tipped bullets along at ridiculously high M.V's, in the order of 4450f.p.s. (measured by me over a 'Chrony' Sky-Screen unit) and they perform admirably, giving me 1 1/2" or slightly less three shot groups at 200yds powered along with CFE223. Makes for truly excellent fox medicine and, if one wants to simply clear away excessive rabbits on young arable crop fields (ha!.. those were the days eh??) blows em up - LITERALLY - at 100yds or less, and simply jellies the internals in the roughly 100->250yds range or there abouts...
I haven't used them - YET - but I have read several glowing reports for the (Slightly CHEAPER) 20gr TIPPED 'Varmageddons'..... IF I am reading the bullet info correctly they ALSO have a slightly BETTER C.D. than the already Brilliant 20gr V-Max's. If, when I do give them a trial - as soon as this damned dreadful disease lets us out shooting again!? - and I find their accuracy is at least on par with those wee V-Max 'Grenades' then THEY will be the new, go-to projectile for my .17Rem'.. So that is another bullet you might give a SERIOUS trial in your .17 Hornet Phil??...
Meantime, Good luck with your new reloading project but above all, please Stay SAFE!...

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