MinnFinn

Well unless you know with certainty what powder Hornady loads in this ammo, you really can't safely duplicate with just the same powder weight. You could get a load that's too hot or too light (not safe), if you happen to use a different powder, even if you load the same weight.
I'd stick with the recipes of whichever loading book you find consistently gives you most accurate, best performing loads for whichever rifle cartridge you're loading for.

Akholland

Getting 6" groups at 100yd shooting Superformance ammo in my new 270 t3. Was great with light federal target loads.. first half of the box of Hornady was good and it's been poor accuracy ever since. Going back to federal and try again. Anyone else have bad luck with hornady?

Topgun 3006

Hornady Interlocks is all I use in the three calibers I reload and all are MOA or less. I can't remember the last time I bought any ammo at a store. Maybe you should try another line of their product that doesn't use that powder. I'm using IMR 4350 in my 25-06 and 30-06s and IMR 4064 for my .243.

bpd1982

AKholland
If half a box shot well then it went to crap it sounds more like a scope problem.