I have quite a few(2 pistols and 4 rifles)hornets and do a bit of reloading for them.
I don't know about your "recipe" but I am curious about your choice of mag small pistol primers? Typically you just use small rifle primers and some use regular small pistol primers. The internal capacity of the Hornet case is pretty small and ignition of the powder is not a problem.
As far a tips for reloading the hornet, be very careful during bullet seating. The case neck of the hornet is very thin and it is easy to crunch a case when seating a bullet. The Lee collet dies work OK, you just need to make sure they size down the neck enough to ensure a good bullet grip. When you seat a bullet, try a push it in farther with our fingers. If you can do it then you are not getting enough case grip on the bullets because the case neck is not being sized down enough.
NJW in AZ