So on the subject of .22hornet just some stuff I've lea d in the last 300 or so I've reloaded for my little gun.
Main causes I had when it came to crushed case necks and the like is either in sizing or bullet seating. Honestly the main deal when it came to sizes was the cast not being centered in the shell holder when ran it into the die. With larger cases it didn't happen as much because the mouths are bigger and the brass is beefier , you actually watch with some like a .308 , if it's not centered perfectly as long as the decapping pin get in they kinda "walk" over and get centered . .22 hornet can't really do that with the thin brass and small case mouth mor tomes then not if is not centered good enough the case will get a little size ways as you raise it up ans crush the neck. Just tanking a little extra time hold your case to the back of the shell holder is about all you need.
I would also lube them a little more thoroughly then bigger cases too. I found the hornady one shot spray line does a great job of quickly and easily getting in all the cases. Noticed my lube pad didn't work as well. Think it's because of the rimmed cases.
Now some people swear by neck sizing for hornet but ..eghhh, you going to have to full length size again eventually so I'd honestly just not mess with it. Though if you do apparently the lee collet dies are the absolute best bang for your buck.
Dirty dies will also screw you up so with the hornet so just clean you sizing die out every few reloading sessions. Doesn't take much maybe 2-3 min max but does help. Especially if you in a high humidity environments like me and you can get a lil rust in there without cleaning. Rust and grime cause friction with casual in needed stress on an already fragile case.
Now here the deal with case mouth or neck expansion. If your going to be using boattail bullets , I really wouldn't worry much at all past a good champer boatails basically self centered.... Flat base bullets how ever.... Yeah seating fault base bullet shas caused me the most issues out of everything really. You can definitely get away with a nice deep champher but honestly just like with loading cast bullets( which is 70% of what my hornet lives on) and any other flat bases bullet some kind of neck /mouth expansion just plain makes life easier. And with the price/ scarcity of hornet brass nowadays the whole $25 youl spend on a expanded due set up it worth it imo.
The lee is dirt cheap at like $15 max usually. And their stupid simple to use. All it is is a die with a little cone ( one for small calibers one for big calibers. That opens up the mouth of the case so you fat based bullet can get a better start. Take a soda can and sit in in a kitchen funnel and you'll get the idea. Works pretty good but noted you could still get some bullet getting seated a little cockeyed because the expansion isn't super deep.
Now easy fix for this is the expander plug from NOE kind athe same concept just does it deeper along with opening up the neck of the case a set about too. So you get a nice deep expansion that lets you bullet seat nice easy and centered every time again extra $24-$30 all together saves you some hard aches.
As far as crimping..... I just haven't seen much bed for it. I Mena I guess if your riding around on horse back or doing some navy seal stuff...other then that unless you just have super loose bullets I don't see the point most times...
O now one thing I would definitely watch out though is the bore of your barrel. Some older hornets shot a .223 bullet while newer ones shoot the .224 that other .22cals use