Money, money, everyone wants to spend money.
Heck, simply turn your hat around backwards, put on some camo and go country. That is common sense....
Take resized case and a dremel tool and hook up the cut off blade.
Put the case in a vise firmly but don't crush it. Fire up the dremel and cut 2 slots from mouth to shoulder 180 degrees apart.
You could use a hack saw but my attempts with one were very poor.
Next, smooth the edges.
Then, slip the bullet of interest about half way down the neck and wiggle it around to loosen the neck tension.
The idea is to hand seat it really long then chamber it. The throat will seat the bullet barely into the rifling. If the neck tension is too tight the bullet will stick in the bore. If so, drop a smaller caliber bullet down the barrel and knock it loose. A short brass rod, of appropriate diameter, works also.
So far no money spent.
Ok here comes the money part.
You'll need a decent caliper. A digital one for around 30 bucks is useable.
Being as the idea is to measure the overall cartridge length you'll need a tool for that.
Those suggested are fine.
I use a Sinclair Nut which is a bit clumsy but very handy with no set up time. If using it remember to zero the caliper on the nut before measuring the cartridge or you'll be around an inch long in numbers.
You'll soon find that bullets from different manufacturers are quite different when measuring this.
The Sinclair Nut is also convenient for measuring seating depth adjustments.
Between the Nut and the Grip N Pull setting seating depth is darn near fun.
Don't worry about zeroing at any specific distance until you get it grouping, anywhere on the target.
Then zero it at the longest available distance that you can shoot, within reason, then work backwards to validate drops turns out to be way better, for me at least, than getting as close to spot on at 100, 200 or 300 then going long to validate drops/bc etc. Learned that from a Kirby Allen post not very long ago. Can't seem to find it at the moment.
HTH