The reason you can't chamber the case is because the shoulder is too long. You need to lower the die some, but without a way to measure it, it's a hit or miss kind of thing.
I like the Wilson headspace gauge, it is a good quick check that tells you that you are trimming to the right length and sizing the shoulder properly, unfortunately it still doesn't give you numbers, so that you can write them down for future reference. At some point you will need to measure it. That means buying calipers, bump gauge, caliber inserts, etc...
I hope you like tools, because reloading takes a few. What are you shooting? game or targets? Do you have calipers?
