Why is a 30-30 any different for crimping than any other calibre?
I am not a great fan of Lee dies, but mainly because of the mickey mouse way they hold the primer removal and internal neck sizing rod in place. Other than that, they seem to work OK. I have them in a few calibres and have no trouble crimping with them.
I am not a fan of their so-called factory crimp die. I was talked into getting it with the first set of Lee dies I got. But after giving it a good try I went back to crimping with the regular seating die, which I much prefer doing.
I have been reloading 30-30, off and on, for some thirty five years, always using RCBS dies. The 30-30 has crimped perfectly with regular dies, so why would it be different with Lee dies. Lee, like all reloading dies, are built to SAAMI standards.
I fairly recently started loading the 35 Remington, which after all, is just a 30-30 case opened up to 35. I bought Lee dies for the 35 and they tried to talk me into getting the special crimping die. But no way, I didn't want it. I have had 100% success in crimping the 35 Remington with the standard Lee seating die.
We also have to consider that guys were reloading the 30-30 for maybe 80 or 90 years, before Lee made their crimping die!
Taking all of the above into consideration, and with full respect for other peoples opinions, I'm afraid I have to consider it hogwash that a 30-30 won't crimp properly without the Lee crimping die.