What is the purpose of an expander die/expanding mandrel like Sinclair sells?
For everything I load I full length size and I am under the impression the FL die is the expander by default so I am confused as to what these dies/mandrels are for unless you are just going about this in a different way/method.
Right now I use Redding 'S' dies with the appropriate bushing in them. Is there any purpose in using this as prep or beforehand or is it just an extra step some people do, or do it only once for virgin brass?
For everything I load I full length size and I am under the impression the FL die is the expander by default so I am confused as to what these dies/mandrels are for unless you are just going about this in a different way/method.
Right now I use Redding 'S' dies with the appropriate bushing in them. Is there any purpose in using this as prep or beforehand or is it just an extra step some people do, or do it only once for virgin brass?