Re: neck sizing help?
Advantages are that theoretically you get increased accuracy due to a custom fit to YOUR rifle chamber, increased brass life due to not overworking the amount of expansion on your brass, and that its typically easier to neck size only. Remember you must full length resize virgin brass before you neck size but you could also reuse factory fired cases. The process is known as 'fire-forming' the brass to your chamber. This will give a custom fit of the brass to your particular rifle and must not be used in any other rifle. The shoulder of the brass should be a perfect fit ,or close to, your chamber and will serveto provide increased accuracy with proper reloading technique. In answer to your question, yes there are special dies you can buy for this purpose alone such as Lee collet die, or a Redding bushing neck die which are more expensive. Also, after neck sizing a few times (3-5) you will find the cases begin to be very hard to chamber in your rifle, this is because, even though your case is fire-formed to your chamber it still expands,(but less and less each firing) so you will need to either use a 'FL' sizing die to bump the shoulder back slightly or a body die (such as Redding) which will bump the shoulder without touching the neck. Hope this helps.