Neck Sizing: Full or Partial

[CyaN1de]

I know this should probably be in the Reloading section but it pertains more to precision I think.

I was wondering whether Sizing the entire neck or only part of the neck makes a large difference in accuracy, pressures, etc.

Please explain your reasoning for either.

The reason I am asking is because I own the Redding Competition Neck Die Set with micrometer adjustable neck sizing and was curious what the reasoning behind the adjustability is and if people use it to partially size their necks.

 

[Obtunded]

Size the area in contact with the bullet.

 

[Mystic Precision]

I neck size to hold the bullet firmly in place. As you have likely read, I use the Lee collet neck die as often as possible. This sizes with the typical 4 to 5 thou giving very firm neck tension which can handle useage/mag without the bullet moving.

I have tried the very light neck tension common to some BR shooters. Had bullets knocked out of whack while riding to the range so have given up on this method.

I will use the Redding body die to bump the shoulder whenever chambering becomes too stiff. I want to feel resistance when the bolt closes so I know that there is zero headspace on my cartridge. (This is for target rifles which will not see rough conditions.)

Match ammo is usually run at elevated pressures and this ensures long case life - no where for the brass to go.

I DO NOT recommend partial neck sizing as this will allow brass to accumulate in that bulge eventually leading to the dreaded donut/restricting chambering. I want to size all the way to the neck/shoulder. Bushing dies don't always get right into the edge which can lead to the donut.

I always check to ensure that my brass/ammo is concentric (very low runout). That way the cartridge/bullet will align with the bore even if the neck is not touching the chamber.

There are lots of theories on amount and how far to size the neck. I like the KISS method that is always repeatable. The Lee die can never go out of adjustment nor change amount of sizing. That is the type of no brainer die I prefer.

Jerry

 

[444shooter]

Have you custom ordered any Lee collet dies?

 

[Mystic Precision]

Yes, send down a few cases and bullets with $50 or 55US. Wait and enjoy.

I phoned ahead just to confirm what their turnaround was like. Took 2 months.

Hornady will also do custom dies if you prefer more standard stuff. I think they are doing a custom bushing die neck size too. Contact to see what they are up to. I think they were around $90 to 100US. Still about 1/2 to 1/3 real custom dies.

Jerry

 

[444shooter]

I am assuming the cases are to be fired, and not resized? As for sending payment, did you send a MO or ??

 

[Max Owner]

Be nice to get a precision reloading thread stickied with good info in it.