Originally Posted by Bullet bumper
I invented a special technique for neck turning in a factory chamber called partial neck sizing . The reason I say I invented it was because I came up with it all by myself but others would have also done the same thing .
For a bolt gun if you only size some of the neck and leave an unsized second shoulder . You will avoid all the negatives associated with neck turning in a factory chamber . Use a Lee collet die to size the neck with a washer over the case to shorten it. Use a Redding body die to size the remainder of the case when needed but it will never touch the slight second shoulder . It stays a neat fit at all times . If it drags when chambering shorten the unsized section a bit . The die system reduces case neck hardening and the partial sizing reduces stress on the case neck while expanding and keeps the case centred no matter what other sizing is done .
I know 4 World champion shots that use this system .
I load every bolt action I have this way and skim turn the necks on every one.
Don't believe me ? Try it and see .
Hello Jeff, BB, and AZS,
For such a short thread there's been a ton of info here. I never cease to be impressed by the wealth of experience and knowledge in this group.
I am a padiwan when it comes to reloading and am always eager to learn from the Jedi Masters of reloading that we have here to guide us.
Questions I have are:
When you state "80 percent" are you referring to 80% of the neck length or neck thickness?
The partial neck sizing makes a lot of sense to me, albeit I am still a lowly padiwan. I use a Lee FL die and Neck Collet die and my 300WM is a 'factory' rifle.
How much of the neck is sized in this process and how would you go about setting up the die to size just a portion of the neck
When using a "washer", exactly what is it's purpose and where is it placed? I have seen 'shims' which are placed beneath the casing on the shell holder made by Innovative Technologies and specialized shell holders which are 'sized' to increase the shoulder bump. Is this also the purpose of the "washer" and how do you determine the thickness of the washer?
One last question: What is meant by "skim" trimming? I have an idea what is meant but I'm just not sure.
Ok, another question just popped into my head
: If you ream the necks in addition to neck trimming, would this process change?
I am very grateful and appreciative to you 'Masters' for sharing your wealth of knowledge and experience as well as your time and patience with us 'padiwans'