Which sizing die?

Sevy

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Up until this point I have always fl sized for my 300 win mag. I was having some trouble with the die and did something stupid and screwed it up. I was wondering about neck sizing, read a little about it but would like a little more insight. From what i can find a belted case should be treated differently than a non belted case. Should I buy a new fl size and stay with that or give neck sizing a try? Maybe some pros and cons would help.
 

elf

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Belted cartridges headspace on the belt, but that has no effect on FL sizing. FL sizing means moving the shoulder back a few thous.You can buy a neck sizing die that will
do this or buy a set of Ski Ottos die shims from Sincliair. Simply place one of the smaller shims under the FL
die, run it up and check the shoulder set back. If not enuf, try a thicker shim. Do so until the empty case chambers smoothly.
 

Gord0

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I use a Lee collet neck die for my 300win along with a body bump die. They will chamber smoothly with just neck sizing for about 6 firings in my rifle with the load I'm running. After that I size the body and bump the shoulder back .002" and start the process again.
 

Sevy

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Thanks az shooter. I think the bushing does in that thread may be a little over my head. What Gordo is suggesting is more what I think I am looking for. Using a collett neck die should work the brass less and therefore it should last longer correct? If just neck sizing for several firings is annealing necessary?
 

Gord0

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It does work the brass a lot less. I have never trimmed in 8 firings in my 300win. They have grown around .003". I do anneal every 3rd firing, but it's because I have access to an induction coil to do it and it only takes a few seconds. I'm also not shooting hundreds of rounds at a time.
 

Sevy

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I'm thinking I may need to start annealing. I thought I may try to build one. So when you neck size for six firings, on the seventh does the brass not chamber, then you know it's time to set the shoulder back?
 

Gord0

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I'm thinking I may need to start annealing. I thought I may try to build one. So when you neck size for six firings, on the seventh does the brass not chamber, then you know it's time to set the shoulder back?
They would still chamber, but the bolt was closing a little harder.
 

Sevy

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Ok here is a stupid question. If I bought a neck die, can I use my old rcbs fl die with the expander and decapping pin removed to bump the shoulder when it comes time.
 

Gord0

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It would size your neck way too small. I took my old RCBS full length die, chucked it in the lathe, and ran a reamer through it. Now it won't touch the neck, and only size the body and shoulder.
 

Sevy

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Ok. I will have to get a body die then. I don't have a lathe. I appreciate your help.
 

Gord0

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No problem. Something to also check out is the Forster full length sizing die. It does a really nice job keeping things concentric.
 

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