Neck sized brass fit?

B

bingo

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How tight should neck sized brass fit, going into the same chamber it came out of. Should the stripped bolt simply drop on it, or should there be some tension when closing the bolt, and/ or what is considered optimum fit.
 
Depends on how many times the case has been fired and how hot the load being used is. Once a single case in a lot of cases is getting snuggy on closing the bolt it's time to FL size the whole lot of cases. I've come to the conclusion that FL sizing the cases every time is the best option. If the shoulder is bumped back ~0.002" the cases should chamber freely, case life isn't shortened, and you KNOW that ALL the cases for your rifle will chamber without any problem. After experiencing stuck cases out in the field prairie dog shooting I don't neck size anything anymore. The only exception would be in a low pressure load - maybe.
 
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Thank You Larry, full length sizing each time.... Interesting. How often do you anneal? I cut an AI chamber in .260 on my last build, and now am on the third firing, the first being the forming on the current brass, and noticed the bolt was a bit snug on the heads after neck sizing. I usually try my sized brass in the chamber to make sure it fits, so that is where the snug fit was showing up. I annealed it, full length sized, and trimmed the necks etc. and now the bolt drops on them. I just wanna know if that is considered good, bad, or in between for accuracy shooting or if I should try to leave just a bit of a snug fit. I get that you are saying that for field work like varminting, you think a clean fit is best, any thoughts on or is there a preferred touch for benchrest shooting?
 
I agree with Larry I FL size every time bumping the shoulder back .001". With a stripped bolt the they chamber with no drag. I have been doing this for a few years and it seemed to eliminate the occasional flyers that I had.
 
If the stripped bolt "drops" on an FL sized case you've sized the case too much. An FL die should be adjusted using a gauge that measures from the head of the case to the datum line on the shoulder, and set so that the shoulder is bumped back ~0.001-2". That sizes the case enough so that it chambers easily, but gives long case life. The less you can size the cases the better. Unless the chamber is oversized cases should last a long time depending on how hot you load. Cases will stretch and become harder to chamber with neck sizing and if the cases grow at different rates which is likely accuracy will vary between tight cases and those that aren't. With properly FL sized cases, assuming that the chamber neck isn't oversized, should last easily a dozen firings even with hot loads if good brass is used. I only anneal cases if they're being reformed by a large amount (necked way up or down or shoulders blown well forward). Unless you have a good annealing setup the necks can vary quite a bit in hardness after annealing too. Some believe in it like sunshine, others not so much or not at all.

If you're not using one I'd suggest an FL die with a neck sizing bushing so that the necks are sized the minimal amount. If you're not using neck turned cases you may still need a neck expander button, but if you're sizing the necks the minimum amount you can get by with the expander will drag a whole lot less and makes life easier for the necks. I used Redding bushing FL dies, for most of my live varmint rifles, and for my AR too. With minimal sizing of the necks seating effort feels very uniform with long heavy bullets in the AR's 5.56 rounds.
 
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