Kind of a dumb question here but I cant find the info I need in my books. Lee modern reloading second edition and the Nosler reload guide 6. Both books only give max case length. I've reloaded these shells once before and the case is lengths on the shells are between 2.460" and 2.475" max length listed is between 2.494". I'm a little confused as to why the lengths are so diff. on this 2nd reload when the first reload I ensured all the cases measured 2.476 Any help or insight will be greatly appreciated. Just recently started reloading I still have alot to learn. However I am thoroughly enjoying the results from the first reloading. Accuracy is greatly improved it's really unbelievable.
minimum case length 30.06
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ranger335v
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Even as a noob, you have already learned a fact; Agonizing over consistant case trim length to a thou is pointless.
"I ensured all the cases measured 2.476" "In the beginning..."? The case length was 2.494 - a few, before you trimmed the case .018 + or minus it was/is recommended the case be trimmed to 'trim to length', for most cases that would be .010 thousands below max. length, then there the thought cases get longer when fired,, not always so, I have cases that shorten .040 thousands, as in chambering a case that is 2.494 long and fire it, when ejecting the case I find the case shortened .040 thousands, rational: DIFFERENCE, difference in the size of the chamber and the size of the case, before the case gets longer when fired for the first time, it gets shorter when the case fills the chamber, but that is a hard sale to a reloader because to most reloaders "TIME IS NOT A FACTOR" and then there is that fuzzy area of stretch and or flow and bump. BUMP? ME? I wreck-um.
Reloaders and bad habits: I could mindlessly pill the handle, raise the ram and size cases all day for a chamber I do not have, so I determine head space first as in determining the effect the chamber will have on the case when fired, by knowing the difference between the size of the chamber and sized case, when I have an option, I can size the case to off set the effect the chamber will have on the case when fired. AGAIN, I have M1917 with .016 thousands head space, scary stuff? NO! I add .014 thousands to the length of the case from the head of the case to it's shoulder "THEN' add .014 thousands to the length of the case, that leaves me with a case that is 2.508, that number does not exist in any reloading book of specifications.
For me there is no advantage to short cases, I want my cases to cover the chamber, again my favorite die is the case forming/trim die, with little effort I form cases that can be used to determine the length of the chamber from the bolt face to the throat of the chamber, and to me there is no such thing as bump, I wreck-um, I erase the shoulder and reform it as in part of the shoulder becomes part of the case body and part of the neck becomes part of the shoulder. The neck does not get bumped it is erased.
The instructions for the 'X' RCBS die is trim the case .020 thousands below maximum length and then it goes into rational, the rational goes on to say by the time the case gets too long? the case will stabilize, then in the other world of reloading it is said cases harden after 5 firings and 'little useful information can be gained from the fired case for the effect of pressure, and then the part about neck sizing 5 times after the first firing, THEN, full length size the case to start over, HOW? The case has been fired 6 times.
My favorite cases, cases fired in trashy ol' chambers
Wreck, rectify = change, bump sounds like an accident unless you are shipping on the seas near Main, New Hampshire and Massachusetts, then it become 'stove'.
F. Guffey
Reloaders and bad habits: I could mindlessly pill the handle, raise the ram and size cases all day for a chamber I do not have, so I determine head space first as in determining the effect the chamber will have on the case when fired, by knowing the difference between the size of the chamber and sized case, when I have an option, I can size the case to off set the effect the chamber will have on the case when fired. AGAIN, I have M1917 with .016 thousands head space, scary stuff? NO! I add .014 thousands to the length of the case from the head of the case to it's shoulder "THEN' add .014 thousands to the length of the case, that leaves me with a case that is 2.508, that number does not exist in any reloading book of specifications.
For me there is no advantage to short cases, I want my cases to cover the chamber, again my favorite die is the case forming/trim die, with little effort I form cases that can be used to determine the length of the chamber from the bolt face to the throat of the chamber, and to me there is no such thing as bump, I wreck-um, I erase the shoulder and reform it as in part of the shoulder becomes part of the case body and part of the neck becomes part of the shoulder. The neck does not get bumped it is erased.
The instructions for the 'X' RCBS die is trim the case .020 thousands below maximum length and then it goes into rational, the rational goes on to say by the time the case gets too long? the case will stabilize, then in the other world of reloading it is said cases harden after 5 firings and 'little useful information can be gained from the fired case for the effect of pressure, and then the part about neck sizing 5 times after the first firing, THEN, full length size the case to start over, HOW? The case has been fired 6 times.
My favorite cases, cases fired in trashy ol' chambers
Wreck, rectify = change, bump sounds like an accident unless you are shipping on the seas near Main, New Hampshire and Massachusetts, then it become 'stove'.
F. Guffey
Thanx for the info guys. I just want to make sure I'm building these correctly. So far i'm jst real impressed by how much more accurate they are compared to factory. I've always been interested in reloading just havent had the time to get into it. Fortunatly now I do. I'll let everyone know how my next range trip went over this weekend. Thanx again
I have a couple hundred 30-06 cases, and the shortest I've seen is about 2.473. As was indicated the industry standard max is 2.494, I trim if they're >= 2.492. My trimmer trims them back to 2.485. Anything longer than 2.494 can be unsafe as the mouth of the brass will enter the freebore of the barrel and will crimp around the bullet when chambered (and wont uncrimp when fired, holding the bullet back, causing unsafe pressures and accuracy problems).
I also recently purchased some "short" brass which would barely chamber, even after a full length size. My best guess is that the brass was fired in a *very* long chamber, pushing the shoulder a large distance from the base. Even after a full length size, the shoulder sprung back a bit. I think the lesson is that short brass will probably have a high shoulder, even after the first full-length size.
--edfardos
(first post!)
I also recently purchased some "short" brass which would barely chamber, even after a full length size. My best guess is that the brass was fired in a *very* long chamber, pushing the shoulder a large distance from the base. Even after a full length size, the shoulder sprung back a bit. I think the lesson is that short brass will probably have a high shoulder, even after the first full-length size.
--edfardos
(first post!)
JimKirk
Member
ed ...
My guess is that you don't have your sizing die ajusted correctly... short brass would not cause that problem.
Jimmy K
My guess is that you don't have your sizing die ajusted correctly... short brass would not cause that problem.
Jimmy K
1KPerDay
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FYI the Hornady manual says minimum trim length is 2.484"
dunno how vital it is... if you don't crimp I imagine it's not super-important to have them all exactly the same. But I trim mine to that the first time through.
dunno how vital it is... if you don't crimp I imagine it's not super-important to have them all exactly the same. But I trim mine to that the first time through.
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