I am having a .300 RUM built on a Rem 700 long action. The rifle is being built by a gentleman of great reputation and will have a 5 contour Lilja barrel, non-fluted, 27 inches long plus a muzzle brake.
He will develop a load for the rifle which will probably consist of: Remington brass, Federal 215 magnum primer, some unknown amount of Reloader 25 (I would guess in excess of 95 grains), and a 180 grain bullet--not sure which one, but it will have a BC of .511. He full-length resizes each time.
I asked him how many loadings I could expect with hot loads from the brass and he said he limits himself to 2X loadings.
First: How does that assessment compare to the experiences of other experts out there. Is two loadings about the most I should expect?
Second: How can I tell by inspection or measurement of the brass--at any point in its life--whether it might have one more loading left in it? I know of course to inspect for head expansion, cracks, dents, etc. but what--beyond that could be done?
Third: If a person backed off to approximately factory loadings, what kind of brass life should one expect from magnum cartridges.
I appreciate the input--all of my past reloading many years ago was with .223, .308, .270, and .30/06 and of course I got pretty good brass life out of those cartridges.
I don't load for the RuM, but I do for the WSM and I watch the primer pockets close. I also have some brass that has had more than 5 loadings and is still in fair condition. However I do think Win brass is a little better than Rem. JMHO
I used to re-load but now I "hand-load".
-- Well, at least I try --
Location: The rifle range, or archery range or behind the computer in Alaska
Re: Brass life expectancy.
Equal for equal circumstances, the 300 RUM will have significantly less case life than say a 308 or 30-06.
That said, there are ways to extend the life dramatically.
For max life, you would use a very tight chamber. When you use a tight custom chamber, the brass doesnt expand much. When resized, even FL, it doesnt move much. To add to the life, use a body die over a standard die. These are typically a wee bit bigger therefore size them a bit less. Then just neck size after body sizing. Next use the appropriate powder for the appropriate bullet and dont OVERLOAD them. For my 300 RUM, I use under max loads. I can get 3300 from the 180 pills without stressing my brass. I can get 3400 safely but it limits my brass life to a couple firings. At 3300 and using minimal sizing tequniques I get 6-7 loadings. It is easy for me to minimize how much sizing gets done because I use a very tight chamber and neck. The more it expands and gets resized, the faster it will lengthen and weaken. Minimize it and they will last a while.
Long range shooting is a process that ends with a result. Once you start to focus on the result (how bad your last shot was, how big the group is going to be, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.
I run straight neck die on my WSM brass. I have just gotten into annealing the necks also. Annealing helps to relieve metal fatigue from over working the brass. I use Win. brass and have fired 6 times before annealing. Seems to be holding up so far.
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If you find your self in a fair fight, your tactics suck!- Marine 1st Sergeant Jim Ryfinger
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Interesting information and my thanks, Gentlemen. I am especially interested in the fact, Michael, that you can increase brass life from 2X to 6X or more by a reduction of only 100 FPS. That corresponds (at least the 2X) to what my builder is saying about his own experience--he loads 180 s to 3400 and gets only two firings. I had been wondering if he was just being overly cautious, especially with someone he didn't know very well.
He, unlike you, advocates use of small based dies for his tight chamber and full-length resizes every time--after case-trimming to square up the brand new brass. My tendency is to want to go exactly with his recommendations, but I have a lot of unlearning to do acquired over many years (by that I mean the notion that neck resizing is always best when you can get away with it.)
Case life will depend on pressure and how much resizing you do.
I would recommend looking at www.6mmbr.com in the tools area and read on JLC Precision and Jim Carstenson who takes a redding body bump die($25), 10 pieces of your brass fired 2x and then hones the body die to fit your chamber. Then he converts it to a FL size die with neck bushings. Cost is about $80 and 2 weeks. Custom die for $100 with neck bushings.
This will match your chamber as close as possible, minimize sizing and then you have decide on max MV or max case life. Max accuracy will probably be somewhere below max MV and that will extend your case life some.
Learn to properly set up the die and only bump the shoulders back .001-.002 each time vs .006-.008 as many do.