Interesting Case Growth

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It's interesting that the brass I figured was lowest quality seems to be the toughest.

.308 Win. Brass once fired (M14s)

Remington 150grn FMJ 0.015"
Winchester 150grn Powerpoint 0.020"
Prvi Partisan 150grn SP 0.002"!

Length after FL sizing is as follows :)confused: they don't make sense)

Remington 2.035"
Winchester 2.025"
Prvi Partisan 2.010"

Running the Partisan brass through my press also gets your attention as it takes a little more effort to size. Should the Remington and Winchester brass be trimmed? I am so confused with so many aspects of reloading bottleneck cartridges. Given the stories I hear I am scared ####less of destroying me\my rifle. Am I good to go ahead and finish loading the cases? What with the weird lengths after sizing? Thanks for any advice you all may have.
 
Brass will or can grow when full length resizing and will be different from lot to lot and brand to brand. RePete's advise is bang on.
 
I kind of got ahead of myself I guess. Can you trim primed brass? If not I guess I have a lot of primers to take out. What does a case trimmer go for? I didn't think I would have to trim my brass until I fired it a few times.
 
B said:
Can you trim primed brass?
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Depends on the trimmer. Lee, no. Every other one, as long as the primer is below the base (which it should be anyway), yes. In theory brass shavings could plug up the flash hole, but in reality this should not happen - just tap the brass out when you're done.

The most precise trimmer on the market is the Wilson, as made more usable by Sinclair - it's reasonably fast as well. The least expensive is the Lee. The most common are the Forster/RCBS/etc type that look like little lathes.
 
Probably not the best of ideas to begin with though. I wonder if the shavings could get hot enough to set off the primer in one of those "one in a million" sort of events.

acrashb said:
Depends on the trimmer. Lee, no. Every other one, as long as the primer is below the base (which it should be anyway), yes. In theory brass shavings could plug up the flash hole, but in reality this should not happen - just tap the brass out when you're done.

The most precise trimmer on the market is the Wilson, as made more usable by Sinclair - it's reasonably fast as well. The least expensive is the Lee. The most common are the Forster/RCBS/etc type that look like little lathes.
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B said:
Remington 150grn FMJ 0.015"
Winchester 150grn Powerpoint 0.020"
Prvi Partisan 150grn SP 0.002"!
Click to expand...

I'm curious, what were you measuring here? (was is the distance from the case head to the case mouth after firing, minus the same distance measured before the case was fired?)

There are two opportunities for a case to grow longer in length (the first is when it is fired, the second is when it is resized).

Your M14 probably has a 7.62mm NATO chamber, which are somewhat longer (in the headspace dimension) than .308 Win (this is to guarantee that the ammo will always freely load into the chamber, for reliability reasons). When F/L sizing according to the standard instructions (screwing the die down far enough to ensure solid contact with the shellholdeder), this will result in your brass stretching/growing 7-10 thou per loading. You'll have to trim your brass every firing or every second firing, and it will wear out (start to produce case head separations) after 5 loadings or so.

There are a variety of ways to avoid overly sizing your brass, though they either require extra tools (e.g. RCBS precision mic, Redding shellholder sets with different heights), or lots of fiddling (carefully setting up a controlled amount of gap between the shellholder and the die).
 
Those measurements are from top to bottom. First set was the difference in length after firing and the second set was OAL after FL sizing. Can anyone reccomend a better book on reloading than the Speer manual? There is a huge lack of detail in it and it is the cause of nearly all my questions and ####ups.
 
B said:
Those measurements are from top to bottom. First set was the difference in length after firing and the second set was OAL after FL sizing.
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OK - so what you've measured is the growth of your case furing your sizing process. (something to be careful about when measuring your as-fired length, is that sometimes the primer will have a small crater around the firing ping indentation. You want your caliper's jaws to masure from the base of the case, not from this higher ridge, otherwise you'll get an overly long reading)

Can anyone reccomend a better book on reloading than the Speer manual? There is a huge lack of detail in it and it is the cause of nearly all my questions and f**kups.
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Hmmm, Speer (#10?) is my least-favourite loading manual. Having said that, each manual has some sort of "how to do reloading" section; a lot of it is the same, but each one does add something new, often from a different angle. In addition to the alread-mentioned "ABCs of Reloading", I've also been happy with "Mettalic Cartridge Reloading" (the book that I learned from). Of my reloading manuials, my favourites are the Hodgdon one (for the wide range of powders given for each cartridge), and the Lyman (it has some weird/wonderful loads in there that you just don't find elsewhere).
 
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