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I have the similar problem. My rifle has always suffered frim short case life- 2-3 firings. My brass stretches about .020" each time, necessitating trimming every time. I fire-formed new Winnie brass with a light load and bullet, then sized to the max that the head space can handle- stripped bolt closes by finger, but has no slop. (interesting, to make the brass .005 longer than just full sizing, I needed to set the die .020 from the holder.) Anyway, brass fits headspace, loads of 43.5 IMR 4895, 168gr HPBT, Win LR or Fed 210 primers. Primers are flat, brass grows .020.
Sak hmmm 67 barrel, headspace, lands, etc matches my Win spare.
I use the Win spare as a case length gauge, along with a depth micrometer. I have compared the two chambers last time the SAK was loose, various cartridges measure the same in both barrels. And sizing .005 loner than the RCBS dies full length to, and being just snug in the rifle, would mean my chamber is about right. Full length sized brass is a good match to several brand new factory loads- M80 ball, Musgrove, and FGMM. No function probs with the longer brass.
I had allowed my length to creep up to 2.835- still fit in the mag. But reading up on 'bullet jump', it seems seating to where the bullet touches the lands = an extra 7,000 psi. I seated a bullet long, inked the bullet, dropped it into the chamber, rotated to mark the lands, mic'ed the head depth, to establish land depth. Adjust COAL to suit the particular bullet ogive. 2.830 would be just touching. Last set of loads, I made the coal fersure 2.790, so a bullet jump of .040? No help, still flattening the primers, still stretching to 2.020.
Whaddya think, try a longer bullet jump? Shorten coal to 2.760? Any other reason for high pressure signs?
Next item would be chamber diameter. Both barrels, brass rattles around radially- like .010 ? Is a "Large Base" die available? I know shot shells have a 'small base' die.
Hey Art L., could shell diameter be the prob re: one of your questions about re-forming 30-05 brass to 308? How it is accurate first firing, but second + loadings are sub-accurate?
Sak hmmm 67 barrel, headspace, lands, etc matches my Win spare.
I use the Win spare as a case length gauge, along with a depth micrometer. I have compared the two chambers last time the SAK was loose, various cartridges measure the same in both barrels. And sizing .005 loner than the RCBS dies full length to, and being just snug in the rifle, would mean my chamber is about right. Full length sized brass is a good match to several brand new factory loads- M80 ball, Musgrove, and FGMM. No function probs with the longer brass.
I had allowed my length to creep up to 2.835- still fit in the mag. But reading up on 'bullet jump', it seems seating to where the bullet touches the lands = an extra 7,000 psi. I seated a bullet long, inked the bullet, dropped it into the chamber, rotated to mark the lands, mic'ed the head depth, to establish land depth. Adjust COAL to suit the particular bullet ogive. 2.830 would be just touching. Last set of loads, I made the coal fersure 2.790, so a bullet jump of .040? No help, still flattening the primers, still stretching to 2.020.
Whaddya think, try a longer bullet jump? Shorten coal to 2.760? Any other reason for high pressure signs?
Next item would be chamber diameter. Both barrels, brass rattles around radially- like .010 ? Is a "Large Base" die available? I know shot shells have a 'small base' die.
Hey Art L., could shell diameter be the prob re: one of your questions about re-forming 30-05 brass to 308? How it is accurate first firing, but second + loadings are sub-accurate?