The one problem with old reloaders is they often fear to do things differently - and they believe that they know better than someone with
only 40 years of reloading experience. Practicing mistakes for 58 years does not make them right!
J/K SuperHornet Obviously you older dies and chamber were made correctly so following the die instructions works for you - such is not the case with many of today's cheaper products. But anyone who
has case life problems and still headspaces on the rim is just out of touch. If one reads the reloading manuals they tell you this, but the die makers say different. Confusing for newer reloaders.
GG - If your Marlin reloads will not chamber in the M94, then either the bullet is seated too long, the case headspace is too long, or the case is expanded too much radially. You need to find out which is the cause.
Your M94 chamber may be chambered shallow or the die may be cut too deep. Smoke the sides and shoulder of a few sized but empty cases and chamber them carefully, then check where the soot is missing. If the shoulder is bare and the case won't chamber, then the headspace on the case is too long and you may have to cut a small amount off the bottom of the die. I had to do this once years ago, although today I'd send the dies back.
Did you set the die so that it bottoms out in the press? This would insure that the die is sizing to its minimum headspace dimension. If the empty sized case shows the soot removed from the sides, then the die may be too large in diameter - the only soluton is a new FL die.
If the empty sized case chambers fine in the M94, then the bullet is either seated too long, or the crimp has expanded the case neck or shoulder too large to chamber in the M94. The 336 may have a larger neck or shoulder diameter.
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