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Discussion Starter · #1 ·
I am using a set of digital calipers from a buddy. Not sure if they are accurate or not. ( Asked about Calipers in another tread).

Anyhow, can someone explain the position on the caliper you need to get your readings. I am not sure if his are accurate or not, that's why I had asked about a cheap way to check for accuracy.

I was also alittle confused about the Min and Max case length for a 30-30, preloaded. The reason I ask is I had some once fired factory brass that felll under what was in my Lyman 47.

I was a little cornfuzed about the drawing vs what was below in the specs.

What should my Min. and Max. case length vs finished loaded over all length. Tube Feed 336

All for 30-30


Premium Member
17,017 Posts

Hey Romans,

When you "close" your calibers, do they read "zero"? (one can measure a bullet's diameter, since you are loading for the 30-30, your bullet diameter should be .308")

Did you size your cases before measuring? (preferred method)

All cases "stretch" upon firing/re sizing. Some more than others.

The minimum length, is usually (depending on Manual) the "trim to" length.

The maximum length, is usually the length at which trimming is recommended.

The "normal" method of setting one's trimmer, is to select the "shortest" case in the bunch (say .001" above/below minimum), and trim all cases to that length. Most trimmers "index" off of the "head" of the case. (Lee is the exception, the Lee Trimmer indexes off of the flash hole)

This allows the application of a uniform crimp. (plus, chamfering the case mouth is very beneficial)

Hope this helps.

Later, Mark
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