.40-82 bullet diameter

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13 March 2008, 23:36

Roberts99603

.40-82 bullet diameter

I have a square bolt 1895 Marlin. Made in 1896.

Anybody know my bore diameter?

As best as I can measure, it looks like .410, but would I sacrifice accuracy if I went for .409 or .408?

Bill Roberts Homer Alaska

14 March 2008, 01:01

carlos111

Roberts, this isn't going to be as simple as it might appear. The .40-82 uses a heeled bullet, like a .22 LR, so you need a bullet that is narrower at the shank than further out.

15 March 2008, 00:15

ireload2

quote:
Originally posted by Roberts99603:
I have a square bolt 1895 Marlin. Made in 1896.

Anybody know my bore diameter?

As best as I can measure, it looks like .410, but would I sacrifice accuracy if I went for .409 or .408?

Bill Roberts Homer Alaska

You need to get accurate measurements of the chamber and bore before you start anything.
You also need to verify the old bore is in good enough condition to bother with. Most likely your groove diameter is smaller than .410. Winchesters were supposed to be .406.
Cast bullets are recommended to be .001 to .002 over groove diameter. However the neck of the chamber has to be large enough to permit a larger than groove diameter to be seated.