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How to determine twist

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26 November 2019, 08:08
LHeym500
How to determine twist
Is there an idiot proof way of figuring out a barrel’s twist.

I stress idiot proof.
26 November 2019, 16:37
farbedo
Cleaning rod with tape on it to form a little flag about halfway down, tight fitting jag and patch or brush, pencil or marker and a ruler.

Lay rifle on table, or put in cleaning cradle. Insert the cleaning rod into the barrel with the patch so it is forced to turn by the rifling. Mark the rod at the muzzle, push it in until the flag rotates on full revolution, mark the rod again at the muzzle.

Remove and measure the distance between the two marks.

Jeremy
26 November 2019, 19:07
dpcd
I do this; tight patch on the rod. Push it into the barrel. Put the tape on the rod. PULL it out until the tape makes one turn, and returns back where you put it (the flag). Meaure between the muzzle and the flag. That way requires no marking or other steps.
26 November 2019, 19:12
LHeym500
Thank you both.
30 November 2019, 21:20
Greyghost
All you need to do is put a small scribe mark on the rod up near the handle, and use a regular brass cleaning brush. Count the rotations as you push it through and divide number by length.

Phil