Twist rate?

Thanks!

[Amish_Bill]

Gratuitously copied from a post by 4v50 Gary on The Firing Line (old or new TFL, I don't know)

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Until 1987, the Mini-14 barrel had a 1-10" twist. It was then changed to 1-7" to stabilize the new 62 grain military bullet. The old 1-10" handled the 62 grain satisfactorily, but wasn't deemed good for the new tracer round.

Law enforcement agencies primarily use the 55 grain bullet and the CA Dept. of Correction complained that their Mini-14s would hold a 8-10" group at 100 yards and a 1-2" group at 50 yards. Ruger dispatched its Chief Armorer (my instructor) who examined the guns and ruled out the ammo. CDC had a national match level shooter who demonstrated that their guns wouldn't group.

So, Ruger procured firearms from Colt and concluded that Colt enjoyed no advantage over the Mini. Ruger engineers then concluded that the twist needed to be changed and sometime in 1996, the twist was changed to 1-9".

What is the rifle twist rate in a mini14?