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**Mal H** · April 23, 2009, 07:09 PM

Kendo, do you understand the process now with jdscholer's explanation?

What you are doing is determining the number of inches (X) the rod takes to make one complete revolution assuming the rod is following the grooves of the rifling fairly well due to the patch or brush pressing tightly in the grooves. That gives you the 1:X" twist rate.

alfack - that's not a totally reliable method. Many rifles of the same model were made with different twist rates. Not to mention that the barrel may have been replaced at some time.

A Ruger Mini-14 is a good example. It has come with twist rates varying from 1:10 to 1:8, maybe more.

April 23, 2009, 07:09 PM	#8
Mal H Staff Join Date: March 20, 1999 Location: Somewhere in the woods of Northern Virginia Posts: 17,067	Kendo, do you understand the process now with jdscholer's explanation? What you are doing is determining the number of inches (X) the rod takes to make one complete revolution assuming the rod is following the grooves of the rifling fairly well due to the patch or brush pressing tightly in the grooves. That gives you the 1:X" twist rate. alfack - that's not a totally reliable method. Many rifles of the same model were made with different twist rates. Not to mention that the barrel may have been replaced at some time. A Ruger Mini-14 is a good example. It has come with twist rates varying from 1:10 to 1:8, maybe more.