Is there someone that could guide me on how to figure the rate of twist of my rolling block barrel.
Is there someone that could guide me on how to figure the rate of twist of my rolling block barrel.
Draw a straight line with a marker on your cleaning rod, full length..
Then using a tight fitting mop or brush/jag wrapped with cloth push it thru. Note when the line comes back to the starting position. 1 complete turn in 20" is a 1 in 20 twist ect.
Here's a link to a couple of tables based on the Greehill formula so once the twist is determined it can be put to some use. Many such tables exist on the net and in print. They provide guidance only. Actual shooting is the final test.
http://www.montanabulletworks.com/wst_page11.html
Here is another one. Pretty easy just plug in the numbers.
http://www.uslink.net/~tom1/twistrate.htm
Bob
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