35 Whelen
Handloader
- Dec 22, 2011
- 2,216
- 425
Seams like I remember an old Outdoor Life article about " testing twist" so went back and found it. (2007) I realize that an 8 twist is recomended for these bullets but bought some anyway to try in my 243 T/C Venture Predator rifle,
Here is what Jim Carmichael, had to say when they tested some 105 Bergers in a 1/10 twist barrel:
"But there was still more to be discovered about the peculiarities of rifling twist. For instance, of the two VLD bullets that performed so miserably in the 1-in-12-inch barrel, the 105-grain Berger now grouped beautifully in the ½-inch range while the 107-grain Sierra lobbed 6-inch groups and made elliptical holes in the target. Why would two almost identically shaped bullets, both well-made and differing in weight by a scant two grains, perform so differently?"
Since my new Venture, has Thompsons unique 5 groove rifling in a 1/10 twist, I thought I would try Jims theory and "give them a spin" I will post my test results, to follow.....
E
Here is what Jim Carmichael, had to say when they tested some 105 Bergers in a 1/10 twist barrel:
"But there was still more to be discovered about the peculiarities of rifling twist. For instance, of the two VLD bullets that performed so miserably in the 1-in-12-inch barrel, the 105-grain Berger now grouped beautifully in the ½-inch range while the 107-grain Sierra lobbed 6-inch groups and made elliptical holes in the target. Why would two almost identically shaped bullets, both well-made and differing in weight by a scant two grains, perform so differently?"
Since my new Venture, has Thompsons unique 5 groove rifling in a 1/10 twist, I thought I would try Jims theory and "give them a spin" I will post my test results, to follow.....
E