Wondering if anyone else has had issues with Vihtavuori’s N140 load data and lapua D166 in their M39. I have a D marked vkt. From the manual I worked up 36-40 grains. The cases all produced low impacts and sooted cases. I emailed Vihtavuori’s support to see if they used a .308 barrel for this test 3 weeks ago and haven’t heard back. My cases are ppu fl sized and .310 expanded. I think I may try the .308 ball, might help with tension. This M39 has a long throat for sure. But still strange. This particular rifle shoots extremely well with Barnaul 200 grain steel case. It to uses a .310 bullet. I’m confident my rifle is very low mileage so I’ll rule any wear out or a shot out bore.
Vihtavuori’s Manual shows data for the d46 and Sierra both .308 so it’s hard to say if they have a lighter charge in the test barrel for the .310 d166. Seems weird.
Could start working past listed max and watch for
Pressure but worth a asking first I figure.
Vihtavuori’s Manual shows data for the d46 and Sierra both .308 so it’s hard to say if they have a lighter charge in the test barrel for the .310 d166. Seems weird.
Could start working past listed max and watch for
Pressure but worth a asking first I figure.
