Hi guys I bought some berger hybrids 180gr bullets with a G7 BC of .345 and I decided to run some tests on them at semi lomg range 625 yards to see if they would get that BC. I have a Hoover metplat trimmer and poining die, so I sort 150 bullets and there is .002" variance at the ogive, pretty good so far. I start to metplat trim them about .005" and then point them. So if theory is correct I should loose about 2% BC and gain lets say up to 8% BC, so were 5% gain on BC which would bring the BC of this bullet up to G7.362 BC.
Well I shot them out to 625 yards and was low about 1.5 MOA, so I come back look at my speeds from my chrono at 12ft and decide to put a chrono at 200 yards to see what speed I am getting out there. Then I run those numbers with my 2 average velocities and I come up with my ne BC for these 180gr hybrid Bergers and I am a little off Bergers numbers.
The BC I got was .327, so it seems they are not as high as I thought.
Has anyone seen the same thing with these bullets?
But as far as acurracy they are pretty good if I do my part and the conditions are good, i get Half MOA or less at 200yards.
And when I shot at 625yards the bullets went through a quarter inch of steel like it wasnt there. So I think it should be a good hunting bullet. I shoot a 7mm Dakota caliber, Stiller predator action, with a 24.5" Rock barrel 8.73 twist and my load is 74.5grs Retumbo seated .015" off the lands and I am getting 2979 fps avg with low es and sd numbers.
Let me know if what I did was the right, as I am pretty new to long range shooting.
Thanks
Elmer
Well I shot them out to 625 yards and was low about 1.5 MOA, so I come back look at my speeds from my chrono at 12ft and decide to put a chrono at 200 yards to see what speed I am getting out there. Then I run those numbers with my 2 average velocities and I come up with my ne BC for these 180gr hybrid Bergers and I am a little off Bergers numbers.
The BC I got was .327, so it seems they are not as high as I thought.
Has anyone seen the same thing with these bullets?
But as far as acurracy they are pretty good if I do my part and the conditions are good, i get Half MOA or less at 200yards.
And when I shot at 625yards the bullets went through a quarter inch of steel like it wasnt there. So I think it should be a good hunting bullet. I shoot a 7mm Dakota caliber, Stiller predator action, with a 24.5" Rock barrel 8.73 twist and my load is 74.5grs Retumbo seated .015" off the lands and I am getting 2979 fps avg with low es and sd numbers.
Let me know if what I did was the right, as I am pretty new to long range shooting.
Thanks
Elmer
