Re: More on my Wildcat bullet testing.
On the receiver screws, remember that overtightening then can be as detrimental to accuracy as loose depending on the bedding system you have in the stock.
For pillar bedded rifles I like around 55 to 65 in/lbs but have seen many rifles shoot extremely well down to 40 in/lbs as well.
In a conventionally bedded rifle, I limit things to around 50 in/lbs to prevent stock crushing as much as possible.
To be honest, I seldom use a torque wrench unless I get a rifle that is giving the owner trouble with consistancy. In a qality bedding, I have found that as long as the bedding is stress free, torque setting really don't make all that much difference. In a conventional inletted stock this can cause extreme variations though.
Onto bullets, I would be suprised if the 169.5 gr ULD RBBT did not have at least as high of a BC as the 175 Sierra MK.
Remember its bullet length and meplat design mainly that contributes to BC value, bullet weight has nothing really to do with it except that generally a heavier bullet is a longer bullet.
Best advice I can give is that if you want to see if they stay super sonic at 1000 yards, shoot them at 1000 yards and see how consistant they are.
Running your velocity numbers through my Exbal, I just am not sure what Abinok is talking about concerning staying supersonic to 1000 yards.
At 2550 fps you could use a bullet with a BC of .450 and still have a retained velocity of +1100 fps at 3000 ft altitude in 20 degree temps. With a .550 BC bullet you would have right at 1300 fps retained velocity.
With a .600 BC bullet you would be just a bit shy of 1400 fps. In fact with a .600 BC bullet you would stay over 1100 fps out to 1300 yards so I guess this recommendation confuses me a bit. Its not a trick to stay super sonic out to 1000 yards with any of these bullets to be honest.
Now I am not going to get into the exact BC value of this bullet. IF you recall, we got into a huge ******* match over this several months ago so I will say nothing of the bullets true BC and let you guys figure it out.
I will tell you though, at your velocity, you will have no problem staying super sonic to 1000 yards.
Make some more groups and see what happens!!
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