High BC but slow FPS vs. faster, lower BC bullet question

[Basic user]

Having to choose between say, Bergers 153 and their 140 in the 6.5cm; The heavier bullets have a higher bc but the 140 will get to the target sooner. I know shot group size kind of trumps most every other attribute but which attribute here helps with bucking the wind at a 1000 better, the BC advantage of the 153 or the shorter time of flight of the 140?
Anyone try both at a grand?

 

[BobinNC]

Perhaps this can help:

Form Factors: A Useful Analysis Tool

Looking over Berger's BC Form Factors the lowest BC Form Factor is held by the 6.5 mm 144 gr LR Hybrid Target @ 0.879. From that theoretical standpoint, that would the one I'd choose if I was looking for the "best" 6.5 CM bullet for long range.

The 144 gr LR Hybrid should deliver the best combination of both wind bucking and velocity of all Berger's 6.5mm lineup.

 

[Doom]

You can use a ballistic calculator yourself to see what the difference will be. Try JBM own the internet.

 

[Basic user]

Will do.

 

[CK1.0]

JMHO but if this is for long-range I wouldn't worry about which one will buck the wind better...

Of course, we all want first-round impacts. But the real name of the game is making good corrections, and for most of us, more feedback downrange (more splash, and/or being able to tell which way a plate rocked) makes that easier. So, in general, bigger is better for that. Not to mention the benefits that more time of flight and/or being able to use a smaller powder charge may add to the equation.

Speed means nothing IMO. A rifle can be just as accurate at 2550fps as it can be at 2750fps, it's almost always the monkey pulling the trigger that matters the most and makes the biggest difference.

 

[supercorndogs]

Speed makes a diffrence when choosing a bullet. There is a reason most shoot 155-178 range in the 308, and thats because it's tough to get a 215 or 220 bullet going fast enough to take advantage of the extra BC. A lot times the lighter bullets will out perform the heavier ones for 600y or so due to the extra velocity.

put them in a Calc, look at the wind at the distances you plan to shoot. If you are worried about how hard they hit the target look at energy too. Most calcs will list enegery.

I know have seen lowlight post "light is right." I think a lot of guys are finding the advantages of a lighter bullet going faster.

 

[Basic user]

Yea I hear that; I'm guessing that's why Palma guys push a 155 grainer as fast as possible. Is that because theres more advantage ballistically? Or was that because that's just the mandated weight and that's the rule?

 

[Basic user]

Perhaps this can help:

Form Factors: A Useful Analysis Tool

Looking over Berger's BC Form Factors the lowest BC Form Factor is held by the 6.5 mm 144 gr LR Hybrid Target @ 0.879. From that theoretical standpoint, that would the one I'd choose if I was looking for the "best" 6.5 CM bullet for long range.

The 144 gr LR Hybrid should deliver the best combination of both wind bucking and velocity of all Berger's 6.5mm lineup.

I actually just shot a batch of those, and they dont group as wel, though I just loaded one ladder. I should keep experimenting with those then eh?