A long while back, I read this article on the Border Barrels website. They took it down a few years ago, but I hunted it down on the wayback machine - https://web-beta.archive.org/web/20110711132007/http://www.border-barrels.com/articles/art1.htm
Range Report More BC is always better ?
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Interesting read, thanks for posting. I guess there is a reason why FTR shooters are only using 185 gr and heavier bullets, with the 200 gr Berger being very popular. The 215 Berger also works well, even though the MV is low, it will still outperform a 155 at 3000 fps at wind drift. But FTR is static 1000 yard shooting, so a faster, lighter bullet might be better for PRS and similar events. But for pure LR shooting, I would say the higher the BC the better.
I agree. In my simple mind, I equate BC with efficiency. It retains speed better than a lower BC.
Another example is to compare a modern BTHP on the G1 vs G7 drag scale. Look at at the further ranges and notice how the G1 scale will start to show more drop than the G7. The two curves start to separate as the G1 doesn't recognize the efficiency of the higher BC modern projectile.
The point of the article is that there is no "reasonable speed". A 300 SMK at 2163 fps will out perform a 168 at 2866 fps. Drop will be higher, but wind drift will be less. As long as you know the range exactly, drop can always be dialed. So for known distances and prone matches where recoil is less of an issue, the heavier bullets are more likely to win. This is assuming the bullets have the same form factor of course.
Now in PRS style shooting, with barricades, and the occasional UKD range, velocity is very helpful.
Now in PRS style shooting, with barricades, and the occasional UKD range, velocity is very helpful.
Yup, the math doesn't lie here. I checked with JBM, even in a 308 a 230 Berger will drift less than the excellent 185 Berger, when they both are driven at the same pressures (I used 2700 fps for the 185 and 2400 for the 230). This is a known fact in the FTR game. The 230 woudln't exactly fit in a mag though.
All else equal, more bc is always better. Given that all else is not equal, it's still probably better. There is a tradeoff when you get to the very heavy bullets (200+ in a .308), where the gains aren't worth the increased recoil (a reason you see FTR shooters sticking with 185's even though there are ballistically superior bullets like the 215's out there). But in pure ballistic terms, high bc is always good, just as high muzzle velocity is always good. By the way, anything Kolbe writes is solid. The guy really knows his stuff.
It all depends on the powder used, to push to bullet and how good the bullet's transonic performance is in the end result at extended ranges.
This is very true. I guess I should have mentioned that it depends on the intended use.
F-TR shooters figured this stuff out yrs ago. MV is temporary, BC is forever.
Depends on range. The slower high BC bullets retain velocity and start to pay drift dividends beyond about 600 yards. Use the ballistics app of your choice and compare the velocity at 1000 yards of a 185Jugg launched at 2800 and a 200 Hybrid at 2650. The 200 is running a couple of hundred feet per second faster when it gets there.
Out to about 500 yards there isn't a whole lot of difference in performance of most and inside of 400 yards it's really just something to talk about on the internet. (which is why I personally find the whole long range high BC hunting bullet market such a joke since 99% of the guys loading them won't ever shoot past 250 yards)
Now for UKD shooting it's different because the faster bullets shoot quite a bit flatter in the middle to long ranges. The other component is recoil. even with supported 18# rifles most F-TR shooters have found that they start getting unacceptable vertical when bullets reach about 215gr. (most shooters are running the 200H or the new 200-20X from berger) The numbers show that the 230s, even launched slow, have a drift advantage at 1000 yards, but nobody that I know has been able to shoot them with the consistency to win. Laying behind the rifle for 20 shots + sighters 3x a day is just more recoil than anyone can handle.
Depends on range. The slower high BC bullets retain velocity and start to pay drift dividends beyond about 600 yards. Use the ballistics app of your choice and compare the velocity at 1000 yards of a 185Jugg launched at 2800 and a 200 Hybrid at 2650. The 200 is running a couple of hundred feet per second faster when it gets there.
Out to about 500 yards there isn't a whole lot of difference in performance of most and inside of 400 yards it's really just something to talk about on the internet. (which is why I personally find the whole long range high BC hunting bullet market such a joke since 99% of the guys loading them won't ever shoot past 250 yards)
Now for UKD shooting it's different because the faster bullets shoot quite a bit flatter in the middle to long ranges. The other component is recoil. even with supported 18# rifles most F-TR shooters have found that they start getting unacceptable vertical when bullets reach about 215gr. (most shooters are running the 200H or the new 200-20X from berger) The numbers show that the 230s, even launched slow, have a drift advantage at 1000 yards, but nobody that I know has been able to shoot them with the consistency to win. Laying behind the rifle for 20 shots + sighters 3x a day is just more recoil than anyone can handle.
Went to Applied Ballistics Seminar last November. We spent a great deal of time on this and Lag Time is what determines the actual drift.
Lag Time = Actual TOF - Vacuum TOF.
Vacuum TOF = range (in feet)/muzzle velocity
Muzzle velocity and BC determine lag time at a given distance. so theoretically a higher BC and higher velocity equal lower lag time BUT for different ranges the same bullet could give you different results.
When choosing what bullet to shoot in a competition for example, you must do some homework on what distances to expect and find the bullet that gives you the lowest overall lag time or have multiple loads for the varying distances and use the bullet that is best suited at that distance.
Like XTR said, inside 5-600 it doesn't matter much but beyond that it does. But I would think a higher BC is more important because it should be able to retain whatever velocity it has longer.
(Applied Ballistics for Long Range Shooting Appendix B Equation 5.1)
Lag Time = Actual TOF - Vacuum TOF.
Vacuum TOF = range (in feet)/muzzle velocity
Muzzle velocity and BC determine lag time at a given distance. so theoretically a higher BC and higher velocity equal lower lag time BUT for different ranges the same bullet could give you different results.
When choosing what bullet to shoot in a competition for example, you must do some homework on what distances to expect and find the bullet that gives you the lowest overall lag time or have multiple loads for the varying distances and use the bullet that is best suited at that distance.
Like XTR said, inside 5-600 it doesn't matter much but beyond that it does. But I would think a higher BC is more important because it should be able to retain whatever velocity it has longer.
(Applied Ballistics for Long Range Shooting Appendix B Equation 5.1)
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