Yes BC is very relevant at longer ranges. And some modern hunting bullets are becoming very good, lessons learned from the target shooters perhaps.
When really good monometal things in target calibres like .338 Lapua Magnum emerged, range safety distances had to be re-considered, HME rules introduced etc. I recollect that there was an unfortunate incident at Bisley when one was found stuck in a school windowsill, miles away, but I don't recall the exact details.
They also have to be manufacturable at reasonable cost, have good terminal ballistics over their useful ranges of distance and velocity, possibly be lead-free, have an ogive profile that is not fussy about seating depth, actually I think it's a lot more complicated than designing a simple target bullet, and we are blessed to have so many choices these days.
BC, be it 1,2,3,4,5 etc is actually a useful approximation. Perhaps with modern computational fluid dynamics you could get a better grasp.
en.wikipedia.org
Then there are genuine things to consider, such as the direction of your rifling twist, the more common right-hand twist will cause the bullet to lift significantly in wind coming from the right, or drop if it is from the left, for example.
Humidity, air pressure/altitude, temperature. Humidity is a big one, I've seen people having to make major 'scope corrections as the day warmed up and became muggy
Then coriolis. If you are shooting say .50 BMG, a relatively slow round, at 2km it even makes a difference shooting on the North-South axis laterally, if East-West in vertical. The Earth is spinning at about 1000 mph, 1470 fps, at the equator, zero at the poles. Very very simplistically put, not actually correct, when the bullet leaves the barrel, the Earth (and the target) revolves beneath it whilst it travels. It's real, and taken into account in advanced gunnery calculations.
But, hey ho, zero 1" high at 100 yards in the traditional manner, convince yourself that you can get three shots into 1", after a few attempts, stalk close, point and shoot and call it good enough.
Or carry a laser rangefinder, a Kestrel, and mobile phone app. Great on the range, not so much in the field. Even one of those fancy scopes that lights up a little red dot in approximately the right place. That said, I wouldn't be without my LRF binos, since I am not great at eyeballing it. Neither are some guides, I've discovered. And a little drop table inside the 'scope cap to remind me, because I don't do this every day.
When really good monometal things in target calibres like .338 Lapua Magnum emerged, range safety distances had to be re-considered, HME rules introduced etc. I recollect that there was an unfortunate incident at Bisley when one was found stuck in a school windowsill, miles away, but I don't recall the exact details.
They also have to be manufacturable at reasonable cost, have good terminal ballistics over their useful ranges of distance and velocity, possibly be lead-free, have an ogive profile that is not fussy about seating depth, actually I think it's a lot more complicated than designing a simple target bullet, and we are blessed to have so many choices these days.
BC, be it 1,2,3,4,5 etc is actually a useful approximation. Perhaps with modern computational fluid dynamics you could get a better grasp.
Ballistic coefficient - Wikipedia
Then there are genuine things to consider, such as the direction of your rifling twist, the more common right-hand twist will cause the bullet to lift significantly in wind coming from the right, or drop if it is from the left, for example.
Humidity, air pressure/altitude, temperature. Humidity is a big one, I've seen people having to make major 'scope corrections as the day warmed up and became muggy
Then coriolis. If you are shooting say .50 BMG, a relatively slow round, at 2km it even makes a difference shooting on the North-South axis laterally, if East-West in vertical. The Earth is spinning at about 1000 mph, 1470 fps, at the equator, zero at the poles. Very very simplistically put, not actually correct, when the bullet leaves the barrel, the Earth (and the target) revolves beneath it whilst it travels. It's real, and taken into account in advanced gunnery calculations.
But, hey ho, zero 1" high at 100 yards in the traditional manner, convince yourself that you can get three shots into 1", after a few attempts, stalk close, point and shoot and call it good enough.
Or carry a laser rangefinder, a Kestrel, and mobile phone app. Great on the range, not so much in the field. Even one of those fancy scopes that lights up a little red dot in approximately the right place. That said, I wouldn't be without my LRF binos, since I am not great at eyeballing it. Neither are some guides, I've discovered. And a little drop table inside the 'scope cap to remind me, because I don't do this every day.
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