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Post by bubba on Sept 9, 2006 8:23:26 GMT -5
I am confused, I know it doesnt take much.......
How does a same weight bullet in 243 caliber have a better ballistic coefficient than the same weight bullet in a 22caliber bullet? I dont get it?
Can someone explain that to me?
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Post by minst7877 on Sept 9, 2006 22:36:50 GMT -5
Weight to length ratio
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Post by bubba on Sept 10, 2006 16:04:09 GMT -5
okay, if they are the same weight, isnt the 22 bullet longer? Thus it should have a better BC right?
It dont work that way tho !
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Post by wilmsmeyer on Sept 10, 2006 18:10:44 GMT -5
Bubba,
According to my Nosler Reloading guide (#4) you are correct.
55 grain NBT .224 = BC of .267
55 grain NBT .243 = BC of .276
I'm not sure of the reason and my brain makes me ask the same questions that you have. Hope a real genius will enlighten us.
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Post by minst7877 on Sept 10, 2006 18:56:27 GMT -5
okay, if they are the same weight, isnt the 22 bullet longer? Thus it should have a better BC right? It dont work that way tho ! But it does change the center of gravity on the bullet thereby possibly changing the way it stabilizes therefor the coefficient. |
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Post by bubba on Sept 10, 2006 19:03:29 GMT -5
DC, NO WAY, BC is a ratio of frontal area divided by something, so CG has nuttin to do with it?
put it this way, do you think that a 100gr 243 bullet has a higher or lower BC compared to a 100gr
50 cal bullet? I think that we all have the answer to that one, but that is just to prove the point.....
I am still confused ! it dont take much these days !
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Post by bubba on Sept 10, 2006 19:54:46 GMT -5
sectional density is the other variable, vs frontal area........... ug, it still doesnt add up?  |
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Post by whyohe on Sept 24, 2006 12:00:28 GMT -5
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Post by Rifleman on Sept 28, 2006 11:05:10 GMT -5
Bubba, BC's are not static they are dynamic and change with velocity. I would assume the .22 bullet's BC was calculated at a higher muzzle velocity then the .243's but I really don't know for sure. Good rule of thumb is to take all factory BC's with a grain of salt. Not the scientific answer you are looking for, but maybe a clue in the right direction, at least now you are not totally clueless!  |
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Post by bubba on Sept 28, 2006 13:34:57 GMT -5
Bubba, BC's are not static they are dynamic and change with velocity. I would assume the .22 bullet's BC was calculated at a higher muzzle velocity then the .243's but I really don't know for sure. Good rule of thumb is to take all factory BC's with a grain of salt. Not the scientific answer you are looking for, but maybe a clue in the right direction, at least now you are not totally clueless! I wouldnt bet the farm on the tobally clueless..........  |
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Post by Rifleman on Sept 29, 2006 5:31:01 GMT -5
your right I wouldn't.
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Post by mistered on Apr 21, 2007 23:43:18 GMT -5
I am confused, I know it doesnt take much....... How does a same weight bullet in 243 caliber have a better ballistic coefficient than the same weight bullet in a 22caliber bullet? I dont get it? Can someone explain that to me? I think I may know the reason for this apparent paradox. There is an ever so slight trade-off between the obvious length vs. diameter advantage and the amount of surface area that contacts the drag producing air. So in terms of identical weights contained in the bullet with the least amount of surface exposed to the air drag the slightly fatter and slightly shorter .243 is superior. .223 bullets compared to .243 bullets are an excellent example of this trade-off, because of their slight differences in diameter. More pronounced differences in diameters would cancel out any drag advantage as length vs. weight becomes more of an advantage. To make it a bit more understandable one needs to remember that forces increase at varying exponential rates. -Ed |
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Post by chuck41 on Sept 21, 2007 16:35:11 GMT -5
Bubba is Right. It doesn't make sense.
I suspect it is an error from the dudes that measured them.
Data from Midway's online catalog
Berger Match .223 60gr HP Match SD .171 BC .276
Berger Match .243 60gr HP Match SD .145 BC .241
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Post by wilmsmeyer on Sept 21, 2007 19:02:10 GMT -5
chuck41,
Looks like the Midway figures make sense.
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