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One of our eccentric and very knowledgeable members posted a comment that I find worthy of more discussion. "Think bullets before headstamps!" Is it simply demand for higher BC projectiles in certain calibers or is there something inherent about any given caliber that determines higher BC construction? I suppose if I was looking for competitive level accuracy, I might think bullets before headstamps. Who am I kidding, he's got me thinking bullets! 
WAR EAGLE!
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Campfire Kahuna
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Campfire Kahuna
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As for your question about demand vs. inherently higher BC, the answer is both.
Certain calibers have always included some very high BC bullets, not because of anything inherent to the caliber but because certain bore diameters were matched with very heavy bullets during the early days of centerfire, smokeless cartridge development. The best examples are 6.5 and 7mm.
Several old 6.5mm and the most popular 7mm military rounds used very heavy-for-caliber roundnosed bullets. Examples are the 6.5x55 with a 156-grain and the 7x57 with a 173-grain. Because of the long bullets, rifles for both rounds were given twists of 1-8 to 1-9.
Consequently, when spitzers came along the 6.5x55 and 7x57 could stabilize very high-BC bullets, thanks to their faster rates of twist over other early centerfire rounds such as the .257 Roberts and .270 Winchester, which used lighter-for-caliber bullets that stabilized in 1-10 twists. After that all 6.5 and 7mm rifles received faster twists than most other calibers, the reason both became popular as long-range calibers.
Fast-forward to the present, and we find the demand for high-BC bullest extending to all calibers--including some bullets that are too long to stabilize in the standard twists of some calibers. This also created a demand for faster-twist barrels, the reason we now see a lot of .224's and 6mm's with 1-9 or faster twists, and even some .25's and .270's.
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck
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OP
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So, it's simply up to the manufacturer to make such a bullet? At that point everything hinges on the platform?
Seems like .25 cal has been handed a raw deal. Am I still missing something?
WAR EAGLE!
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Think you got it.
.25s have always been seen as small game/deer rifles that don't require big bullets.
Islam is a terrorist organization.
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Mule Deer - excellent and helpful post.
NRA Member - Life, Benefactor, Patron
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As for your question about demand vs. inherently higher BC, the answer is both.
Certain calibers have always included some very high BC bullets, not because of anything inherent to the caliber but because certain bore diameters were matched with very heavy bullets during the early days of centerfire, smokeless cartridge development. The best examples are 6.5 and 7mm.
Several old 6.5mm and the most popular 7mm military rounds used very heavy-for-caliber roundnosed bullets. Examples are the 6.5x55 with a 156-grain and the 7x57 with a 173-grain. Because of the long bullets, rifles for both rounds were given twists of 1-8 to 1-9.
Consequently, when spitzers came along the 6.5x55 and 7x57 could stabilize very high-BC bullets, thanks to their faster rates of twist over other early centerfire rounds such as the .257 Roberts and .270 Winchester, which used lighter-for-caliber bullets that stabilized in 1-10 twists. After that all 6.5 and 7mm rifles received faster twists than most other calibers, the reason both became popular as long-range calibers.
Fast-forward to the present, and we find the demand for high-BC bullest extending to all calibers--including some bullets that are too long to stabilize in the standard twists of some calibers. This also created a demand for faster-twist barrels, the reason we now see a lot of .224's and 6mm's with 1-9 or faster twists, and even some .25's and .270's. +1 very well said
i dont need a ultra mag, i know how to shoot my 30-06
having that obama sticker on your car might as well say " Yes i'm stupid "
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Seems like .25 cal has Been handed a raw deal. Am I still missing something?
Match/target grade bullets in the quarter bore are the exception rather than the rule. Most .25 bullets are for hunting. Mike
Always talk to the old guys , they know stuff.
Jerry Miculek
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Campfire Kahuna
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Campfire Kahuna
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Exactly.
The 6.5's gained their reputation as super-accurate target rounds due to the traditional rifling twist, not any mysterious something about 6.5mm bullets. Until recently not many hunters were interested in shooting past 500 yards, where BC doesn't matter nearly as much.
In fact out to 500, muzzle velocity is just as important, if not more so, so there's no real external ballistic advantage in long, heavy bullets--though there can be when they hit game.
A lot of people "know" the 6.5's are somehow more accurate the .25's or .270's, but that simply isn't so. Accuracy is due to good bullets, fine barrels, etc. etc., not some magic bore diameter.
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck
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Pearls of wisdom again from MD. Dose that mean we may soon see the demise of the "inherently accurate cartridge" phrase that is so often trotted out?
Von Gruff.
Von Gruff.
Exodus 20:1-17
Acts 4:10-12
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"Dose that mean we may soon see the demise of the "inherently accurate cartridge" phrase that is so often trotted out?"
It should. Some few cartridges ARE 'inherently accurate' but differences are so small it requires a few hundred rifles to produce any statistically valid evidence. For any given rifle the greatest differences will lie with the rifle and the loads it's fed, not the shape of its chamber.
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Campfire 'Bwana
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Campfire 'Bwana
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Pearls of wisdom again from MD. Dose that mean we may soon see the demise of the "inherently accurate cartridge" phrase that is so often trotted out?
Von Gruff. Probably not. When does fact interfere with legend...?  That's a much needed phrase, used often to sandbag reasoning for why one's pet round is one's pet round...  Going there is not too unlike arguing religion...  DF
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Until recently not many hunters were interested in shooting past 500 yards, where BC doesn't matter nearly as much.
In fact out to 500, muzzle velocity is just as important I was going to post the same thing, but I didn't wear my flamesuit. I agree, BC doesn't really start to show its advantage until 500yds+. And I don't plan in shooting at big game that far. Wind and BC is another theory though...
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Here's how Homer Powley, often called the Father of American Ballistics, explained it to me in 1963. You can't get the same BC from a .224 diameter bullet as you can with a .308 190 grain bullet or a .264 142 grain bullet because the twist would be too tight. When you start going above .308 caliber with very long bullets you get issues of accuracy in the leaping blasting torquing rifle you have to shoot prone without sandbags or tripods.
Homer showed that the optimum caliber for high BC, the purpose of which was to buck the wind, was about 6.5mm. He constructed, with the help of Bob Hutton, then the technical editor of Guns and Ammo, a match rifle using the .300 Weatherby necked down to 6.5mm for 139 grain Lapua bullets. He gave it to a guy named Al Gutta to shoot in the 1000-yard national championships at Camp Perry. Hutton later wrote, in the Gun Digest, that the round was so hot that one of the bullets disintegrated in mid-air. What actually happened was that Gutta, who was not really a championship shooter, misfired on the wrong target, costing him any hope of placing high. I was there and saw it.
But Powley and Hutton were basically right, although today we know that there is no point in having too much velocity. Most 1000 yard matches today are won by a 6.5-.284.
Don't blame me. I voted for Trump.
Democrats would burn this country to the ground, if they could rule over the ashes.
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There is a lot to be said for having good brass as well. Good brass makes the difference between a match winner and an also ran, at least in the benchrest game.
If nobody makes good brass for a cartridge, it's going to be difficult for the cartridge to become established on the firing line.
Islam is a terrorist organization.
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Campfire 'Bwana
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Good brass makes a difference even for a casual range shooter like me.
I've been reloading a quantity of LC M118 match brass from LC81 ammo. This wasn't the best period for brass QC at Lake City. It's real easy to distinguish between cartridges assembled with brass sorted for neck uniformity and those that weren't. Both on the runout fixture and on target.
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Campfire Kahuna
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Campfire Kahuna
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I'm not going to go into the whole "inherent cartridges" thing again here, but did do an article on the subject a few years ago, interviewing several prominent people in the shooting biz. It appeared in either Rifle or Handloader (probably the latter) and also contains my personal view of the subject.
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck
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Campfire Ranger
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Gee, maybe we can finally put the ".308 is an inherently accurate cartrige" to bed.
If God wanted you to walk and carry things on your back, He would not have invented stirrups and pack saddles
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Gee, maybe we can finally put the ".308 is an inherently accurate cartrige" to bed. You might want to read MD's article.
Anybody who seriously concerns themselves with the adequacy of a Big 7mm for anything we hunt here short of brown bear, is a dufus. They are mostly making shidt up. Crunch! Nite-nite!
Stolen from an erudite CF member.
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Gee, maybe we can finally put the ".308 is an inherently accurate cartrige" to bed. You might want to read MD's article. Yes and reread it carefully as well as the post above. The fact is that some rounds ARE more inherantly accurate than others and it has been proven with nearly identical rifles firing hundreds of thousands of rounds. Bullet manufacturers tend to use certain chamberings to test bullets because they are more consistantly accurate. You can even search back on this forum for some of MD's comments on earlier threads. But it doesn't matter how big a mountain of statistical evidence you provide some people will never be convinced that the 308 is more inherantly accurate than the 30-06 as well as other chambering in other bore diameters that consistantly tend to be more accurate than other chamberings even will all else being equal. The facts are there for anyone willing to open mindedly research, some just won't and even when presented with the facts the still won't beleive them.......................dj
Remember this is all supposed to be for fun.......................
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