Longdayjake has the right perspective on long bullets for their caliber. Here's the best examples I know of.
The US Army International Teams switched from 6.5mm European rounds in their 300 meter free rifles in 1958 after getting Sierra Bullets to make a 30 caliber 168-gr. HP match bullet for the .308 Win. case. Until then, they were all FMJBT ones. It's superior accuracy over all the others was later used in their 200, 190 and 180 grain HPMK bullets that became the standard for 30 caliber winners and record setters to use. Hollow pointed bullet jackets had more uniform heel diameters and wall thickness and therefore enabled better balance of the bullets. That enabled Sierra to finally get 10-shot test groups in production runs down to well under 2/10ths MOA/inch at 100 yards; tiny ones around 1/10 were often shot.
In 1969, Sierra Bullets started making 26 caliber 140-gr. HPMK match bullets. As I was shooting a .264 Win Mag for my 1000-yard prone rifle then, Sierra gave me two boxes of their prototypes to test. I did so and shot most promising initial test loads into two 20-shot groups at 1000 yards were that many inches in size; two MOA. No good for competition at all. I was using Norma's 139-gr. FMJBT match bullets at the time getting sub MOA accuracy at 1K yards. Gave the remaining bullets back to Sierra saying they didn't shoot so well. Sierra replied with the same comment. Their 30 caliber 190- and 200-gr. bullets from good lots sold at matches in plain brown boxes of 1000 each tested into 5 or 6 inches all day long at 1000 yards.
A year later, Sierra made some 28 caliber 168-gr. HPMK's to see how they would do. Using a partial roll of jacket material that was left over from making a lot of 30 caliber 190's that shot about 1/10th MOA in their test range, they made several hundred bullets to test. Their ballistic tech's own 1000-yard match rifle was rebarreled with a Hart 7mm Rem Mag one, Initial tests showed it very promising with a charge of IMR4831. He loaned that rifle to a good USN friend of both of us to shoot in the 1000-yard scope match at the Nationals. He set a new record; 100-32V on the old C target in 1970. Those bullets shot under 1 MOA at 1000 as judged by my friend shooting them. V ring is 20 inches. Another USMC friend broke that record later in 1972 shooting a .30-.338 with 190's with a 100-42V.
Sierra's regular production lots of those 26 and 28 caliber long heavy bullets didn't have the quality of jacket material good enough for the coin, cup, draw, core and shape dies to make uniform jacket thickness for long bullets. They switched from Olin to some German company making jacket material to better specs. But it wasn't until the late 1980's before 28 caliber long jackets for heavy bullets could be mass produced to tight specs and the 7-08 was popular for XTC matches. Lots of folks flocked to the 7 Rem Mag for their long range match rifle but bullet lot consistency varied quite a bit; the 30 caliber mags ruled the roost.
26 caliber ones had to wait until the 1990's before 140-gr. ones could be made to equal what the 30 caliber 200 and 220 ones had for jacket thickness uniformity. That's when the 6.5x.308 (basis for the .260 Rem) 6.5x.284 began to take home all the marbles.
24 and 22 caliber match bullets had the same thing happen. David Tubb told me he could hardly wait until Sierra made really good, long heavy 6mm bullets so he could shoot the .243 Win as his XTC rifle. He then designed his own 6XC round based on a shortened .250 Savage case. The 6mm Dasher has proved very accurate at 1000 yards; it never would have done that back in the 80's with the best jacket material made then.
Making bullet jackets is akin to making cartridge cases. Longer ones for their diameter are hard to make with uniform wall thickness. Accurate cartridge cases are shorter for their diameter than the others.
