Well you do see 90grain .224 bullets but for instance in the 223/556 world a 90gr. bullet will not feed from a magazine so few people would purchase loaded 223/556 ammo in 90gr. weight 77gr. is about the most you can reliably gurantee. Now if you wanted to single load and you reload not a problem!
In the 1980's I all but begged manufactures to increase twist rate on 243Win and 25-06Rem chambered rifles and for bullet and ammo makers to load heavier bullets especialy for the 25-06. Manufactures of rifles and ammo are very stupid and risk avoiding people! They are about as inovative and forward lookng as a blind squirel! Unless I ammistakenand I might be no major firearm mass producer makes a 243Win rifle with the same twist they offer in 6CM and if they finaly do they still deserve a swift kick in the Jimmie's for making us all wait 30+ years for what has been common since. I hate SAAMI and 99% of firearm manufacturs because they give us antiquated and out of date chamber designs, tolerances, clearances, and twist rates because they are both stupid and risk adverse! It does not help that most people that purchase rifles are morons and have very low standards and expectations from the manufactures of said firearms. The 25-06 could have been a legend by now with faster twist rates and heavier bullets.
Shortly after David Tubbs won Silhouttee Nationals with a 243Win I campaigned one. There where many times I could have won with an off the shelf rifle decades ago if I could have purchased a rifle with a fast enough twist rate. Instead I had to purchase custom barrels and to achieve what I wanted. Not because I needed a custom rifle to win but because I needed a custom rifle to fire the bullets I needed to set myself up to win! Last I checked this is still an issue!
Now in the instance of the industry actualy making the bullets you want or need it is always a matter of never being able to buy off the rack and shoot said bullets. THe other is if you do not reload you can not shoot the bullets you want to shoot often!
Take the 8mm Mauser unless you reload for many decades all you could find at the store was Remington CorLokt in 150gr. soft point loaded to 30-30 velocities! Finding a decent 8mm bullet not intended for the 8mm Remington Magnum heavier than 150gr. and quality brass to load to WWII standards or better was diffacult!
Same thing with 45-70 ammo for decades if you could get it it was loaded to be safe in great, great, great grandpa's Springfield Conversion of a Springfield M1861 Musket as used during the Civil War and converted into a Trap-Door Springfield 45-70. Now I am only 51 years old but I can not imagine that the bulk of people shooting 45-70 ammo are shooting it through a Springfield M1861 Musket Trap Door Conversion! To assume that is the case and load according is so ignorant as to make the Peter Principal make perfect sense. We do not make motor oil today with the assumption it will be used in a Ford Model T or make diesel engines today assuming they will be run on peanut or cotton seed oil or burbon! We do not build 100 ton 20HP engines today and do not spec things accordingly because technology has moved on. At some point their is litigation proof and there is idocracy! Imagine someone assuming planes are still built from dope coated fabric and wood and hampering the entire industry because planes where once built from wood and fabric! You make exceptions where they must be made and you place some level of blame on the consumer you do not hold back all of society or industry because of the past.
Cessna stoped making airplanes for a few decades becasue of the liability laws and litigation in the USA! The entire industry and those wanting a product where frced to suffer because of liability laws and litagation. Cessna lost their rear end because a Doctor flew his plane into the side of a mountain and his wife sued and because no place int he operators manual and no place int he aircraft did it say "Do not fly this aircraft into the Earth at a 45° angle she won a huge amount of money. Shortly after that Cessna stopped making light aviation aircraft for decades.
Some of what we suffer is from Ivy League MBA's, Lawyers, and from midwits in industry that are happy to turn out what they have always turned out!
I am 51 now and the average life expectancy of a white cis-gendered adult male int he USA is about 75 years old. I doubt anything much will improve in the next 24 years in the USA. We reward incompentence too much and will not do what needs doing to move society forward in a meaningful way! I predict the lowest common denominator will prevail in the future.
In 1980 adult literacy in the USA was around 99.5% aproximately and today in 2023/2024 it is about 79%! Let that sink in! In 1985/86 in the 6th grade I could work a lathe, end mill, stick weld, spot weld, use a metal break, drill press, band saw and had to demonstrate those in class to pass industrial arts class. I was expected to do Alegbra 1, write poetry, diagram sentences, comprehend Animal Farm and Russian Hisotry in English Class, and under stand US History up to 1865 in 6th grade in History Class. Still had to show up for Art Class, Home Economics and Band as well as run 2 miles at the begining of PE class every day before we could do the fun stuff! In 5th grade we had to be able to count back change and ballance a check book! By my Fressman year I was doing mechanical drawing and aritecture and aprenticing to be a mechanic while still doing A&P Chemistry, A&P Biology, Anatomy and Physiology, Russian and German. My point is that part of the problem is lowering of standard and education and a degenration of societal norms and expectations! All of these things are endemic of the failure of society on a global scale. While total knowledge has increased and technology has increased the understand of these things from society in general has declined. The consumer is more removed than ever from the relavant technology of the age as well as an understanding of the techology, philosphy, theology and ideologies that have lead us from our ancient begining to where we are today. An 8th grade education from a really good school system from the 1960's is about the same today as what you would expect from someone with 2-4 year degree from a major university today. The key difference though is that you would expect that 8th grader fromt he 1960's to be able to think through a problem they had never encountered and solve it because they where taught how to think not what to think! That same expectation is not the standard today because ideology is more important than actualy learning how to think and how to apply what you already know to solve an unknown! When we landed men onthe moon there where very few men or women that had more than a 2 year college degree working at NASA!