https://www.shootingtimes.com/editorial/65-prc-vs-other-65mm-cartridges/372107 . (please note, article dated 07.23.2022 by john barsness. a big buddy of hornady, btw.)
accounting for seating depth of similar bullets, the internal capacity of the hornaday 6.5mm prc (all the rage in long range shooting), the remington 6.5mm magnum and the wildcat 6.5mm/06 (the former much despised in some circles, and the latter too easy to make to consider) is just about identical.
it is roughly 62 grains of water (water being about the same weight by volume as most smokeless powders.) (who knew?)
now, the 6.5mm's as produced by hornady are currently "just the thing" for long range shooting and some hunting applications. the 6.5mm remington magnum is just about moribund. and, the 6.6mm/06 just lacks cachet, being far too common for people who want just the latest thing.
yet, if there is a dime's worth of difference in the three cartridges, loaded with similar care and attention and in quality barrels and actions, i would like to know about it. loaded with the same charges of powder, in barrels the same length measured from bullet tip to muzzle, and in rifles with barrels from the same makers with the same rate of twist they are going to shoot just about the same. having the same case volumes, loaded with the same charge weights, they are gonna generate very similar pressures, and velocity ..... it cannot be otherwise.
yet, the hornady offering is selling like hotcakes, and you probably couldn't give away the remington chambered rifle if you had it in stock.
why?
i am old. old is 74 years of age w/ four bypasses, 6 cardiac stents, and 3 active aneurysms of the aota, one at the root of the aorta (not a good place, trust me!!) and two on the artery feeding the spleen. if i ever had any sexual prowess, it has long ago vanished. yet i would dearly love to see amanda tapping and claudia black without any clothes on. they are very different, in their own little ways (i suppose), yet they are both beautiful women.
how does one (with any conceivable different sets of proclivities) chose between them. such would be a very very very difficult task.
yet, it is precisely the set of choices as between the 6.5mm prc, the 6.5mm remington mag and the 6mm/06 wildcat. there are simply distinctions without differences.
the whole thing is really obtuse between the hornady and the remington factory cartridges. they are very close to the identical length, and case dimension, save the remington has the surplusage of the h & h magnum belt. both cases should properly be headspaced between the face of the cartridge rim, and the datum line on the case shoulder .... as a practicable matter, i doubt that the distance varies between the two cartridges one whit. (e.g., not very damned much!!)
chambered to the datum lines with equal care, bullets seated to the same depth, cartridges the same overall length, and chambered in equal quality rifles by competent smiths, i can see little if any difference.
yet, one is a raging success, and one is an also ran.
someone explain the difference to me, in rational terms.***
john jay @ 08.13.2022
*** well, there is one difference. it is gun writer's, and the licking of the arses of the same. if i had the choice of buying a 6.5mm prc new off the shelf, and the purchase of a 6.5mm rem mag "used" in very good condition, i would buy the old remington. no deer would be able to tell the difference. convince me otherwise.
post script. as a matter of fact, if you were to machine the belt from the 6.5mm rem mag, and reduce that part of the case down to the basic diameter of the case just in front of the belt, you would have a very very hard time distinguishing the 6.5mm rem mag from the 6.5mm hornady prc.
this is no accident.
the barsness article describes how the "designer" of the 6.5mm prc basically turned to the ruger compact cartridges for inspiration, deciding that the rcm's had just about the case capacity to give him the ballistic performance he was after .... just at 62 grains of water w/ a seated bullet.
the same capacity as the 6.5mm rem mag. remember.
now, keeping that in mind, understand that the ruger compact case (rcm) was basically designed to fit a bolt fact in a rifle, of a h & h pattern magnum case with the (offending belt and "excess diameter" rim removed, to have a cartridge with a case rim the same size as the h & h case body. this figure is right at .512 to .513". oops, color my face red. i got that exactly ass backwards. the ruger case has a rim of .532" diameter, but with no belt, as the case body is the same diameter as the rim, that being .532".
check the hornady prc case dimensional schematics. you do it.
so, again, it is entirely no "accident," that the hornady 6.5mm prc is basically, (if not in actual dimensional fact), & fundamentally a twin of the 6.5mm remington magnum cartridge with the h & h pattern belt and rim removed. made absent. shaved off, as it were.
and, it would be "no accident" whatever, were a little gentle massaging of cartridge, rifle, fitting, and head spacing, for the 6.5mm rem mag to provide just about identical ballistics and accuracy to the hornday 6.5mm prc. there just would not be any mystery to it, at all.
find a "gun writer" who will say it. i double dog dare you. end post script.