This is just a train of thought that I had while doing research for a match AR15 barrel for 0-600 yard paper punching. Interested to hear what you guys think on the subject,
I really don't want anyone to get hung up on "best" since best is subjective and often confused with "perfect". Best for me is a composite of solid ballistics and range capability, accuracy, cost, ease of finding parts and components. Surprisingly while trying to determine which of the popular cartridges available on the AR15 platform was most suited to a match accuracy 18-20" SPR style rifle, the oft called puny 223/5.56 still seems to be the best fit.
I had figured that the rise in popularity of snazzy new wildcats like 6.5 grendel, 6.8spc, 300blk, 7.62x40wt, etc would have rendered 223 obsolete by now in the 600yard range. The issue is that for every edge these beefier cartridges have over .223 they seem to have a pile of problems. I got my ballistics info by using various reloading manuals in conjunction with JBM.
6.5 grendel:
Pro: Much higher BC's and above transonic speeds out to 1k, more energy than .223
Con: Prohibitive prices on barrels (500$+), components are as expensive to shoot as .308, feeding issues.
6.8 SPC
Pro: Heavier bullets with more energy at range (barely), some subsonic capability
Con: Transonic at a shorter range than .223, poor selection of bullets, (the light bullets required to get out to 600 yards are blown around more than 223)
300 blk
Pro: Very spiffy capabilities with subsonics, supersonic to 600 yards with the right loads, cheap brass and bullets.
Cons: The light .308 bullets needed for longer range get wrecked by wind, transonic at 500-550yards
7.62x40 WT
Pro: You tell me, only Wilson seems to know why we should buy this cartridge. Cheap match barrels is a plus.
Con: No load data
Finally .223/5.56
Pro: Cheap components, barrels, and factory ammo. High velocity resulting in 600 yard energy comparable to anything but 6.5 grendel, supersonic at 1k (75gr hpbt at 2800fps), solid reliability, excellent accuracy, no need for new bolt/magazine.
Cons: Low BC bullets get kicked around by the wind.
A lot of this probably seems obvious to you guys, but I went into my search for a new barrel expecting .223 to be severely outclassed by the new cartridges available. Unfortunately, the cartridges that should be competitive are either too expensive, or simply not long range viable. Maybe I'm just spoiled by the ease with which 308 tackles 600 yards, but It seems like there should be more options in the Ar15 platform that can handle it.
I really don't want anyone to get hung up on "best" since best is subjective and often confused with "perfect". Best for me is a composite of solid ballistics and range capability, accuracy, cost, ease of finding parts and components. Surprisingly while trying to determine which of the popular cartridges available on the AR15 platform was most suited to a match accuracy 18-20" SPR style rifle, the oft called puny 223/5.56 still seems to be the best fit.
I had figured that the rise in popularity of snazzy new wildcats like 6.5 grendel, 6.8spc, 300blk, 7.62x40wt, etc would have rendered 223 obsolete by now in the 600yard range. The issue is that for every edge these beefier cartridges have over .223 they seem to have a pile of problems. I got my ballistics info by using various reloading manuals in conjunction with JBM.
6.5 grendel:
Pro: Much higher BC's and above transonic speeds out to 1k, more energy than .223
Con: Prohibitive prices on barrels (500$+), components are as expensive to shoot as .308, feeding issues.
6.8 SPC
Pro: Heavier bullets with more energy at range (barely), some subsonic capability
Con: Transonic at a shorter range than .223, poor selection of bullets, (the light bullets required to get out to 600 yards are blown around more than 223)
300 blk
Pro: Very spiffy capabilities with subsonics, supersonic to 600 yards with the right loads, cheap brass and bullets.
Cons: The light .308 bullets needed for longer range get wrecked by wind, transonic at 500-550yards
7.62x40 WT
Pro: You tell me, only Wilson seems to know why we should buy this cartridge. Cheap match barrels is a plus.
Con: No load data
Finally .223/5.56
Pro: Cheap components, barrels, and factory ammo. High velocity resulting in 600 yard energy comparable to anything but 6.5 grendel, supersonic at 1k (75gr hpbt at 2800fps), solid reliability, excellent accuracy, no need for new bolt/magazine.
Cons: Low BC bullets get kicked around by the wind.
A lot of this probably seems obvious to you guys, but I went into my search for a new barrel expecting .223 to be severely outclassed by the new cartridges available. Unfortunately, the cartridges that should be competitive are either too expensive, or simply not long range viable. Maybe I'm just spoiled by the ease with which 308 tackles 600 yards, but It seems like there should be more options in the Ar15 platform that can handle it.
