"It would be convenient to leave ballistics completely out of a discussion of whether a PCC or rifle caliber carbine is more effective! But shouldn't terminal effectiveness be one of the primary considerations when choosing something to stop a deadly threat? Especially in a home where the ability to conveniently carry it is N/A?"
1) Since a portion of the discussion hinges on whether PCC's offer
any advantages over a carbine (sounds like a strawman, but there are actually a good number of folks here/elsewhere who claim this), focusing on something other than that
one clear-cut facet of the choice seems totally valid. More valid than claiming nothing else matters so long as the 223 is so much more powerful, or that the very power differential itself doesn't carry with it significant costs/drawbacks
2) I disagree that terminal
ballistic effectiveness is a primary consideration, since any service pistol caliber is fully capable of immediately stopping a threat with an acceptably high rate of success. But even before you get to those kinds of worries, you have to consider personal preferences for various tactics/beliefs, with some folks opting for multiple accurate shots, others for very few devastating shots (certain wisdom underpinning both schools of thought, btw). The rapid double/triple-tapping folks would be wise to choose a 9mm carbine over a 223; there's simply no question your follow up shots will be faster with a less powerful round. But if you think you'll only have time for one or two shots, the rifle class rounds are more desirable, since there's a slightly greater chance an off-optimum hit will still incapacitate the threat rapidly enough.
3) Comfort of carry in a home is hardly non-applicable. You can carry a pistol with you everywhere in your home, an AR or PCC is far more cumbersome (with the latter being capable of being only slightly less cumbersome). If it ain't on you when the action starts, it doesn't matter.
"The reason ballistics aren't a deal breaker in practical HD is the same reason it isn't on the street for civilians...statistically, criminals will disengage from an armed threat more often than not."
I would also argue that hits from anything 9mm and above have proven to reliably stop threats quickly enough, which is why they stay in use for exactly that job. Guns of all calibers do carry a very real deterrent factor for a threat when they are making that split-second fight/flight calculation in their lizard-brains; but it's good to be able to make good on your end of the bet if their math is wrong. 380 and above has shown capable of that, 9mm and above has shown to reliably be capable of that.
"The FBI advises to plan on having to fight for 15 more seconds after shooting someone through the heart with a handgun."
Do they advise for rifles? I'm curious if it's any different (15 seconds isn't all that long to keep a
very close eye on the threat, and you should really be continuing to fire on them if possible until they present a threat no longer, 15 seconds be damned. Regardless the bullet you're shooting)
"If you have a PCC and can use it well, it will be good for HD, but take advantage of its superior shootability to precisely place your shots (heart or mid-brain) to make up for the lower terminal effectiveness."
So you
wouldn't need to hit these same areas with a rifle round to reliably stop a threat? I had no idea a 223 to the gut or shoulder (or pinkie toe, to use the cliché) would drop someone without question. Sure seems like you need to hit the upper chest or heat, regardless, with the AR's results being far more dramatic if successful. That extra "drama" can make all the difference in a borderline shot, but a hit to the head/heart means the shooter has done about 95% of what can be done, already (again, regardless of caliber). Is the additional damage done to the area you had to hit in the first place really an advantage over being able to make follow up hits faster and more accurately? I think it's just a philosophical/experiential question more than anything that can be hashed out definitively online. Which is why I take exception to the notion that ARs be universally recommended over PCCs reflexively. We don't even do that with shotguns, which are proven time and again to be terribly risky defense items (in several ways; misperceptions about needing to aim & difficulty of doing so with just a bead in the dark, very slow follow up shots & severe recoil, and the worst over penetration characteristics of any option out there (and the fact your projectiles' wound paths are narrow/linear, even if there are likely multiple hits)
"First, a pistol caliber carbine may not be quieter than a short barrel AR."
I wanna see some numbers from a legit source before I'll buy that. Sorry, but unlike the "223 BTHP rounds not penetrating as deep as buckshot" un-intuition, I don't see any physics-based reason for how a higher-pressure cartridge with far more powder/power could possibly be quieter when uncorked than a lesser alternative with the same length barrel. A PCC could
sound louder to human ears if it operates in a different vocal register (pitch), but there is simply more energy being dissipated in the form of sound by a 223 than a 9mm/45acp. Again, unless I'm missing something backed by solid physics.
"There's obviously a lot of rhetoric here by folks who have never fired a PCC, indoors or out. The difference between the same cartridge fired in a rifle versus a pistol is HUGE."
Until I'd fired a 16" barreled Uzi, I wouldn't have thought it so stark, myself. But the gun practically sounded suppressed with only a set of earplugs in. ARs are painfully loud through my
face (independent of muffs/plugs) unless I am squarely behind the barrel or there is no muzzle device attached. Much worse if there are any hard/flat surfaces nearby to reflect sound (which is why I don't buy the "linear comp makes it quieter" argument; maybe at the range with the bullet trap 25yds away, but not in your bedroom)
"Funny how in a hunting discussion, it is accepted that a 250gr .45 at 900fps will fully penetrate any deer that walks and kill it deader than fried chicken but when shooting people you need a rifle. Further proof that perception is everything."
Funny how a lot of folks claim hunters have no valid opinion on defense issues, too. Especially in light of the fact that hunters have as much incentive to rapidly drop their target (so it can't run/get lost, rather than so it can't keep being a threat), and also have the benefit of generally having more time to make their shot (and since it's their only shot, this generally means bringing "overkill" to bear on their target with exceedingly powerful rounds). If a hunter desiring a DRT deer, with plenty of time to line up a shot, with the tendency to use more powerful rounds than necessary in order to guarantee a rapid kill,
still finds 40cal/45acp/10mm/357mag to be sufficiently effective on large-ish animal targets (smaller but tougher than us)...it stands to reason they'd do alright in the home defense capacity against garden-variety unarmed foes.
"The PCC was:
Quieter.
Had less flash.
Quicker between shots. (about 15%)
Quicker between targets. (about 10%)
More accurate on second and third shots. Well it would be better to say easier to be accurate with on follow up shots."
So pretty much what the physics of shooting a less powerful round would indicate. That leaves the remaining "figgering" to be whether or not additional power on that first shot meets or exceeds the effectiveness of delivering a second shot. Anyone here willing to make a guess at how much more effective a 223 would be at disabling than a 9mm given a torso/head shot? Is it more than double the 9mm?
"There are the obvious ballistic differences between the two, but if you think 9mm is sufficient ballistically then the PCC makes sense. Or to look at it another way: Would you rather tilt your shootability equation towards speed and accuracy, or energy/round? In reality either are probably good choices, and with training will serve you well."
At last, some even-headed advice
. I, personally, see rifles as too far towards the "all eggs in one basket" approach, wherein a massive barrage is unleashed at a target. Since worst-case dictates that multiple hits are required to stop an opponent, you are now at a disadvantage than if you had a faster follow up shot. If the unsuccessful first hit is assumed to be the situation regardless the weapon chosen (and no one assumes their first hit will be the only one needed, after all), you will need at least a second, and as fast as possible. After two or more successful hits of something as powerful as 9mm or higher, the likelihood of needing additional becomes astronomically small, and simply having magazine reserve fulfills the obligation of preparedness, there.
I know "planning" a shootout is pointless/counter productive, but planning to hit the target solidly, then having to hit them solidly at least once more when the first is unsuccessful, seems pretty universal to all possible altercations.
TCB