no weapon < club < blade < pistol < rifle < heavy ordnance

Per the request today by Right Minded in Sunday School, here is an extrapolation of a statement I made a few days ago.


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First, a few thoughts on non-projectile weapons:

No weapon

Self explanatory. I suggest martial arts. Brazilian Jiu-Jitsu, Wrestling, Boxing, Muay Thai are the best choices. There are other good choices for self defense, but that is beyond the scope of this request.

Club
Small stick < large stick < broom < baseball bat < Buford Pusser style 2x4

Blade
Boxcutter < small knife < Bowie knife < bayonet < sword < English Broadsword < Scottish Claymore < Japanese Katana

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Now to the meat & potatoes of what Right Minded wanted:

In general:  Rimfire < Handguns < Shotguns < Rifles

Rimfire

22LR
- .22's come in pistol and rifle varieties.
- Adequate for hunting up to coyote-sized game at less than 100 yards.
- While people have been killed by .22's they are not well suited for self defense.
- However, a .22 beats a knife in a fight, if for no other reason, than the psychological.

Others
- .22 Short, .22 Long, .22 Magnum, .17 HMR are the most common.
- .22 Magnum is marginally considered for self defense, the others are similar to .22 LR.

HANDGUN

Handguns - Revolvers and Semiautomatic Pistols - come in several varieties. I'll not go into makes, as that is another entire blog post (or 12) in itself.

"Mouseguns"
- Too small for realistic self defense. Marginally better than .22 LR, if at all.
- Often, these calibers are prone to jamming and other malfunctions.
- .25 ACP < .32 ACP < .380

General Pistol Calibers
- Wide use as military, police, and CCW sidearms.
- Modern defensive ammo makes these calibers very similar in penetration results.
- Any of the below is perfectly acceptable for self defense.
- Heavier bullets generally preferred.
- 9mm < .357 SIG < .40 S&W < .45 GAP < .45 ACP < 10mm

Revolvers
- Widespread use in past for police.
- Very reliable.
- any of the below is perfectly acceptable for self defense.
- Heavier bullets generally preferred.
- .38 Special < .357 magnum < .44 Magnum
- .45 LC is also perfectly acceptable.

"Super-Revolvers"
- Since the .44 Magnum can provide near carbine performance, other revolver calibers were produced to increase on this performance.
- Generally not a good choice for a novice.
- Excellent for self defense.
- Calibers include: 50 AE - 500 S&W - .454 Casul - .460 S&W Magnum

SHOTGUNS

Shotguns are excellent self defense choices. A shotgun has far more power than a typical handgun. There are several schools of thought for self-defense loads, but commonly accepted logic holds that buckshot and slugs are superior choices for self defense. Avoid birdshot for self defense.

- .410 shotguns are underpowered and generally not good for self defense. Again, like .22's - there have been cases of people being killed by .410's - but this is the exception.
- 28-gauge and 16-gauge are perfectly fine, but are hard to find ammo for.
- 20-gauge is fine. In fact, 20-gauge with #4 buckshot is a great combination for self defense. Slugs are good, too.
- 12-gauge is the standard. Typically 00-buckshot is ideal, along with most slug choices.
- 10-gauge is the most powerful shotgun, but try finding ammo for it.
- .410 < 28-gauge < 20-gauge < 16-gauge < 12-gauge < 10-gauge

RIFLES

Rifles are the best choice of a firearm for self defense. If this were not the case, then military units the world over would not select Rifles as the primary weapon of their soldiers. However, not all rifles are in military use, so I will divide rifles up as such: military use and non military use.

NON-MILITARY RIFLES

Non-military - Varmint Rifles
- Good for hunting small game
- Some are good selections for game as large as deer.
- Common choices: .204 Ruger - .22 Hornet - .222 Rem - .220 Swift - .22-250

Non-military - Midsize cartridges
- Good for small game.
- Most are popular as deer calibers.
- Some (.270, 7mm's) are good for game up to Elk, Moose, and Bear.
- Common choices: .243 - .25-06 - .270 family - 7mm family

Non-military - .30 caliber cartridges
- Good for game deer-sized and larger.
- Common choices: .30-30 - .30-06 - .300 H&H Mag - .300 Win Mag

Non-military - large bore
- Good for large game
- Common choices: .35 Whelen - .375 Weatherby Magnum - .416 Rigby - .470 Nitro Express

Overview:
Non-military rifles are typically bolt action or lever action, with a very few semiautomatic choices. While good for self-defense, over-penetration will be a problem on all but the varmint calibers. Varmint calibers might not have enough power for self defense (.22-250 excluded).

One shot would likely end the fight, but if it didn't, the ability (or lack thereof) of getting off a second shot, coupled with the likelihood of over-penetration, make these rifles marginally less desirable than shotguns for home defense.

Also, I would say that non-military style varmint calibers rifles would not be as good as a properly loaded shotgun for home defense. 

Exception:
I would make an exception here for lever-action rifles in revolver calibers. Specifically, lever action rifles chambered in .357 magnum and .44 magnum are actually very well-suited for home defense. The only disadvantage is slower follow-up shots due to the lever action as opposed to a good semiautomatic. These rifles get better ballistics than the M1 Carbine, and have proven it by repeatedly taking deer out to 125 yards.

MILITARY RIFLES

Military Carbines
- Excellent choice for self defense, SHTF, alien attacks, or zombie infestations.
- Generally effective to 300 meters.
- Generally have larger capacity magazines.
- Generally use an intermediate cartridge.
- Common choices: .30 carbine, .223 / 5.56mm, 5.45mm, and 7.62x39
- Wildcat options: 6.5 Grendel and 6.8 SPC.
- Rifle types - in order of preference:

AR-15 (.223/5.56mm, 7.62x39, 6.8 SPC, 6.5 Grendel);
AK-platform (7.62x39 & 5.45mm)
M1 Carbine (.30 Carbine);
SKS (7.62x39) 

Military - Battle Rifles
- Excellent choice for self defense, actual combat, and anything else a military carbine might be used for.
- Effective to 800+ meters.
- Recoil is harsh compared to carbine rounds.

- Bolt-action calibers: .303 British - .30-06 - 8mm Mauser - 7.62 x 54R, 6.5mm Swedish, 7.5x55 mm Swiss.
- Semiautomatic calibers: .308 / 7.62x51 NATO - .30-06
- Battle Rifle preference, in order:
AR-10 (7.62x54)
M1A / M14 (7.62x54)

M1 Garand (.30-06)
Bolt Action (varying calibers)

Military - "Sniper" Rifles.
- Expensive!
- Massive Recoil
- Bolt action and semiautomatic are available.
- Effective past 1000 yards.
- Choices: .338 Lapua, .50 BMG

Exception:
The 5.56mm AR-15 Rifle, when outfitted with a 20" barrel as originally designed, is able to reach out to 500 meters with effective fire. It maintains moderate recoil, and weighs far less than a battle rifle. It is sort of an in-between with regards to the Military Carbine and the Battle Rifle - with some of the best characteristics of both.

Overview:
Since Battle Rifles will have over-penetration issues, They are secondary choices for home defense. However, they might move up to primary choices in SHTF, alien attacks, or zombie infestations.

Same goes for Military "Sniper" Rifles. A .50 BMG has been documented to be able to shoot through a concrete wall, a person, and a concrete back wall at over a mile away. In a home defense environment, the over-penetration would likely kill the intruder, the neighbor, the folks in the next subdivision, and possibly enter a house in the next county. Not good.

"Military Carbines" are the best overall choice for home defense. They can hold 30 or more rounds of ammo in a single magazine, and have a well-documented ability to put an attacker down in a fight. Carbines are relatively lightweight, easy to handle, and have only moderate recoil.
The AR platform is very customizable and has 1000's of accessories.
The AK platform is relatively inexpensive and very hardy.
The M1 Carbine is under-rated (by those that haven't shot one!).
The SKS is a no-nonsense rifleman's rifle... it's also the cheapest of the bunch.

Oh, and chicks dig the carbines - especially the M1 Carbines and AR-15's.