Caliber Selection

Caliber Selection

You may choose your caliber before or after choosing your gun. Many sidearms are available in a variety of calibers, and if you find a gun you like, then you'll need to decide what caliber is best for you.

There are a number of considerations when it comes to caliber choice:

1 Terminal performance (will it stop an attacker ?)

2 Firepower (do you sacrifice firepower if you select one caliber over another ?)

3 Availability (is this caliber widely available should you need to procure fresh supplies in a hurry ?)

4 Price (some calibers cost a lot more than others - and it's not size related)

Figure 1 - A Wide Variety of Calibers are Available

Left to right are: 22, 25, 32, 380, 9mm, 357 SIG, 38, 357, 40, 45, & 223 rifle ammo for comparison

Typical kinetic energies (KE) delivered by each of the above calibers are presented in Figure 2

Size can deceive, the 38 Special and 357 magnum rounds look large in comparison to the other handgun rounds. However, the 38 Special delivers about the same KE as the 380, and the 357 magnum's performance is matched by the physically smaller 357 SIG. The chunky 45's KE is also less than that delivered by the 357 SIG or 40, and only marginally higher than that of the much smaller 9mm.

It is often claimed that one or other of the above calibers is more accurate than the rest. In reality, all are capable of more than adequate accuracy when used in firearms of reasonable quality - accuracy is more a function of the gun than of the caliber.

Like most things in life, caliber selection is a compromise. Would you prefer to have a SIG 226 holding 16 rounds of 9mm, or a similarly sized SIG 220 with 8 rounds of 45 ? For many, the benefits of double firepower far outweigh any terminal ballistic benefit provided by the 45 ACP caliber.

Muzzle blast and noise may be an important consideration. The 357 magnum and 357 SIG rounds are especially loud. If you intend to use a small gun, then the more potent calibers may yield too much recoil to be comfortable - recoil forces are proportional to KE produced.

Table 1 summarizes the pros and cons of the calibers listed above.

Table 1

Caliber Pros & Cons

Caliber

Pros

Cons

22 long rifle rimfire

Small

Cheap

May kill an attacker - but not before he kills you !

25 ACP

Small ammo, & small guns

Expensive (2-3 times the cost of 9mm ammo)

May kill an attacker - but not before he kills you (less KE than a 22)

32 ACP

Size efficient

Reasonable ballistics (European loadings = 120+ ft.lbs KE from short barreled guns)

Puny performance if you use the US loadings (60 - 80 ft.lb KE)

Not a good attack terminator

Relatively expensive

Not available everywhere

380 ACP

Starting to get to reasonable diameter

Widely available

Not size efficient (only 30-50% more KE than best 32 in most cases)

Marginal attack terminator

Relatively expensive

9mm Parabellum

(9mm Luger)

Ballistically efficient

Cheap

NATO caliber (common)

Needs relatively expensive hollow point ammunition to avoid over-penetration (& ricochet) and produce good attack stopping performance

357 SIG

Good attack stopping performance

Adopted by several State & Federal LE agencies (should become more popular - & cheaper)

Noisy

Not available everywhere

Expensive (but getting cheaper)

38 S&W Special

Widely available

Cheap

Marginal attack stopping performance - even in +P loadings.

Large case size for performance delivered.

357 S&W Magnum

Widely available

Reasonably priced practice ammo

Good attack stopping ability - but needs hollow pint bullets (more expensive)

Large case size for performance delivered.

Recoil may be too much for some people - especially in smaller revolvers.

Noisy

40 S&W

Good attack stopping ability - even cheap FMJ varients

Widely available

Reasonably priced

No real disadvantages, but recoil may be too much for some in smaller guns

45 ACP

Good attack stopping ability with cheaper FMJ bullets.

Widely available

Hollow point bullets have reputation for under-penetrating.

Relatively expensive

Large and heavy considering the relatively low KE delivered