There are hundreds of calibers to choose from when deciding on your next firearm, so how to choose? Like it or not, the most common, household names like 9mm are not the best performing rounds out there. Many factors determine how popular and widely available a caliber will be, including,
- military use
- good marketing
- adoption by many firearm and ammo manufacturers
- rave reviews from respected figures in the firearms community
I put performance at the end of the list for a reason, it’s just not the main deciding factor.
The big three: when in doubt, use what the Army uses
Three of the most widely available rifle calibers have been US military standard issue, .30-06, .308, and .223. Yeah, they have some fancy metric names but these are actually the original designations. The first two are outstanding performers. The US military introduced the .30-06 in 1906 to make sure that it had the firepower to outgun rifles like the Mauser 1983 used by the Spanish in the Spanish-American War. The .308 was a failed attempt to adapt the .30-06 for select fire after WWII. It turned out to be an outstanding performer in long-range marksmanship and is still used in NATO sniper rifles. Both the .30-06 and the .308 are legendary rounds, two of the most popular in America and around the world. The next standard issue US military rifle round is more contentious, the .223. The UK wanted to bring NATO into the assault rifle age with the FN FAL chambered in the superior .280 British, but the US military doesn’t like being told what to do, so AR-15 in .223 it was. The rifle is a runaway success, but the round, designed to be light, fast, and easy to pack in bulk definitely has its detractors. It doesn’t really excel in anything.
It’s a similar story with the military’s move from the 45 ACP thumper to the 9mm. Both the .223 and the 9mm are considered by many to be pea-shooters and major missteps in military procurement. Nevertheless, thanks to Uncle Sam’s seal of approval, these are two of the most ubiquitous rounds on the civilian market today. One of the best handgun calibers is 10mm, which was developed to outgun both 45 ACP and 9mm in a semi-auto handgun. The FBI trialed it after the tragic 1986 Miami shootout, but weaker trainees found it hard to manage. Instead of giving them more training, the FBI developed the .40 S&W, which is still better than the 9mm.
Does standard issue mean best of the best?
As a civilian shooter, your priorities are probably not to have something that will outgun the Spanish, provide .30-06 performance in full-auto, be easy to pack in bulk into battle, or be easy on the weak. If you’ve ever built an AR-15, you know that mil-spec components are solid options, but for a bit more cash, you can get something much better. The same is true with calibers. There are of course rounds that have been designed from the ground up to meet civilian needs, but even in that category, the most popular options are not the best performers. Legendary options like .270 and .243 come to mind to out-perform the .308, depending on the specific scenario. If ‘go big or go home’ is your motto, to outgun .30-06, anything with a ‘Weatherby’ and ‘Magnum’ in the name will do the trick, especially if there’s also a ‘.300’ in it. The .300 Winchester Magnum is also hard to beat.
It’s not hard to do better than .223
It’s disconcerting that the calibers for taking out fools are the same as those for taking out varmints. It’s not hard to find something that performs better than .223, check out .204 Ruger or 6.5 Creedmoor. For whatever reason, 6.5 appears to be a ballistic sweet spot. Rounds in this range usually offer long, thin bullets, giving you a great ‘ballistic coefficient,’ meaning they cut through the air efficiently, shooting straight and flat without getting bucked by the wind. Many argue that they hit well above their weight. Think 6.5x55mm Swedish, .260 Remington, 6.5 Grendel, or even its daughter case, .224 Valkyrie. Unlike the military rounds mentioned above, you’re not going to find these in every single little sporting goods shop. I know of no round with better ballistics than the .260. Remington failed to market it well when it was introduced and other manufacturers didn’t take it up, so it faded away everywhere but in long-range competition results. Legendary civilian rounds like .270 Winchester enjoyed solid marketing, brought adoption by manufacturers, and rave reviews by leading figures in the firearms community. It is a great performer, but, like .308, it’s not the best.
Availability is a major issue in picking the best caliber
As performance and popularity are not in perfect alignment, if you insist on going for the ultimate cartridge in a given category, you’re probably going to face availability issues. Sure, every so often there is a general, nationwide ammo shortage anyway. One way around this is to reload. Get a reloading press and other equipment, stock up on brass, invest in an annealer, and you’ll be pretty self-sufficient. If you cast your own bullets from old tire weights, all you need to worry about is powder and primers.
Check out our guide to reloading.
One way to avoid agonizing over which caliber is best is to just go 12 gauge. You sacrifice range for unrivaled versatility. Most deer are shot not far past the effective range of a slug, and a slug will drop anything you place a decent shot on. Buckshot is a great option for home defense, but again, the most popular, old military option, double-aught, isn’t as good as #1 buckshot, which will give your assailant more pellets and more lead to contend with.
The bottom line: it’s the shooter not the round
After all that nitpicking, here’s the bottom line. If you go with a well established, proven caliber in one of these categories,
- Rifle for varmints/defense
- Rifle for mid-sized game
- Rifle for large game
You can save the headache of obsessing over which caliber to choose. Training and practice will make vastly more difference in how effective your shooting is than caliber choice. Availability is an important factor to consider when choosing the ‘best caliber.’ So if a good deal on a gun in a proven caliber comes up, don’t fret, pull the trigger. Get yourself trained and put in some serious hours at the range and you’ll be outgunning the best of them. Have fun and shoot safe!