I have long wondered what is a carbine and what is a rifle.
I did some searching and the most common idea seems to be:

overall, long-barrelled weapons that feature a barrel longer than 20 inches could be called rifles while those with a barrel shorter than 20 inches should be treated as carbines, unless specified otherwise."

Anybody have a better definition?

I would not consider an AR w/ an 18" barrel a Carbine, and IMO 16" 'might' be (is probably?) a gray area as far as AR's are concerned. Case in point, my Knight's Armament LPR (Light Precision Rifle) has an 18" barrel, and DMR's (Designated Marksman Rifles) from most AR manufacturers have 18" barrels as well. Bolt action firearms might (should?) be defined differently than AR's I'd think, which would further blur the line if barrel length is considered the defining criteria.

All carbines are rifles but not all rifles are carbines. The term 'carbine' is used incorrectly at times. Here's the etymology of the word:

https://www.etymonline.com/word/carbine

carbine (n.)

short rifle (in 19c. especially one adapted for mounted troops), 1580s, from French carabine (Middle French carabin), used of light horsemen and also of the weapon they carried; it is of uncertain origin, perhaps from Medieval Latin Calabrinus "Calabrian" (i.e., "rifle made in Calabria"). A less-likely theory (Gamillscheg, etc.) connects it to Old French escarrabin "corpse-bearer during the plague," literally (probably) "carrion beetle," said to have been an epithet for archers from Flanders.

In terms of the AR-15, the 20" configuration with fixed buttstock is a rifle. The ubiquitous 16" barrel, collapsible stock models of AR-15- they, too, are rifles, but can be correctly described as carbines.

Note that historically, the size criteria for a "carbine" has changed significantly over time.

Prior to the modern industrial era, most infantry firearms were quite long, with barrels 30-40+ inches in length. So when "carbines" began making inroads into military service in the 1600s, 1700s, and 1800s, these still had barrels of 25-30+ inches. Shorter, but not anywhere near short by modern standards

As we get into the late 1800s and early 1900s, with the introduction of more modern rifles and smokeless powder, barrel length began creeping down across the board. Most militaries were now fielding standard infantry rifles with 25 to 30+ inch barrels, and "carbines" and "short rifles" were a bit shorter at around 22-25+ inches. For example, 22 inches on a Spencer repeating carbine, 23.6 inches on a Karabiner 98k, 25.2 for the SMLE, etc. Again, these were shorter, but still not short by modern standards.

It wasn't until the mid-1900s that carbine barrels began getting noticeably shorter and routinely featuring sub-20" barrels. For example, 18" on the M1 Carbine, 18.75" on the Enfield Jungle Carbine, etc. This was partly a reflection of the move away from longer-ranged static warfare and into more modern, mobile, shorter-ranged warfare, including fighting in heavy foliage or urban areas, as well as increasingly operating from within motorized and mechanized transport. (See also the rise of the intermediate cartridge, assault rifle, and SMG in military service.)

This shortening trend continued through the Cold War and into the modern era of warfare, where "carbine" barrels are now usually no more than 16ish inches and typically less, and "full size rifle" barrels are usually 20ish inches or a bit more.

Right or wrong, and regardless of caliber I’ve always considered 16” or less a carbine, under 16 with a stock is a SBR or subset of carbine. Without a stock is a pistol, no matter what the barrel length happens to be.

If the firearm in question has more than 16” barrel is a rifle.

I think the intent of the OP was to consider the terminology in historical and military contexts; not within the constraints of contemporary ATF classifications. If that is the case, I agree with that intent.

quote:

Originally posted by KSGM:
I think the intent of the OP was to consider the terminology in historical and military contexts; not within the constraints of contemporary ATF classifications. If that is the case, I agree with that intent.

If historical content was the basis of the OP question, RogueJSK, and Parabellum are undoubtably correct, when I read the OP I didn't feel he was referring to historical context.

The change of historical context could make one wonder.

"carbine" to me implies a relationship; it's the smaller, more compact, handier version of a full size gun. For certain, my K31 Karabiner is not that compared to my AR15 SPR build but it is in comparison to the longer original K11.


M1 vs. M1 Carbine. K11 vs. K31 Karabiner, etc. M16 vs. M4 carbine.

quote:

Originally posted by PGT:
"carbine" to me implies a relationship; it's the smaller, more compact, handier version of a full size gun. For certain, my K31 Karabiner is not that compared to my AR15 SPR build but it is in comparison to the longer original K11.


M1 vs. M1 Carbine. K11 vs. K31 Karabiner, etc. M16 vs. M4 carbine.

We need a “Like” button!

quote:

Originally posted by kimberkid:

quote:

Originally posted by PGT:
"carbine" to me implies a relationship; it's the smaller, more compact, handier version of a full size gun. For certain, my K31 Karabiner is not that compared to my AR15 SPR build but it is in comparison to the longer original K11.


M1 vs. M1 Carbine. K11 vs. K31 Karabiner, etc. M16 vs. M4 carbine.

We need a “Like” button!

“Like”

quote:

Originally posted by PGT:
"carbine" to me implies a relationship; it's the smaller, more compact, handier version of a full size gun.

M1 vs. M1 Carbine.

Except the M1 Carbine is not a smaller version of the M1 Rifle (Garand). They have almost nothing in common mechanically, and were not based on one another.

I mean, if you squint, they might kinda look a little bit like they're related. They both fire a .30 caliber round (although not the same type). They both have a rotating bolt (although not the same type). They both have aperture sights (although not the same type). And they both have an external operating rod (although not the same type).

That's about it for similarities. They really are quite different.

Additionally, there was also the M1 submachine gun, the Thompson, which is also not mechanically related to the M1 Rifle or M1 Carbine.

They're all called "M1" because they're each the first model (M1 = Model 1) of their respective subcategory adopted under the military's new small arms designation nomenclature introduced starting in the mid-1930s.

Here are example of some of the small arms designated by sequential model numbers during the WW2 and immediate postwar era:

Rifle:

quote:

Rifle, Caliber .30, M1 (7.62x63mm Springfield Armory "Garand" semi-automatic rifle)

Rifle, Caliber .22, M2 (.22LR Caliber Springfield Armory bolt-action training rifle)

3?

Rifle, Survival, Caliber .22, M4 (.22 Hornet Caliber H&R survival rifle)

Rifle, Shotgun, Survival, Caliber .22/.410, M5 (.22 Hornet Caliber/.410 gauge H&R survival rifle/shotgun)

Rifle, Shotgun, Survival, Caliber .22/.410, M6 (.22 Hornet Caliber/.410 gauge Ithaca survival rifle/shotgun)

Rifle, Subcaliber, Caliber .30, M7 (7.62x63mm Caliber subcaliber training insert for 75mm recoiless rifle)

Rifle, Spotting, Caliber .50, M8 (12.7x77mm spotting rifle for recoilless rifles)

Rifle, Subcaliber, Caliber .30, M9 (7.62x63mm Caliber subcaliber training insert for 106mm recoiless rifle)

10?

11?

Rifle, Caliber .22, M12 (.22LR Caliber H&R bolt-action training rifle)

Rifle, Caliber .22, M13 (.22LR Caliber Remington bolt-action training rifle)

Rifle, 7.62mm, M14 (7.62x51mm Springfield Armory select-fire rifle)

Carbine:

quote:

Carbine, Caliber .30, M1 (7.62×33mm semi-automatic carbine)

Carbine, Caliber .30, M2 (7.62×33mm automatic carbine)

Carbine, Caliber .30, M3 (7.62×33mm automatic carbine with infrared device)

Submachine gun:

quote:

Gun, Submachine, Caliber .45, M1 ("Thompson")

Gun, Submachine, Caliber .45, M2 ("Hyde-Inland" - very obscure; cancelled and never issued)

Gun, Submachine, Caliber .45, M3 ("Grease gun")

I own an M2 Carbine and have fired an M1 Grease Gun. Also have owned an M50 Reising.

My point isn't that the thing is a scaled down version but rather the name denotes a relationship; M1 vs. M1 Carbine to imply smaller/handier. It doesn't mean it's a chopped down version of the larger based on the same things.

So does a carbine have to have a full size counterpart in the same chambering to be properly defined as a carbine?
Or is it the design and intended purpose that gives it that designation?

quote:

Or is it the design and intended purpose that gives it that designation?

This. I don't think PGT meant that he believes there has to be a "big brother" for there to a carbine. He was merely mentioning another way to assess a rifles potential designation.

quote:

Originally posted by PGT:
"carbine" to me implies a relationship; it's the smaller, more compact, handier version of a full size gun. For certain, my K31 Karabiner is not that compared to my AR15 SPR build but it is in comparison to the longer original K11.


M1 vs. M1 Carbine. K11 vs. K31 Karabiner, etc. uM16 vs. M4 carbine.

.

I think a more accurate comparison would be the Swiss K11 vs. the Swiss 1911 Infantry rifle. The K31 took over for both of them.

Get Both.

My carbine identifies as a rifle.....

quote:

Originally posted by 357fuzz:
I think a more accurate comparison would be the Swiss K11 vs. the Swiss 1911 Infantry rifle. The K31 took over for both of them.

Indeed. Rather than having two standard firearms as before - one long rifle and one short carbine - the Swiss adopted the mid-size K31 across the board to fill the role of both. Other nations were doing the same in the 1930s. For example, the Germans with the K98k/Poles with the Wz. 29 to replace the G98 rifle and K98az carbine, the French with the MAS 36 to replace the Berthier rifle and carbine, the Swedes with the m/38 to replace the m/96 rifle and m/94 carbine, etc. The Brits had led the way with this concept a few decades earlier with the SMLE.

Note that while mid-size firearms like the K98k and K31 were termed "carbines" (K = Karabiner = carbine), they are more accurately referred to in modern terms as "short rifles". They just didn't have a formal military designation at the time for a firearm sized between a long rifle and a short carbine, so because these guns were shorter than their predecessor full-length rifles, they were carbines by process of elimination.

I would say the ‘03 Springfield/M1903 was also a “short rifle” compromise along w/ the SMLE, K98’s, M38’s and others. Went to that to fill one role eliminating the Krag infantry rifle and the Krag carbine and the need for two different rifles/carbines.

Then of course they played around w/ the “Jungle Carbine” variant of the ‘03. I think we would love to have one of those in our collections Rogue.

I think all you can really say with confidence is that a carbine is a short rifle.

It is certainly not correct to say something like "under 18" of barrel is a carbine." I don't know that it has to be a short version of a longer shoulder arm, either. There is no "long" version of an M1 carbine, for example, the M1 rifle being entirely different. No one would argue the M1 carbine is not a carbine.

What "short" is, is likewise a matter with some imprecision built into it.

It is all relative to what a "normal" rifle is, and this is about the most you can say.

This message has been edited. Last edited by: jhe888,