7.62 x 39 vs. 7.82 x 51 (.308)

[Cowboy_mo]

Perhaps I'm just dense but I don't why anyone would want the 7.62 x 39 instead of the .308 EXCEPT that they want an AK.

When you are talking 0.2 of a mm in bullet diameter less but you also give up 12 mm of case length for powder, it doesn't make sense to me.

Now, if is because "I just want something different" then I completely understand. But, if there is a REAL difference between the two I would like to know.

 

[jmr40]

For the most part you're right. The X39 will have less recoil and offers some advantages in a semi, or full auto rifle. The X51 has just a bit more recoil and added rifle weight that makes it less appealing in an auto.

Most people who want the X51 choose bolt guns. But the X39 in a bolt gun is easier to use in a suppressed rifle, and some guys with a large stock of X39 ammo just want another gun in a bolt rifle that will shoot the same ammo.

 

[ligonierbill]

Well, you have it backwards on diameter. They're both nominal 7.62, but the .308 is actually 0.308 while the AK round is 0.311. A better comparison is the 7.62x54R Mosin-Nagant round, also 0.311 (usually). The AK round is a moderate power and recoil cartridge. The others are "full power".

 

[Erno86]

Probably my next bolt gun will be a CZ 527 in 7.62x39... which will be used primarily as my range gun, that would shoot steel targets. The ammo is compatible with a couple of my AK's, can shoot deer and hogs, reasonably accurate up to 200 yards and the cheapest centerfire ammo on the market.

 

[Cowboy_mo]

Thanks for the responses.

They're both nominal 7.62, but the. 308 is actually 0.308 while the AK round is 0.311.

I would agree they are both nominal .30 caliber. What I don't understand is how 7.62 mm can be .311 inches. When I put 7.62 mm in the conversion program it comes out 0.3 inches. When I put .311 inches in the conversion program it comes out 7.8994 inches. I guess that makes it more of a cousin to the 8mm. Almost forgot, when I put .308 inches in the conversion program it comes out 7.8232 mm which is why I labeled it 7.82.

 

[dahermit]

Perhaps I'm just dense but I don't why anyone would want the 7.62 x 39 instead of the .308 EXCEPT that they want an AK.

When you are talking 0.2 of a mm in bullet diameter less but you also give up 12 mm of case length for powder, it doesn't make sense to me.

Now, if is because "I just want something different" then I completely understand. But, if there is a REAL difference between the two I would like to know.

Whoa there cowboy! The difference between a 7.62x39 and a .308 is two thousandths of an inch, not two tenths of a millimeter.
I currently have a 7.62x39 in a Ruger bolt action and have had a Ruger .308 Target Varmint rifle. The difference is that the 7.62x39 fills a different nich than the .308. My Varmint Target Ruger in .308 was my long range "sniper rifle" that could be used for precision, long range varmints and in competition where as my 7.62x39 was a utility gun for targets of opportunity at relatively close range in my backyard. The other big difference is RECOIL. Recoil in the 7.62x39 was negligible despite being a lightweight gun. On the other hand, even though the Ruger Target Varmint (.308), had a heavy barrel and heavy laminated stock, shooting it from the bench proved to be somewhat unpleasant.

 

[tangolima]

0.3" (7.62mm) is the bore (land) diameter. They all have the same bore diameter. But when they cut the rifling grooves, they have different ideas. The Americans cut it 0.004" deep, while the Russians cut it 0.005" to 0.006" deep. So we have 0.308" groove, and hence bullet, diameter, and they have anything from 0.310" to 0.312".

-TL

 

[oldscot3]

My understanding is that the 7.62x39 had its origins in WW II. The Nazis realized that standard infantry weapons weren't ideal when the fighting moved from the fields of Europe to the towns and villages. They shortened the 8x57 and developed a mid-range assault weapon.

When the Russians overran them they realized the value of such a system and quickly did what they did best at that time... copied it, though their version was simplified to make production cheap and fast.

Now, this is a brief, general synopsis, so you historians here, feel free to edit and correct for the purpose of accuracy.

BTW the 308 is just a shortened 30 06, but our guys didn't exactly put it in a short, handy package with the M1. The idea was somewhat similar though, certain powders were used, and they didn't need the extra case space to launch 150 gr. bullets at the ranges deemed practical for foot soldiers.

 

[ligonierbill]

Cowboy, the folks who name calibers seem to go out of their way to confuse us. A "32" caliber pistol shoots 0.311 bullets, a "38" shoots 0.357, and a "44" shoots 0.429. Oh, and a .303 Enfield shoots 0.311, like the Russian 7.62s. Why? Danged if I know, but you can't go strictly by the nomenclature.

 

[Jimro]

Perhaps I'm just dense

Perhaps.

There are plenty of good reasons for wanting a lower recoil center fire rifle. The CZ527 is a popular rifle for a lot of good reasons. Cheap ammo, low recoil, adequate short range hunting applications...

Jimro

 

[TMD]

Why is the .45acp .451 and the .45-70 .458?
How come the .38spl and the .357 are both the same diameter?

Sometimes its all in the name.

 

[emcon5]

Well, for starters the 7.62x39 is an intermediate cartridge, (like the 5.56 NATO) and the .308 is not. If you want a light, handy rifle with mild recoil, and adequate power for most North American game at reasonable ranges, it may suit your needs. As a bonus, target ammo is cheap.

The real difference is the .308 is a heavier higher pressure round that shoots a heavier bullet faster.

 

[Cemo]

Not considering military uses of these two cartridges, for plinking or target both are good, however the .308 may leave some with sore shoulders. For deer hunting, in a good rifle, the 7.62x39's accuracy and 2200-2300 fps velocity is very effective out to 150-200 yards. If you only hunt in the woods, what else do you need? My daughter loves my CZ. It can also shoot the cheap steel case ammo for practice. It would be a good starter for a recoil sensitive youth too. Once you move out past 150-200 yards for deer you need a flatter shooting gun with more energy, i.e. .308, .270. 300 mag and similar cartridges.

 

[SaxonPig]

The 308 is clearly more powerful. Not everyone wants the more powerful one. The Commie round works in a more compact platform and that may appeal to some depending on intended use.

 

[oldscot3]

When it comes to cartridge nomenclature, that really is a can of worms. Factors include inches versus millimeters, bullet diameter versus rifle bore (groove v.bore), indications of case length or not, factory introduced versus military versus wildcat origins. And the list goes on.

In my life, I found they the quickest way to learn the important details was to take up handloading.

 

[T. O'Heir]

"...They're both nominal 7.62mm..." 7.62 mm is the bore diameter. The size of the hole drilled in the barrel blank.
Never try and figure out why any cartridge is called what it is. It will give you an aneurysm. For example, the 7.5 x 55 Swiss use the same bullet diameter as the 7.62NATO. So does the 7.5 x 54 French. The 7.62 x 54R uses the same bullet diameter as the .303 British, nominally .311". All of 'em are still .30 calibres.
'.308' is the marketing name for the commercial hunting cartridge. 7.62 x 39 is the Warsaw Pact(read Russian) name for their military battle rifle cartridge.
"...the folks who name calibers..." Are mostly marketing types for commercial cartridges. Military stuff is a secret. Well, it used to be.
"...difference between a 7.62x39 and a .308 is two thousandths of an inch..." 3 thou of bullet diameter, but it doesn't matter.

 

[Jim Watson]

As far as nomenclature goes consider that the
.218 Bee, .219 Zipper, .220 Swift, .221 Fireball, .222 Remington, .223 Remington, .224 Weatherby, and .225 Winchester
ALL have nominal .224" groove diameter/bullet.

But the .22 Remington Jet and .22 Savage High Power don't. (.222" and .227")

 

[Gunplummer]

I never tried .224 bullets in my HiPower, but some guys say they shoot OK. I have shot pounds of .308 bullets in .311-.312 bores with really good results. I have had .308 and 7.62x39 semi-autos. The biggest difference for me is ammo cost and rifle weight. Hard to beat the weight of an AR style rifle chambered in 7.62x39 with any semi chambered in .308.

 

[Screwball]

Is there really a need for a reason to pick a .308 or 7.62x39mm? I got into guns because I don't like having to compromise... I want one of everything. [emoji41]

I picked up my Yugo SKS prior to my WASR. An AK pattern rifle, especially with the uncertainty with the next election, should be on everyone's short list. Very neat design. Round is kind of cheap (shooting stopped being cheap a few years back), and it does a little more than 5.56mm. I didn't buy into them because there is .003" more bullet... but because the SKS and AK pattern are chambered in it.

I wasn't a huge fan of the .308. Have a M1903 and a Garand, so more stocked in .30-06. But I've had my eye on an Ishapore 2A1 for a little bit, and finally pulled the trigger. With the gun collection getting to a x9, I do want to buy another to round it off... which may or may not be an M1A (if I'm going to stock .308, might as well go into it). The performance of .308 isn't an intermediate cartridge like 5.56mm or 7.62x39mm... but a full powered rifle cartridge. It goes back to the time when the men were men and the sheep were scared. [emoji23] But in all seriousness, if you want to go past the effective range of 7.62x39mm, a .308 is the next logical step up. Plus, you can still do an iron sighted semi-auto rifle. Or you can go into a precision bolt action (if I did a long range bolt gun, I'd likely do 6.5mm Creedmore).

 

[turtlehead]

Why would you want a putter when you can have a driver?

I just don't understand.