7.62x51 vs. 7.62x39

[unklekippy]

The R in 7.62x54R stands for Remington. Kip

 

[DieselScout]

In general, if you see an "R" in the designation, it is a cartridge designed under the "inch" standard, but converted to metric measurements for the european market..

As stated before the R stands for rimmed, it has nothing to do with where the ammunition was designed. The 7.62x54R was never designed on the inch standard, it was designed by the Russian empire in 1891. Coincidentally it is still used by national armies today, making it the longest running military caliber in history. The .357 mag just happens to be a rimmed cartridge, so it get the R designation.

The R in 7.62x54R stands for Remington. Kip

You're not being serious?

It stands for rimmed or originally for Russian depending on who you talked to.

 

[unklekippy]

No, I was not being serious. Why would Remington have anything to do with this Russian(though it does in fact stand for rimmed, not Russian) round? I guess I should have put a little smiley face icon or something. The best jokes are the ones you have to explain. Kip

 

[DieselScout]

No, I was not being serious. Why would Remington have anything to do with this Russian(though it does in fact stand for rimmed, not Russian) round? I guess I should have put a little smiley face icon or something. The best jokes are the ones you have to explain. Kip

LOL yeah that would have helped.

 

[theguncrank]

The original designation of the 7.62 bullet was "3 line calibre" based on a Russian Imperial measurement system, which varied slightly from the English Imperial measurement system. The Russian liniya (line) was defined as 1⁄10 of the diuym (inch) from the 16th to the early 20th century. Even after the superior properties of the metric system were recognized for technical pursuits, existing tools frequently favored the use of customary units. Thus a 7.62 mm caliber round seems numerically arbitrary, until it is realised that 7.62 mm is (actually approximately) 0.3 inches, .30 cal or three-lines. The 1891 Russian Mosin-Nagant rifle is known as the "three-line rifle" in Russian. Although rarely referred to as such, the 12.7 mm HMG round is a "five-line" round.

(Thanks, Wikipedia)

 

[theguncrank]

Why would Remington have anything to do with this Russian

In 1915 the Tsar's government ordered 1,500,000 M1891 infantry rifles and bayonets and 100,000,000 rounds of 7.62x54 mm ammunition from the American firm Remington-UMC... That's a good run, and one imagines the Remington moniker could at one time have been associated with the cartridge, correctly or not.

 

[Confederate Hammer]

So, what I'm gathering is the answer to my original interrogative is a 7.62 round is basically a 30 caliber.

Thank you everybody for your responses.

 

[DieselScout]

So, what I'm gathering is the answer to my original interrogative is a 7.62 round is basically a 30 caliber.

Thank you everybody for your responses.

Yep 7.62mm ÷ 25.4 mm/inch = 0.30 inch or 30 caliber.

 

[blitz]

.310 diameter if that is what you are asking

 

[Nwcid]

.310 diameter if that is what you are asking

No. 7.62mm = .30" as the math above shows.............

 

[trainsktg]

So...why do they call 8mm '8mm' when its really 7.92mm?

Who's on First ?

Keith

 

[blitz]

i may have read the question wrong it appeared to me that he was wondering the diameter for the projectile.
running 30cal .308 diameter projectiles through a 7.62x39 isnt gonna be as accurate as .310 diameter projectiles

 

[Toxic6]

Mauser rounded up?

 

[sadiesassy]

OK this makes more sense

It really does come down to the variation in design as to what parameter was used to measure the caliber.
Also worth noting is that caliber is often a measure of land diameter, not groove diameter, so a 7.62x39mm/7.62x54mmR bore diameter is indeed 7.62mm (.30, inline with the old 3-line designation) at its narrowest, but the grooves are 7.92mm, so the bullet diameter needs to be larger than the narrowest measurement of the bore.
7.62x51mm is actually a .308 (7.82mm) bullet diameter.
Again, it's just what point was used for measurement, much like the 45 Colt/.45ACP and 9mm variations mentioned above.

 

[HollisOR]

Nomenclature is just a name they place on a round. Is Bobby a gal or a guy? There are three different size 8mm that I know of. Best bet is to pick up a reloading book and read.

 

[krivey]

God I love this forum. So much info. I agree 100% with hollisor. Get a reloading manual or five and read on each caliber. Each one has it's own unique story on how and why it was designed and what the actual dimensions are.

 

[SurvivalistSong]

Right.



Okay, but my main question still is: what makes a 7.62x51 a .308? and what mathematical calculations do I use to come up with that :huh:
And what would a 7.62x39 be?

.30 inches = 7.62 mm.

it's simply a conversion factor between the metric millimeter to the stupid (forgive me) american system of inches.

.308, that extra +.008 is just a variation in bullet design. Just like how the 7.62 russian is .311 inches. The diameter of the 7.62nato/.308 is about the same as the 7.62x54R.



R stands for rimmed, not Russian as some people believe. It is a RIMMED cartridge, which is an outdated design, but it is still used in modern weapons such as the beloved dragunov, PSL, Pecheneg machine gun, etc.

The 7.62x54mmR is the oldest cartridge in military use today. It has been used for over a century.






Ballistically and practically speaking, the 7.62x54mmR is in between the performance of a 7.62NATO/.308 and a .30-06.




To be honest, the 7.62x54mmR is my personal favorite battle rifle full-size cartridge. It is cheap due to large amounts of surplus availability, and it is extremely effective in both combat and shooting imaginary paper badguys at the range.

These are the same reasons the 5.45x39 russian round for the AK-74 is my favorite intermediate cartridge.


Basically, the Russians know how to make practical, effective, and cheap weapon systems. Better than any other country in the history of firearms.

If you want high-tech gadgetry, then ofcourse American guns top all others (argueably better than current german and belgian small arms).

 

[madcratebuilder]

In the European countries they use bullet diameter and CASE length (not overall length) in metric. So for .30 caliber they call it 7.62. So ALL of their .30 caliber guns including pistols have names like 7.62x25, 7.62x39, 7.62x51, 7.62x54r (r is for rimmed rounds). They dont come up with cool little marking names like we do.

Does that mean I have to peen out all my ,303 Brit markings and restamp them 7.7mm:huh:

 

[jerman1964]

yes. deprime them first.

 

[hermannr]

Come to think of it, you may be right on the "rimmed" part