[dead_I_5_0]

hey i have a questio nno these numbers...i know it's a dumb question but i'll never know if i dont' ask...i know that 7.62 is the diameter of the bullet but what is the 54 and 39 (or whatever other number) mean?

 

[ekaphoto]

Eurepean measurments of rounds say 7.62x54 is very simple and standard. (unlike the US) the first number is the bullet diameter, the second number ie 54 is the length of the case in mm.

 

[dead_I_5_0]

thanks for the fast reply....i've been trying to figure that out but noone around could give me a forsure...

-Brian

 

[Kamatz]

To be just a tad anal about it, 7,62mm is exactly 1/3" - and that's the bore diameter. The bullet's usually in the region of 7,8mm to 7,9mm..or thereabouts.

Not that anyone, including me, really cares :lol:

 

[American Rifleman]

7.62X54R means 7.62mm diameter bullet with a 54mm long casing that is Rimmed.

7.62X39mm means 7.62mm diameter bullet with a 39mm long casing which is rimless.

The actual diameter of the ".30 caliber" bullet's made in Soviet block countries is .310

The actual diameter of the standard ".30 caliber" bullets made in the US and other "western" countries is .308

The .303 Brit caliber is actually .311 with a bore diameter of .303.

the 30-30 Winchester caliber is actually .307 with a bore diameter of .30

NONE of these projectiles are safely interchangable!

If you have an SKS or AK style rifle DO NOT put "Winchester Metric" ammo through it!!! If you have a Ruger Mini-30 do not put Wolf or other Soviet Block surplus ammo through it!!! Generally people do it anyway but hey its your rifle and money you do what you want. :wink:

The Rifleman

 

[American Rifleman]

To be just a tad anal about it, 7,62mm is exactly 1/3" - and that's the bore diameter. The bullet's usually in the region of 7,8mm to 7,9mm..or thereabouts.

Not that anyone, including me, really cares :lol:

Just to help stop miss-information from causing hand loading dissasters and guns blowing up in peoples faces i will correct this statement.

7.62mm X 3 = 22.86mm

1" = 25.4mm

7.62mm is not 1/3"

A bullet 1/3" in diameter would be 8.466mm

The Rifleman

 

[ekaphoto]

Now I'm confused. :lol: good point about the soviet 7.62 vs western 7.62. I have wondered if ruger used .308 or 310 dia bbls. I knew us 7.62 ammo was .308, but was understood it was ok to shoot in sks and ak. Not the best accuracy since the bullett is slightly undersize, but safe.

 

[Scharfschütze]

To be just a tad anal about it, 7,62mm is exactly 1/3" - and that's the bore diameter. The bullet's usually in the region of 7,8mm to 7,9mm..or thereabouts.

Not that anyone, including me, really cares :lol:

I think what he meant was .300" not 1/3"

1/3"=.333 or 8.466mm as Rifelman stated.

 

[American Rifleman]

Now I'm confused. :lol: good point about the soviet 7.62 vs western 7.62. I have wondered if ruger used .308 or 310 dia bbls. I knew us 7.62 ammo was .308, but was understood it was ok to shoot in sks and ak. Not the best accuracy since the bullett is slightly undersize, but safe.

There is an indoor range here that i frequent for pistol shooting. They also allow rifles in intermediate calibers. So i thought i would introduce a friend to shooting with an SKS. Since it is an indoor range it uses a bullet trap which is steel and captures a bullet and spins it around inside a trap untill it stops. Well; since he had people using steel core rounds and messing up his bullet traps he no longer allows people to use there own ammo. They have to buy his ammo. So i bought a few box's of Winchester "Metric white box" 7.62X39mm ammo and we started shooting. I noticed it was not cycling the action at all and i had the range master observe the action while i fired a round. He said that it was not cycling the action at all. So with the range masters permision i used a few rounds of my own ammo ( Wolf 122gr ) and it worked fine. After this i went home and did some research on the net on AK and SKS sites. Apparently this is a wide spread problem with using American made 7.62X39mm ammo in Soviet caliber weapons designed for the ever so slightly larger bullet.

The Rifleman