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View Full Version : 7.62mm versus .308 ammo


Eppie
January 27, 2010, 02:24 PM
Hi Guys,
I recently received, but haven't fired yet my DPMS Sportical (see http://www.dpmsinc.com/store/products/?prod=5355 ). I'm waiting on my Leupold scope to arrive.

I went down to the local Academy store and bought a few boxes of Winchester 7.62mm 147 gr. ammo. The were selling for $15.00 a box all the ..308 ammo was selling for $33-35 a box. One of the many reasons I bought this rifle was that the ammo is plentiful and reasonably priced. But to sell for less then half of the .308 which basically the same bullet it has me wondering what am I missing here?

Anyone out there with answers or similar experiences?
Kindest regards

Joe:confused:

Lavid2002
January 27, 2010, 03:05 PM
There practically the same rounds...the difference you might be seeing is from price of materials....
The .308 is considered to be a hunting round and those 33 dollar a box cartridges you are seeing are more than likely topped off with hunting bullets like nosler silvertip, hornady, speer, etc.....308 often has higher pressures because it is a hunting round.

7.62 NATO, or 7.62x51 is a military cartridge. If im not mistaken it has the exact dimensions of the .308 cartridge. However they often have crimped in primers (So they can be shot from machine guns without risking a blown out primer which could cause the weapon to jam) They often use surplus bullets. Standard full metal jacket 150 grain boat tail bullets. Nothing special. I buy the surplus bullets and use it for plinking. If I want accuracy I buy the expensive bullets and hand load my own cartridges.

Answer the question?

Edit: also...at the store that I work out we have a similar scenario. PMC and WOLF 55 grain FMJ .223 goes for 8-10 bucks a box. While remington, and winchester hunting loads are upwards of 24 DOLLARS ! FOR .223! Wow.... It does make a huge difference in price. Its all about the application.

Jimro
January 27, 2010, 03:33 PM
The differences between 7.62x51 and 308 Win are academic. Anyone who says differently is selling something.

There are no pressure differences until you get into Hornady's "Light Magnum" line, or whatever they are calling it now.

Jimro

artsmom
January 27, 2010, 03:42 PM
The differences between 7.62x51 and 308 Win are academic. Anyone who says differently is selling something.

There are no pressure differences until you get into Hornady's "Light Magnum" line, or whatever they are calling it now

My experience has been otherwise. I had some Hirtenberger surplus ammunition that would lock up Remington 788 or a Savage 99 tight as a safe. (note that neither is a front locking bolt action, which probably would have made a difference in bolt spring and subsequent extraction).

That isn't to say all 7.62x51 is higher pressure or all .308 Winchester is higher pressure, just that every ammunition / rifle combination can't be covered by a blanket statement.

freakshow10mm
January 27, 2010, 03:44 PM
Generally 7.62 NATO is loaded to a lower chamber pressure than .308 Win. Dimensionally, they are the same exact cartridge, just different chamber spec.

Chipperman
January 27, 2010, 03:47 PM
The were selling for $15.00 a box all the ..308 ammo was selling for $33-35 a box.

The .308 were probably with hunting bullets, as stated above. If they were just FMJ, the store was really scalping.

PhilC
January 27, 2010, 03:54 PM
Thanks, everyone, for sparing me the ".308 blows up 7.62 NATO guns," or vice versa.

Eppie
January 27, 2010, 04:45 PM
I want to thank everyone for taking the time to responde to my question. I really appreciate it.

Joe:)

Jimro
January 27, 2010, 05:17 PM
That isn't to say all 7.62x51 is higher pressure or all .308 Winchester is higher pressure, just that every ammunition / rifle combination can't be covered by a blanket statement.

I agree, I've had Federal blue box ammo give me pushed out primers and hard bolt lifts in 308. After one box I stopped shooting Federal Power Schock...

Jimro

FALPhil
January 27, 2010, 08:23 PM
Generally 7.62 NATO is loaded to a lower chamber pressure than .308 Win.
Generally, this is not a true statement.

http://thefiringline.com/forums/showthread.php?t=326877

Composer_1777
January 27, 2010, 08:58 PM
I prefer the 308 spec chambers. Wolf 308 is horrible, the federal SP's work out fine although with the soft point sometimes the chamber doesn't load. Rifles are always gonna have certain kinks. Just like a car blowing stuff up inside of metallurgic parts is always gonna have something go wrong.

On my FNAR i only use 308 b.c. that's what is specified. I'd suggest sticking with 762 since that is the specified round,

freakshow10mm
January 27, 2010, 09:48 PM
Generally, this is not a true statement.
Riiiiight.:rolleyes: If it makes you sleep better.

FALPhil
January 27, 2010, 09:55 PM
Riiiiight. If it makes you sleep better.
Hey, I did the research. What did you do?

GeauxTide
January 27, 2010, 10:00 PM
The 308 Winchester IS the 7.62x51. The SAAMI specs are identical. As mentioned above the military rounds are FMJ with crimped bullets and primer pockets. There was no confusion over any "difference" in the 30-06 in the Garand and 1903 and sporting round.

jman841
January 27, 2010, 10:11 PM
There are 2 major differences. First, is head spacing. Where they measure it from in a military rifle is different than a civilian .308. Number 2. Case capacity in the military round (7.62x51) is less than the civilian round due to increased brass wall thickness. This is only important if you are reloading. I do reload military surplus brass and typically use 2-3 less grains than stated for the .308 win load.

I'm am not sure on the effect of pressure but, i have shot some of the winchester 7.62 x 51mm 147 grain in a .308 chambered rifle and did notice that some of the rounds showed slight signs of over pressure. (the primers were starting to push out the back.) However, when i reload them with my conservative loads (usually between 40-43 gr of IMR 4064) they do not show any signs of over pressure. however, i did take some measurements with calibers to compare the resized brass to the original winchester military brass and it does change considerably after firing and resizing.

For non reloading practical purpose, the two are interchangeable