Confusion about ammunition for my Norinco M14s

[AchiesBunker]

Hi,

I just recently purchased a Norinco M14s rifle. It is my first rifle and I haven't had a chance to fire it yet. I'm on my way to the cottage this weekend and i'm hoping to have a chance to AT LAST fire my new rifle.

In my search for ammunition I've read so many articles that now I'm seriously confused. (The articles links I've found in threads were awesome - thank you to those contributors, It's just really confusing as you are left with questions about safety).

My rifle is chambered for a 7.62 x 51 NATO cartridge but I keep reading that you can use a Winchester .308. I've also read that Winchester .308 isn't the same as 7.62 x 51. I'm confused about this. I've read that you can use the 7.62 x 51 cartridge in a W .308 chamber because of the SAMMI/CIP rated pressure is higher, however you might end up with problems using a .308 cartridge in a 7.62 x 51 chamber. There are also discussions about commercial brass vs military brass,cartridge length, load capacity???

I've read that you can get around this by using a Winchester cartridge that doesn't exceed the rated PSI of my rifle which I understand to be 50 000 PSI .

Should I be trying to buy surplus military ammunition?

Can someone please offer some guidance?

Thanks in advance.
AB

[surplusshooter]

I believe you have it backwords- you can shoot a 308 in 7.62x51 but not other way around. Military builds to higher pressures. Could be wrong tho. Cheapest would be buying bulk.

[AchiesBunker]

Hey surplussshooter,

Thanks for the ultra fast reply! I will double check.

[fiddler]

You can shoot both in your M14/305 with no problem. Buy away. Shoot away.

[Sherlock Gnomes]

They are close. If reloading try to use lighter loads in 308 offerings.

[Turkinator]

I believe you have it backwords- you can shoot a 308 in 7.62x51 but not other way around. Military builds to higher pressures. Could be wrong tho. Cheapest would be buying bulk.

.308 is higher powered than 7.62x51nato while 5.56x45 is more powerful than .223
You should get your rifle headspaced before you begin to use .308, especially crap like Tulammo .308 otherwise you'll get complete case head separations and popped primers. Barnaul makes a 7.62x51mm fmj and soft point if youre not able to find any surplus chinese ammo.

[AchiesBunker]

Hi,

Okay, here is the article I read. Reference: http://www.6mmbr.com/308Win.html (awesome info!)

...

.308 Win vs. 7.62x51--The Straight Scoop
Before we go much further, we want to address the oft-posed question "Are the .308 Winchester and 7.62x51 NATO one and the same?" The simple answer is no. There are differences in chamber specs and maximum pressures. The SAMMI/CIP maximum pressure for the .308 Win cartridge is 62,000 psi, while the 7.62x51 max is 50,000 psi. Also, the headspace is slightly different. The .308 Win "Go Gauge" is 1.630" vs. 1.635" for the 7.62x51. The .308's "No-Go" dimension is 1.634" vs. 1.6405" for a 7.62x51 "No Go" gauge. That said, it is normally fine to shoot quality 7.62x51 NATO ammo in a gun chambered for the .308 Winchester (though not all NATO ammo is identical). Clint McKee of Fulton Armory notes: "[N]obody makes 7.62mm (NATO) ammo that isn't to the .308 'head space' dimension spec. So 7.62mm ammo fits nicely into .308 chambers, as a rule." You CAN encounter problems going the other way, however. A commercial .308 Win round can exceed the max rated pressure for the 7.62x51. So, you should avoid putting full-power .308 Win rounds into military surplus rifles that have been designed for 50,000 psi max. For more information on this interesting topic, read the following articles: Gun Zone's 30 Caliber FAQ; Cruffler.com Technical Trivia, June 2001; and last, but not least, Steve Redgwell's .308 vs 7.62x51 Analysis, which really provides a definitive explanation. Reloaders should also note that military ammo often is made with a thicker web. Consequently the case capacity of 7.62x51 brass is usually less than that of commercial .308 brass. You may need to reduce recommended .308 Winchester loads by as much as 2 full grains, if you reload with military 7.62x51 brass, such as Lake City or IMI.
Ca

...

I've reread and I interpret the same way. Admittedly, I'm a NOOB! Here are other references: http://www.303british.com/id36.html

What is your interpretation?

Also, Can anyone advise on cheap commercial rounds and 'Slam Firing'?

Thanks again,
AB

[AchiesBunker]

Hey Turkinator,

Seriously, thanks for the quick reply. I love this website. I know nothing of headspacing? Can you elaborate and is this a DIY or does it require a seasoned gunsmith?

[fiddler]

Your Norinco M305 is a new rifle. it will handle pressures of either bullet designation. The problem is generally with much older rifles.


Slam firing is not caused by cheap ammo, its cause by improper cleaning and maintenance. Some people accuse soft primers to contribute to this problem, but if the firing pin properly retracts, it will not hit the primer to ignite the cartridge.

[AchiesBunker]

Hi Fiddler,

THANKS so much for the reply! I'd like to buy some ammo tomorrow. When I buy Winchester .308 ammo, should I avoid the anything over 160 grain? I'm curious to know if cartridge pressures are on the box?

Also, thanks for the heads up on slam firing! I'm going to look into that.

Thanks,
AB