308 / 7.62 ammo difference
- Thread starter elvis3006
- Start date
- Location
- Oil Country
7.62 x what?
7.62 x 51 actually IS .308 (essentially), so as long as you're not asking if you can feed .308 into a CZ-858 etc that's chambered for 7.62x39 or a Mosin etc chambered in 7.62 x 54R then you're good to go.
7.62 x 51 actually IS .308 (essentially), so as long as you're not asking if you can feed .308 into a CZ-858 etc that's chambered for 7.62x39 or a Mosin etc chambered in 7.62 x 54R then you're good to go.
Yes. Pressure limits and dimensions of the two calibers are about the same.
However - 308 ammo is available with heavy bullets loaded with slow powder. Slow powder has higher pressure at the gas port than the faster powder used in light bullets. This can be a problem if the 7.72x51 military rifle does not have an adjustable gas port. The higher pressure can beat up the operating system.
However - 308 ammo is available with heavy bullets loaded with slow powder. Slow powder has higher pressure at the gas port than the faster powder used in light bullets. This can be a problem if the 7.72x51 military rifle does not have an adjustable gas port. The higher pressure can beat up the operating system.
canucklehead
CGN Ultra frequent flyer
- Location
- Calgary, AB
The Norinco is actually 7.62x51, not .308.
AND - it runs flawlessly through my 1919A4, so you should be good.I run it at 3 clicks out, and have had zero issues.
I am editing this post to remove my opinion as I am underqualified to comment. I have read posts from knowledgable and respected members of CGN, such as Ganderite, who fell on both sides of the argument. I will leave the debate to the better equipped.
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'a firearm chambered for the NATO cartridge will accept the commercial caliber as well, but it is not recommended to go the other way. The NATO cartridge's slight differences in sizing and pressure can cause catastrophic failure in a firearm chambered for the commercial caliber. "
Nonsense. The ammo is almost identical. Pressures and dimensions are basically the same.
The 308 chamber and the NATO chamber can differ, with the 7.62 being larger than the average 308.
A NATO case tends to have a slightly higher base (thicker web) than a 308 case. There are some models of 7.62 rifles that have a relief cut in the chamber mouth for a feed ramp. This leaves part of the case head unsupported. I have seen "accurized" M14s with aggressively shaped ramps that left a lot of case unsupported and there have been reports of these kinds of rifles blowing out case heads.
Such incidents usually involve someone switching from military to commercial cases and then blowing a case (wrecking the rifle). Although it could be argued that the problem was shooting commercial brass in a military chamber, I would rather call it an unsafe rifle. A military case is no guarantee of heavier brass or a thicker web. The lightest brass I have ever encountered was a lot of Winchester made military brass; and the lowest web I ever saw was also on a military case.
I have only personally been involved in one such blow up. Funny enough, it was a military case that blew. It was a round of Santa Barbara military (Spanish, I think). It was in a bolt action rifle that was put together with more case head unsupported than it should have. It worked for a long time with many kinds of ammo, until it was fed some Santa Barbara. An investigation discovered the unsupported case head and a sectioned sample of Santa Barbara (military Berdan) brass disclosed the lowest web we had ever seen. Much thinner than on a typical commercial case.
I have spend a lot of time in a lab, testing both military and commercial ammo. Both types have typical pressures around 55,000 psi, with some lots running over 60,000 psi. The highest military I ever saw was one lot of IVI 7.62 that was around 62,000 and the highest 308 was a lot of Winchester Supreme Match at about the same pressure. I tested both lots because there had been complaints about pressure problems. Both were within the allowable limit - but just barely.
Nonsense. The ammo is almost identical. Pressures and dimensions are basically the same.
The 308 chamber and the NATO chamber can differ, with the 7.62 being larger than the average 308.
A NATO case tends to have a slightly higher base (thicker web) than a 308 case. There are some models of 7.62 rifles that have a relief cut in the chamber mouth for a feed ramp. This leaves part of the case head unsupported. I have seen "accurized" M14s with aggressively shaped ramps that left a lot of case unsupported and there have been reports of these kinds of rifles blowing out case heads.
Such incidents usually involve someone switching from military to commercial cases and then blowing a case (wrecking the rifle). Although it could be argued that the problem was shooting commercial brass in a military chamber, I would rather call it an unsafe rifle. A military case is no guarantee of heavier brass or a thicker web. The lightest brass I have ever encountered was a lot of Winchester made military brass; and the lowest web I ever saw was also on a military case.
I have only personally been involved in one such blow up. Funny enough, it was a military case that blew. It was a round of Santa Barbara military (Spanish, I think). It was in a bolt action rifle that was put together with more case head unsupported than it should have. It worked for a long time with many kinds of ammo, until it was fed some Santa Barbara. An investigation discovered the unsupported case head and a sectioned sample of Santa Barbara (military Berdan) brass disclosed the lowest web we had ever seen. Much thinner than on a typical commercial case.
I have spend a lot of time in a lab, testing both military and commercial ammo. Both types have typical pressures around 55,000 psi, with some lots running over 60,000 psi. The highest military I ever saw was one lot of IVI 7.62 that was around 62,000 and the highest 308 was a lot of Winchester Supreme Match at about the same pressure. I tested both lots because there had been complaints about pressure problems. Both were within the allowable limit - but just barely.
You know what, forget it. I am not qualified to provide an answer or really comment, because my lack of experience in this area may just end up freaking people out for nothing. In my defense, the people who posted the information made a very strong case.
I just spent an hour looking through old 7.62/.308 threads here on CGN, I still didn't find the threads I was looking for, I didn't get through half of them, and Ganderite's posts came up more than a few times, with a ton of information that also makes a strong case. So I will leave this to the experts to hash out.
I just spent an hour looking through old 7.62/.308 threads here on CGN, I still didn't find the threads I was looking for, I didn't get through half of them, and Ganderite's posts came up more than a few times, with a ton of information that also makes a strong case. So I will leave this to the experts to hash out.
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canucklehead
CGN Ultra frequent flyer
- Location
- Calgary, AB
It's the Norinco stuff (Peoples Republic of China). I'm pretty sure it's 7.62x51 (if it really matters). The Norinco 5.56 was sold by some retailers as .223, but the spam cans clearly have '5.56mm ball' stamped on the outside.
I bought two crates from Tradex but haven't opened them to verify what's stamped on the cans (if anything).
Either way - if you're shooting it in your 1919A4 - it works fine.
I bought two crates from Tradex but haven't opened them to verify what's stamped on the cans (if anything).
Either way - if you're shooting it in your 1919A4 - it works fine.
