From: "[EMAIL PROTECTED]"
the 308 Winchester, AKA, 7.62 NATO.
Ed Crook's input was very informative but is the above totally accurate?
Aren't the 308 Winchester and 7.62 NATO interchangeable rather than
synonyms for the same cartridge? Apart from the NATO cartridges tending to
have thicker case walls and thus a lower internal capacity I thought there
were minor dimensional differences as well.
In halcyon days gone by I remember one guy who got very upset by the fact
that his BAR would shoot 308 with total reliability but would often misfire
with 7.62 NATO. The reason being that the NATO case was very slightly
shorter up to the shoulder, the case sank into the chamber further and the
firing pin didn't always reach far enough forward to strike the primer as
hard as necessary to cause detonation. A harder military primer may also
have contributed to his problems. Hunting bolt action rifles don't seem to
suffer from this but the semi-auto was more sensitive. I also seem to
recall that the commercial cartridge is loaded to somewhat higher pressures
and very tightly chambered target rifles in 7.62 won't always chamber 308.
Can anyone comment?
Kenneth Pantling
--
There are different chamber reamers for "match" .308 chambers but
in reality commercial .308 cases and 7.62 NATO cases that I
have examined appear identical from the same manufacturer.
I know they had problems at Bisley when they issued INDEP
7.62 sniper ammo which is accurately pretty accurate but
not in a TR with a match .308 chamber.
The same is true for .223 and 5.56. Some countries have a
spec for their 5.56 ammo which deviates from .223. However
usually, for example, Winchester .223 brass is identical to
their 5.56mm brass.
I even got some Swiss Ammunition Enterprises 69gr HPBT and
that stuff has the exact same case as 5.6mm Swiss, but is
headstamped ".223"
The other thing to remember is the SAAMI spec in the US
which sometimes takes no account of the military spec,
9mm Para is a good example. The SAAMI spec says that
9mm NATO loadings are overpressure, which is ridiculous.
So you have Winchester turning out silly things like
"+P+" JHPs which are simply ordinary JHP bullets loaded
to the NATO spec.
Steve.
Cybershooters website: http://www.cybershooters.org
List admin: [EMAIL PROTECTED]
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