Military ammo in new 10FP
- Thread starter smoktire
- Start date
maple_leaf_eh said:
5.56 NATO develops much higher chamber pressure than .223. To use this round is potentially dangerous in a non-5.56 rifle.
I'm sure that people will chime in with stories of firing 5.56 out of a .223 barrel and having no problems whatsoever, and I'm sure that this is true the majority of the time, however, repeat that often enough and you just might find out why their is a warning in the first place.
ETA: The casing of 5.56 is not to SAAMI spec. I'm no expert on the subject, but I believe that the shoulder is further forward than on .223.
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Leg said:
.223Rem Chambers are a wee bit tighter then 5.56 chambers.
.223Rem can be shot in 5.56 chambered guns, but 5.56 ammo SHOULD NOT be fired in .223Rem Chambered guns.
The same goes for .308Win & 7.62...................
AS mentioned in the post above the 5.56 & 7.62 chamber pressures are higher then their civilian counterparts.
SKBY.
7.62 vs .308
From wikipedia:
"NATO 7.62x51mm cartridge is nearly identical to the commercial .308 Winchester. NATO controls specifications for the military round while SAAMI controls specifications for the civilian round. The organizations have established two differences: the standard pressure is 50,000 psi, as measured by the copper crusher gauge, for most military rounds, while the SAAMI maximum is 62,000 psi, measured with a piezoelectric gauge, for the civilian round. Since the two types of gauges give different pressure readings, the two pressures cannot be accurately compared. The NATO M60 High Pressure Test round is loaded to a pressure of 67,500 psi, so military arms should be capable of handling the pressure of civilian rounds. The military chamber is specified to be 1.645 inches, compared to the civilian chamber of 1.632 inches. Though this difference is just 0.013 inches, a chamber of acceptable military length will put excessive stress on the thinner civilian brass, causing premature head separation. While it is safe to mix .308 and 7.62x51mm ammunition, problems will not be encountered if the correct caliber designation is used."
So .308 is certainly okay in a mil spec gun, but not necessarily the other way around.
From wikipedia:
"NATO 7.62x51mm cartridge is nearly identical to the commercial .308 Winchester. NATO controls specifications for the military round while SAAMI controls specifications for the civilian round. The organizations have established two differences: the standard pressure is 50,000 psi, as measured by the copper crusher gauge, for most military rounds, while the SAAMI maximum is 62,000 psi, measured with a piezoelectric gauge, for the civilian round. Since the two types of gauges give different pressure readings, the two pressures cannot be accurately compared. The NATO M60 High Pressure Test round is loaded to a pressure of 67,500 psi, so military arms should be capable of handling the pressure of civilian rounds. The military chamber is specified to be 1.645 inches, compared to the civilian chamber of 1.632 inches. Though this difference is just 0.013 inches, a chamber of acceptable military length will put excessive stress on the thinner civilian brass, causing premature head separation. While it is safe to mix .308 and 7.62x51mm ammunition, problems will not be encountered if the correct caliber designation is used."
So .308 is certainly okay in a mil spec gun, but not necessarily the other way around.
Big JD-From the hills
CGN Ultra frequent flyer
- Location
- Saskatchewan.
I would say its ok to put the lower preasure 7.62 round in the tighter/higher preasure .308 chamber and not the other way around(as long as the bullets are not jambing into the lands)!?
.223/5.56 is a totaly different bag of worms...
.223/5.56 is a totaly different bag of worms...
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pilgrim said:
Personally I wouldn't. That 7.62 NATO ammo is loaded to higher pressure then commercial ammo. Plus 7.62 NATO ammo is spec'd for a slightly longer chamber.Commerical chambers are a wee bit shorter.
SKBY.
OK, I have said this about a hundred times
When DA and IVI ammo was issed for competition to the DCRA and PRA's rifles chambered in .308 and .223 were used. Hundreds of thousands of round of 7.62 and 5.56 were fired through .308 and .223 chambers. If it was making civilian rifles go kaboom, do you think the DND would have issued it for civilian use on DND ranges
Over in the UK ammo is still issued for competition. This ammo until a few years ago was RG 144 gr ball ammo in 7.62. It has now changed the RG 155 gr ammo. Made on the same machine as regular old ball ammo at Radway Green that is the MoD supplier.
Again, hundreds of thousands of rounds of 7.62 every year fired out of .308 chambered rifles.
Any factory rifle can have a tight or loose chamber, some will fire 7.62 or 5.56without a problem. While others may be on the low end of the tolerence and have problems shooting factory ammo.
When DA and IVI ammo was issed for competition to the DCRA and PRA's rifles chambered in .308 and .223 were used. Hundreds of thousands of round of 7.62 and 5.56 were fired through .308 and .223 chambers. If it was making civilian rifles go kaboom, do you think the DND would have issued it for civilian use on DND ranges
Over in the UK ammo is still issued for competition. This ammo until a few years ago was RG 144 gr ball ammo in 7.62. It has now changed the RG 155 gr ammo. Made on the same machine as regular old ball ammo at Radway Green that is the MoD supplier.
Again, hundreds of thousands of rounds of 7.62 every year fired out of .308 chambered rifles.
Any factory rifle can have a tight or loose chamber, some will fire 7.62 or 5.56without a problem. While others may be on the low end of the tolerence and have problems shooting factory ammo.
Maynard,
I echo your sentiments....101 %
This comes up like clockwork....Though the purists will argue till the cows come home the insidious dangers of mixing and matching 223/556 762/308, much akin to 87 octane from esso and 87 octane from chevron...I have mixed and matched for many moons out of my mini 14 , AR15A2 700P in 223 and 762 with NARY a problem....Nary.....Though everyone will argue Im only tempting fate
I echo your sentiments....101 %
This comes up like clockwork....Though the purists will argue till the cows come home the insidious dangers of mixing and matching 223/556 762/308, much akin to 87 octane from esso and 87 octane from chevron...I have mixed and matched for many moons out of my mini 14 , AR15A2 700P in 223 and 762 with NARY a problem....Nary.....Though everyone will argue Im only tempting fate
jennis said:
And so are the hundreds of shooters at Bisley every year. Hell they even allow cadets to shoot 7.62NATO in .308 chambered rifles. In fact, RG 7.62NATO with the 155 bullet is the only ammo authorized for the Canadian cadet RPA target rifles. Would the DND put young cadets at risk of injury or death if this was unsafe?
All I will say is that manufacturers have disclaimers/warning against shooting Mil Spec 5.56/7.62 ammo in .223Rem/.308Win chambered rifles.
Whether you do so is at your own risk.
The choice is ultimately up to the shooter.
SKBY.
Whether you do so is at your own risk.
The choice is ultimately up to the shooter.
SKBY.
Parker-Hale Mike
CGN Regular
- Location
- Beautiful Victoria
The DCRA 7.62 No4 mk1 enfields should be proof enough that it is not a risk to use 7.62x51 in exchange for .308 in modern rifles. If something was going to let loose from overpressure, I am positive that it would happen in a rear locking lug enfield.
