M1A Scout

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Dojeda

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Hey guys i'm brand new to this forum. Can anyone help me out with the chambering of an M1A and M1A Scout? I've contacted SA and obviously tech guys who don't actually build the rifles don't know.

Are they chambered in 7.62mm or .308? Thanks
 
This is true however the 7.62 and the 5.56 being mil spec rounds have much higher chamber pressures than their civilian equivalents therefore it's not a good idea to fire the mil spec rounds through the civilian chambers.
 
I've read and understand the physical and pressure differences between the 5.56 and .223 cartridges, but do they apply to 7.62/.308? I would assume the pressure of a 7.62 would be higher but what about the dimensions?
 
This is true however the 7.62 and the 5.56 being mil spec rounds have much higher chamber pressures than their civilian equivalents therefore it's not a good idea to fire the mil spec rounds through the civilian chambers.

Not true in the case of the 7.62 Nato vs. .308 Winchester. The last time I checked the specs, I believe the military load had maximum pressure at approx. 50,000 PSI whereas the SAAMI spec for .308 Win had a max. pressure of 62,000 PSI.

Springfield M1As are headspaced to safely fire either round.
 
We need a sticky for this.

5.56 in a .223 chamber IS a safety and pressure issue.

HOWEVER, 7.62 NATO in a .308 chamber is neither a safety nor a pressure issue. 7.62x51 and .308 Win are interchangeable for 99.9% of civilian purposes, which is not true of 5.56 NATO and .223 Rem.
 
HOWEVER, 7.62 NATO in a .308 chamber is neither a safety nor a pressure issue.

Such an assertion would be based on an assumption that the Army's Technical Manual of Ammo Data Sheets (TM 43-000 l-27) incorrectly states the pressure in PSI rather than CUP. We do know for sure that the SAAMI spec for max chamber pressure in .308 Win is 62k PSI, which is a bit different.
 
The Springfield Armory M1A is chambered to a 1.630 to 1.631 headspace dimension.

I used a Forster 1.630 headspace gage to calibrate my RCBS headspace gage.

I measured several types of milsurp and match-grade ammo.
Only the Malaysian belted 7.62 ammo exceeded 1.630.

015-comparisonchart-1.jpg
 
The argument of "what is the difference" between .308 Winchester and 7.62 NATO has been done to death on the gun boards.

See Google

There are the following camps:
  • They are the same
  • They are different
  • They are the same, but measured different
  • They are different, but the differences are too small to matter
  • They are different, and the guns for each are different
  • They are different, but the differences in the guns are too small to matter
  • The dimensions are different, but the pressures are the same
  • The dimensions are the same, but the guns that use them are different

It goes on ad nauseum.

If it says .308 Winchester or 7.62 NATO it will PROBABLY function fine in any gun marked as either.
I have NEVER heard of a gun "blowing up" - or even being damaged - because one or the other such-marked cartridge was used in any particular gun.

Some people have had problems with .308 Winchester in Century CETME guns.
Rims get ripped.

The beavers are the same, but they are different...

There is no end to it.
 
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