Ishapore 2A1 headspace gauge/ Measurement

[boostedawd91]

Yea it was a mistake by me, what i thought to be 7.62 nato ammo actually turned out to be 308 ammo which it doesn't like shooting so I just picked up some good 7.62 nato ammo im gonna shoot today and see if there is any issues with it or not.

[Alan de Enfield]

As a rule of thumb Military ammunition seems to have about a 10% less capacity that civilain ammunition - as the outside dimensions are the same this can only mean that the Military stuff has thicker walls and is therefore stronger.

Click the link for some interesting info - make your own mind up.

7.62x51mm NATO or 308 Winchester? What's the Difference?

[boostedawd91]

Yea, military cases usually have thicker cases. I shot some i believe its m80 lake city arsenal 7.62 nato ammo today and it does seem to be bulging the cases. They are about .006-.010 thicker towards the bottom after being fired than the unfired cases. Is that a big issue?

[Parashooter]

They are about .006-.010 thicker towards the bottom after being fired than the unfired cases. Is that a big issue?

No. It's perfectly normal - and entirely within the deformation limits of decent brass. Even with the fairly tight SAAMI specs for US sporting arms, there's .011" difference between the minimum cartridge base diameter and the maximum chamber diameter.


Note tolerances of plus .002" on chamber diameter and minus .008" on cartridge body diameter.

[boostedawd91]

Im probably not gonna be able to reload those cases that have expanded correct? If i shoot again they will probably expand more than the case can handle

[Parashooter]

No, they should be fine for reloading. Again, .010" expansion forward of the solid base portion is within the normal range and nothing to worry about.

[boostedawd91]

Well i sent the gun down to brian at BDL limited, a enfield specialist, to have it checked out and a new bolt head fitted to tighten up the headspace. He just got back to me confirming that its way out of spec so once i get it back, ill let ya know how it shoots. Before my groups were getting worse everytime i shot it so looking forward to see how it does once it's nice and tight

[pcaru1]

The official paperwork has already gone in via the Military system to the Indian REME at wherever it is in India. In our own system you can just phone someone you know - it's called back scratching. But you just can'tdo this into anotherArmy.

As soon as it comes back I'll tell all

I don't suppose they responded yet?

[jmoore]

SAAMI specs for US sporting arms, there's .011" difference between the minimum cartridge base diameter and the maximum chamber diameter.

Looks like a 0.0011" rather than a 0.011" difference at the 0.200" datum plane.

But otherwise, the 0.006"- 0.010" radial expansion is nothing to worry about. There's an old thread that tests the outer limits of the safe radial expansion near the base.

---------- Post added at 12:43 AM ---------- Previous post was at 12:42 AM ----------

I don't suppose they responded yet?

Yes, yes they did. Page back a bit.

[pcaru1]

Someone's just asked me how come I'm so sure about the Indian rifle CHS spec. I have to say that I'm NOT sure. It's just that I question why every other bolt asction 7.62mm Enfield is between these two specs, why wouldn't the Indian rifle be the same.

I'll tell you all what I'll do first thing next week. I'll make a written request to the Indian Army Liaison Officer to see if he can find out for us. Wait out!

jmoore- This is what I was questioning about a response. It's been a while. Just wondering what the ILO will come up with.