Headspacing belted magnums

[bigedp51]

Tbob

From the SAAMI.org
Glossary
Headspace

1. The distance from the face of the closed breech of a firearm to the surface in the chamber on which the cartridge case seats.

SAAMI headspace for the 30-06 rifle
2.0487 GO
2.0587 NO-GO

Forster 30-06 gauges
2.049 GO
2.055 NO-GO
2.058 FIELD

And the US military measures 30-06 headspace from a different point or datum line.

Headspace for the M1 military rifle
1.942 GO
1.944 NO-GO
1.950 FIELD

http://i122.photobucket.com/albums/o254/bigedp51/headspacemil.jpg

It would appear that nothing is written in stone.

I have seen it written as head clearance and head gap clearance and both are the airspace between the bolt face and the rear of the case.....................

Most of these rifles below are now gone and I now have new rifles with tight headspace, very little airspace and I don't use a case to set my headspace. ;D

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6390.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6475.jpg

I now rest my case. ::)

[Con]

bigedp51,
Thanks for those images of 303 chambers ... your posts are always highly educational. The O-ring suggestion to get a 303Brit shooting without excessive case stretch is a beauty and much simpler than necking up to create a false shoulder and then fireforming. ;)

Where did the brass endurance test table come from? I wouldn't mind reading more about what was done there.

Thanks again.
Cheers...
Con

[bigedp51]

Con

Case quality varies and even more with American made cartridge cases and this is why competitive shooters use Lapua brass made in Finland.

I will say this to all of you, the Army Lake City Army Ammunition plant no longer has Remington or Winchester manufacturing ammunition there. In 2001 Winchester lost the contract at Lake City to produce ammunition for the government. In 2007 Winchester sold its brass division and no longer manufactures its own brass for ammunition.

The world is a changin"

And Blount International is the largest producer of ammunition in the US. (ATK, CCI, Speer)

•2000
Selected to operate Lake City Army Ammunition Plant, the U.S. Government's only small-caliber ammunition manufacturing facility.
•2001
Acquired the commercial ammunition businesses of Blount International, which made ATK the nation's largest manufacturer of ammunition.


So when it comes to choosing cartridge cases your going to have to pick your own poison.

[L.F.Combs]

This is an interesting thread.... wish I had been here from the start. Headspace is something I always like to hear people talk about on cartridges. It is always interesting to see how others explain headspace..

[sha-ul]

bigedp51,
Thanks for those images of 303 chambers ... your posts are always highly educational. The O-ring suggestion to get a 303Brit shooting without excessive case stretch is a beauty and much simpler than necking up to create a false shoulder and then fireforming. ;)

Where did the brass endurance test table come from? I wouldn't mind reading more about what was done there.

Thanks again.
Cheers...
Con

Ditto, his post are indeed good stuff. ;)