All this headspace information

[John Sukey (Deceased)]

It would be nice if Clymer provided headspace gages to BRITISH MILITARY SPECS instead of SAMMI specs.

What are the odds that you would find a .303 rifle set up to SAMMI specifications rather than British? How many current sporting rifles are made in .303???????

As far as I am concerned, SAMMI gages are a waste of time in .303 and the person who was thinking 30-40 Krag rim thickness is the same as British .303
must have been smoking funny cigarettes!

Information

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[ireload2]

The .303 British had a long history of evolution in the British military.
It began as a black powder cartridge chambered in a black powder rifle design. Both cartridge and rifle were changed to cross into the smokeless powder era.
Then comes war upon war in which the .303 cal Lee-Enfield was used.
Subsequently the .303 cartridge was changed more than once. It was also used in a variety of machine guns some that were not of British origin.
I have never seen original chamber and head space specifications for the .303 British cartridge or the Lee-Enfield rifle. By original I mean the original engineering drawings for both the black powder and smokeless powder cartridges and chambers. I suspect that over time there were changes in both the cartridge's and chamber's dimensions for the .303 cartridge as used by the British. This probably includes the headspace gauging standards. I have read of some comments that tolerances of British ammunition as well as trench warfare conditions lead to the demise of the Ross rifle and that Ross rifle chambers were then reamed over size in an effort to insure they would function. I have also read that the Ross rifles were considered to be very accurate. To some degree rifle accuracy is known to be related to a precision chamber.

John Sukey's comment brings up a point. What chamber will you get if you purchase on old original British sporting rifle in .303 especially non-Lee-Enfields such as double rifles, those made on Dutch M95 actions and the slant box Mausers?
The round was originally chambered in the US in the 1895 Winchester lever gun. It may have been chambered in other US sporting rifles such a the 1885 Highwall, Remington-Lee rifles and maybe others. In any event the standards in the US would have been established at that time. It seems to be SOP to claim that SAAMI standards are wrong as compared to current British standards. However it is my hypothesis that SAAMI standards are the original standards adopted by the US during original production of the cartridge and chamber combination. The US commerical arms producers had no reason to change their standards to parallel any British changes required by combat experience. Within a few years the .303 chambering was dropped in US commercial rifle production leaving only the production of ammunition in the US. While the SAAMI standards may not match up to Lee-Enfield specifications they may very well match up with the Model 95 Winchester specifications.
So there may be two sets of .303 standards for good reason. In the US we do not have large quantities of British military ammunition or brass. Until recently for decades we only had the brass and ammunition produced by 2 or 3 US commercial producers. Using this brass it takes special attention to detail to reasonable case life when reloading. This is important to anyone that shoots a good bit because 500 cases now cost the same as a decent rifle.
Most of the gauge makers are chamber reamer makers and they make untold variations of wildcat chamber reamers. I am sure that any of the gauge makers will make any head space gauge you require as a special. Just wave money at them.

All of this discussion seems unusual to me. In the collector world there are many that shoot their rifles little or none. I am not sure why they would even participate in such a thread. Those that are shooters but do not reload might have limited interest since they are going to discard their brass. Those that both shoot and reload would have signifcant interest since there is some motivation to insure they are getting the most enjoyment for their $$$.

It would be nice if Clymer provided headspace gages to BRITISH MILITARY SPECS instead of SAMMI specs.

What are the odds that you would find a .303 rifle set up to SAMMI specifications rather than British? How many current sporting rifles are made in .303???????

As far as I am concerned, SAMMI gages are a waste of time in .303 and the person who was thinking 30-40 Krag rim thickness is the same as British .303
must have been smoking funny cigarettes!

[Son]

I suppose the bottom line here is, the SAAMI specs are not applicable to .303 British chambered milsurps for the simple reason they were never taken into account when the specs were done. By default, refer to the British H/S specs of .074" NO GO.
As you suggest, there should be very little concern about any of these sets of data due to the individuals own circumstances, except for re-loaders of commercial brass for milsurp rifles. The idea of having slightly tighter H/S for this situation to increase the lifespan of the brass is a $$$ consideration only and not in any way associated with safety concerns.

Of the several head separations I have seen and asked the shooters about, none could say they realised the case had failed untill they opened the bolt. I carry a ruptured case extractor to the mound, but have never needed it. I have seen one bloke have to use his during a rapid and still got ten shots away (with a compulsory reload) in 70 seconds. It's not the end of the world, just a little delay.

[Edward Horton]

I suppose the bottom line here is, the SAAMI specs are not applicable to .303 British chambered milsurps for the simple reason they were never taken into account when the specs were done. By default, refer to the British H/S specs of .074" NO GO.
As you suggest, there should be very little concern about any of these sets of data due to the individuals own circumstances, except for re-loaders of commercial brass for milsurp rifles. The idea of having slightly tighter H/S for this situation to increase the lifespan of the brass is a $$$ consideration only and not in any way associated with safety concerns.

Of the several head separations I have seen and asked the shooters about, none could say they realised the case had failed untill they opened the bolt. I carry a ruptured case extractor to the mound, but have never needed it. I have seen one bloke have to use his during a rapid and still got ten shots away (with a compulsory reload) in 70 seconds. It's not the end of the world, just a little delay.

Son

The American SAAMI sets standards for civilian commercial ammunition and firearms only and it has NOTHING to do with American military standards or British and Commonwealth military standards. (Note: for some reason the M-14 and the Canadian FN C1A1 (FAL) have the same headspace settings and I think the British L1A1 has different headspace settings?)

My 1943 American Remington made Springfield 03-A3 30-06 ate Winchester cases in its long and fat military chamber like my .303 Enfield does, BUT Winchester cases in my 30-30 and .243 Winchester have NEVER given me any problems what so ever.

Our American SAAMI commercial cases were never designed to shoot in fatter and longer military chambers and this is one of the reasons why some match grade M-14s are rebarreled with SAAMI chambers and set to SAAMI headspace settings.

Below a complete set of American .308/7.62 headspace gauges in .001 increments.




Son, headspace standards are set by whose shoes or boots you are wearing and by what country the shoes and boots are located in.

I don’t wear military combat boots anymore and I have to take orders from the SAAMI on the care and feeding of my brass.



Look at this way Son, what do you think the headspace settings are for the Chinese copy of the American M-14 rifle are, the Chinese do not like the U.S. or the SAAMI. (read below)

http://www.fulton-armory.com/M14S_Eval.htm

[Son]

Our boots may be on different sides of the planet, Mr Horton, but we sing from the same hym sheet.
For interest sake, the H/S gauges for an Aussie L1A1 are 1.6325 inch (accept), 1.638 inch ("soft body reject") and 1.640 inch (reject)