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Bill:

I didn't take it that way at all and I hope that you didn't take my response that way.

This issue isn't really confusing at all, as long as you understand what the proof marks were intended to mean. When the proofmasters in Britain and Belgium made the decision to mark BPE rifles as proved for the NfB load, they expected these marks to be understood in the way intended. They've been misunderstood for 115 years. Some victims got away with it. Some didn't.

When the Nitro for Black loadings were being developed in the late 1880s, it was found that a charge of Cordite that produced the same velocity with the same weight lead bullet as the standard black load produced less pressure than black. They also found that such loads usually didn't regulate, so many of the NfB loads used heavier bullets at slightly higher velocity at the same pressure, or less, as the black load.

From the Eley Brothers 1910 catalog:

Absolutely not. The words "distinct" and "only" in the above quote are the crux of the error that many have made because those words underline a distinction that doesn't exist. Black Powder Proof and Nitro for Black Proof ARE THE SAME PROOF STANDARD, and the rifles were proved in the same way. There is no distinction whatsoever between the two. Don't fixate on the propellant used in the cartridges themselves. These NfB rifles were built in the early days of nitro proof. At that time, proof for rifles was based solely on peak operating pressure and peak proof pressure - the only values that could be measured with a base copper crusher pressure gun - not the propellant used to create it. The proof standards for rifles in Britain and (I believe) Belgium in those days were that the proof load had to produce not less than 130%, and not more than 145% of the peak mean operating pressure of the normal load. This remains the proof standard for CIP member states today. Because the nitro propellants available in those days became highly erratic at proof pressures, nitro proof rifles were usually proved with BLACK (indeed, full Nitro Expresses were proved with a fine grain black specially developed for that purpose). What was the peak mean operating pressure of the normal load for a .450 3 1/4" Nitro for Black load? By definition, exactly the same as that of a .450 3 1/4" Black Powder Express - 11 tons. Therefore, under the rules of proof, what was the .450 NfB proof load? You get three guesses and the first two don't count.

(Correct answer: The same one used for the .450 BPE.)

Rifles marked for the Nitro for Black load are not separate or distinct in any way, for any purpose, by any definition, from rifles proved for straight black. "Nitro for Black" rifles, despite the nitro proof marks, are not a separate class from black powder rifles. There were no loads that were appropriate for a Nitro for Black rifle that any black powder rifle was not also considered to be specifically proved for. Whether the cartridge is loaded with black, Cordite, other semi-smokeless, or moonshine, Nitro for Black proof is black powder proof only.

When I said that Nitro for Black cartridges were loaded with lead bullets, perhaps I should have said that they weren't loaded with jacketed bullets. I can find reference to metal based (gas check) lead copper tubed; metal based lead solid; plain lead round nose; paper patched lead copper tubed; plain lead round nose copper tubed; etc. A variety of lead bullets were available. The point was that the portion of the bullet sticking out of the case mouth was lead - the signal that the user could stick it in any rifle that was chambered for that cartridge and in serviceable condition and let 'er bark, with the assurance that all would be right with the world.

The "Light Nitro" name has been loosely used, but correctly applies to those loads between Nitro for Black and "Tropical". True Light Nitro loads were never common and were only available in a few calibers. I can find only one in .450, loaded by Eley; three in .500 3"; two in 500 3 1/4" and one each in .577 2 3/4" and .577 3". Those I gave above came from Flemings "British Sporting Rifle Cartridges". The 80/650 .577 2 3/4" NE load appears to have been loaded only by Eley. These Light Nitros were loaded with jacketed bullets for the same reason that the NfBs were loaded with lead bullets - so that nobody would presume to fire them in a black/NfB rifle. Ah well, no system is perfect.

I believe the "LC" stamp refers to Light Express Cordite, a form of Cordite used by Kynoch in some of their NfB loads. Eley seems to have used Cordite Mk I in theirs.

I hope this helps.
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"Serious rifles have two barrels, everything else just burns gunpowder."

Edited by 400NitroExpress (08/06/06 04:06 PM)