In reply to:

---

Graeme Wright's recipe book takes the mystery out of shooting them with light nitro

---

Further corroboration of the benign effects of modern Nitro-for-Black (NFB)loads for original Black Powder Express rifles can be found in an article by Sherman Bell in the latest issue of The Double Gun Journal (Spring 2004 issue)

For me, this article has laid to rest some lingering doubts about what pressures might be generated further down the barrel due to different burning rates that aren't shown up by the British Copper Crusher meaurement system, and reported in Graeme Wright's book.

For those that don't get this magazine, Bell used an Oehler Model 43 Personal Ballistics Laboratory to measure pressure curves on a Bolt Action rifle chambered for the 450x31/4" cartridge. Projectiles were 300 gr. cast linotype LFN style ex LBT. The loads tested were;

BPE-120 gr.KIK FFg/Fed.215/1x Fibre Wad. MV=1812 fps

NFB-48 gr.IMR4198/Std rifle primer/OP wad. MV=1952 fps

DUPLEX -9.2 gr SR4759/92.4 gr Goex FFg/2xFibre wads. MV=1656 fps

Pressure was monitored in two places; 1" from the bolt face, and adjacent to the base of the projectile. There was some interesting results from the latter location which speculativley, may be due to the type of wad used for the NFB load, but the general upshot was that the BPE and NFB loads gave identical peak pressures and equal rise times, putting to rest the hoary old notion about black powder being comparatively slower burning and inherently gentler on barrels! And this with an extra 140 fps of MV with the NFB load!!

Also of interest was that, when shot in a gorgeous Alex Henry Black Powder Express rifle, the NFB load produced a 6 shot group of 21/2' at 100 yards, half the size of the BPE load!

Now - if only someone would do some similar work on nitro powders with different burning rates in Full Nitro loads???

Post Extras