W W Greener reported on the practice (& thoroughly condemned it I might add) of some early work of breech loaders of cutting the chambers with a step at end rather than a cone. This seemed to offer no practical advantage, was impossible to exactly fit shells of all makes as lengths had some variation & left a sharp corner, hard to keep sufficiently clean, leading to the possibility of corrosion weakening.
"ALL" guns should have their bores & chambers examined prior to ever placing a shell in the chamber & the older it is the more important this is. With all due respect to Mr Fergus (I have read his account of this also) to have ever fired that first shell in which the mouth of the case would actually open into the "Bore" itself was nothing short of Utter Foolishness. That stepped or Extremely short angled cone should have been well noted & "NO" shell fired in that gun of which its fired length exceeded the chamber length.
When the British began loading fold crimp shells in the late thirties they feared the shorter overall length might lead to some of them being mistaken for 2" shells & thus placed in the wrong guns. They thus carried out "Extensive" testing of lengthening the hulls to the point they would have about the same "Loaded" length as the roll crimp hulls of the nominal 2˝" variety. They found this to be a totally acceptable practise * was adopted for I believe all nominal 2˝" British shells from that point on. While Mr Bell's tests gave similar results, he really had no need tom "Find out for Himself" as it had been standard practice for 60-70 years.
I seriously question whether his tests were extensive enough to truly determine a pattern & just how much of his pressure variations were simply normal variations found in testing even a single lot of shells, all loaded "Just Alike".
