Chicagoland MG Club: Driveline February 2014

books The Library Muse

I was reading a history on the civil war the other day and came across the term Whitworth rifle. Got me to wondering if there was any relationship to Sir Joseph Whitworth (1803-1887), the English engineer. The name should be familiar to any British car or bike owner, especially those with T-Types. In 1841 he developed BS. No, not that. It stands for British Standard, also known as British Standard Whitworth, BSW. The system standardized screw threads with an angle of 55 degrees and a standard pitch. It was adopted first by the railroads, which up to that point had all used different threading systems, then the rest of the manufacturers. Morris and MG engines from 1923 to 1955 were built using metric threads but with bolt heads and nuts in BS, supposedly because the engines were produced using machine tools previously owned by a French company. As a teen I owned a 1956 Austin Healey 100-4. I had to go to Sears to get a 3/8 Whitworth socket for the head stud nuts, every other nut as I recall was SAE. 40+ years later I still have that socket. I have no idea what the threads were.

But I digress. Yes indeed the rifle was developed by the same man. At the beginning of the American civil war the ‘modern’ long gun was the percussion (cap and ball) Minie ball rifle, the bullet of which was neither miny (.58 caliber, 500 gr) nor a ball (conical). It was named after its developer, Minie. Again with the French. Here’s some information you can bore your family and friends with. The rifle had a rate of twist of about 1 in 78. That means that the bullet travels 78 inches to complete a 360 degree spin. The spin (rifling) makes the bullet travel on a truer path, much as a quarterback will put spin on a football when he throws a spiral pass. Whitworth increased the rate of twist to 1 in 20 and decreased the diameter to .451. This increased the maximum effective range of the rifle from 150yds to 500yds. The sniper version with telescopic sights could go out to 1300 yds. This trend continued. The modern army’s M16 started with a rate of twist of 1 in 14, then 1 in 12, and currently is 1 in 7, with a .223 caliber 55 gr bullet.

The English, who I think were still POed at the north about 1776 and 1812, supplied the southern forces with some of these Whitworth Sharpshooters. But none to the north. Maj. General John Sedgwick was the highest ranking northern officer killed in action. At the battle of Spotsylvania Courthouse his unit was taking fire from some southern snipers using Whitworths. His men were taking cover while he remained on horseback. Just seconds before he fell from his horse with a fatal shot in the left eye he was quoted as saying “I’m ashamed of you, dodging that way. They couldn’t hit an elephant at this range.” And that’s no BS.

~~Bill Mennell

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