Re: Old Break-Away 6 shot 38cal. pistol
The No. 2 Mk 1 had the hammer spur. The Mk 1* and Mk 1** did not, and many Mk 1 revolvers were converted to Mk 1* by removing the spur. Reportedly the spur was eliminated because the gun was carried by tankers and the spur could catch on interior surfaces or equipment if a tanker had to get out in a hurry.
Since the British considered the revolver very much a secondary and close range weapon, the conversion to what we call "double action only" was not considered a problem.