1903 Trigger guard screw tap size

[Patrick Chadwick]

Springfield didn't want to pay royalties for patent rights. So they made up their own parts.

OK to make your own parts, but why on earth invent a new thread diameter/pitch combination? Or did they have underemployed toolmakers? In my "It might come in handy one day" draw - well, actually, it's 360 draws in 3 converted office wall cabinets - I have a Chinese-marked 5.5mm die with 0.9mm pitch. One of those things that you just dare not throw away, otherwise Murphy's Law will cut in and ensure that you need it the very next day!

Patrick