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**Unclenick** · December 29, 2008, 06:27 PM

Danny,

Perhaps by the "other" mainspring, you are referring to the barrel catch spring? It is another "V" flatspring; smaller than the mainspring.

Oh, BTW, plent of loose Goldcups out there. I don't think Colt produced any tight 1911's since the old pre-Sereis '70 National Match guns they fitted by hand. I know I put plenty of time into fitting my own Series '70 Goldcup up.

Jim,

An old timer told me that some of the thicker flat springs will take on a bit of twist if you shave them on just one side. He claimed it unbalanced the stress, and once twisted it was hard to get the opposing side even with the first. He liked slotting or just thinning in the middle for that reason (symmetry) and I've never put his claim to the test. I'm sure it depends on the heat treatment. If the steel is thick enough, I suppose the quench, especially in oil, might not be fast enough to bring the inside up dead hard so you won't get full spring stress through and through? I would think, though, that drawing back in an oven would tend equalize that well enough? He may have had in mind the flintlock springs that were drawn back by setting fire to the oil on them after quenching? Can't say. I'll try it out some time if I get a chance and see?

December 29, 2008, 06:27 PM	#9
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	Danny, Perhaps by the "other" mainspring, you are referring to the barrel catch spring? It is another "V" flatspring; smaller than the mainspring. Oh, BTW, plent of loose Goldcups out there. I don't think Colt produced any tight 1911's since the old pre-Sereis '70 National Match guns they fitted by hand. I know I put plenty of time into fitting my own Series '70 Goldcup up. Jim, An old timer told me that some of the thicker flat springs will take on a bit of twist if you shave them on just one side. He claimed it unbalanced the stress, and once twisted it was hard to get the opposing side even with the first. He liked slotting or just thinning in the middle for that reason (symmetry) and I've never put his claim to the test. I'm sure it depends on the heat treatment. If the steel is thick enough, I suppose the quench, especially in oil, might not be fast enough to bring the inside up dead hard so you won't get full spring stress through and through? I would think, though, that drawing back in an oven would tend equalize that well enough? He may have had in mind the flintlock springs that were drawn back by setting fire to the oil on them after quenching? Can't say. I'll try it out some time if I get a chance and see? __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle Last edited by Unclenick; December 29, 2008 at 06:35 PM.