Flat bottom firing spring stop?

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On the other hand:

https://www.m1911.org/technic1.htm

Bill Wilson says a 24 lb spring is about right for a 10mm shooting full power loads.

But, a flat bottom stop allows you to back that off a good bit. 

Ned Christiansen of Michiguns did some comparative destructive testing using a 45 ACP with factory springs and a shock buff and trying to work up which springs in 10mm would give the same shock buff wear after the same number of rounds.  He landed on a 18.5-19 lb recoil spring, a 25 lb hammer spring (23 is factory) and a flat bottom firing pin stop.

I currently have a 22 lb spring in my Para Ordnance.  But to be honest I don't think the lower lugs are fit quite right and part of that is needed to overcome stem bind that is a bit too much.  The barrel rides the link more than it should.  At 18.5 I get the occasional 3 point jam, but not at 22.  After another 10K rounds or so I will re-barrel and cut the lower lugs a bit better.