Flat bottom firing spring stop?

[Canoe]

Can someone school me on these?  It seems like a highly recommended part for a 10mm 1911 but I am perplexed by how they work.  My internet search has not been terribly useful.

Also is there a particular brand/model that anyone would recommend?

Interesting that neither my 1911 10mms have one.  Wonder why they would not be a factory part?

thanks folks

[sqlbullet]

It is a flat bottom firing pin stop that you seek.

http://rangehot.com/reduced-radius-firing-pin-stop-1911/

Short version is the flat bottom stop gives the hammer a lot more leverage over the slide.  Makes it harder for the slide to push back my moving the fulcrum of the lever.

It was actually originally spec'd this way by JMB, but it was changed during the 1911A1 revamp to make it easier for GI's to rack the slide when the hammer was down.

[Canoe]

thanks that is very helpful.

[Bat Rastard]

I put a Wilson on my Kimber. It was an improvement, but not a huge one.

[blaster]

wow! I learn something new every day! vey interesting.

[Canoe]

I wonder why these are not stock parts on some of the 1911 10mms, particularly because many 10mm 1911s in stock form seem under-sprung with 16-18# springs and they all fling brass into the next timezone.  I'm comparing to the P220 which is very heavily spring and a beefier design.

Given the range of power available with 10mm ammo, I'm trying to find the right spring/hardware combos to minimize impact on the gun yet maintain proper functioning. I recently put a 22lb recoil spring in one of my longslides and it still functioned very well with basic factory ammo (200gr between 1050-1100 ft/sec) - brass dropped 8' -10' away, no FTF, didn't seem to nose dive too much going back into battery. 

I'll try the flat pin stop and see if it makes a difference.  When I was messing around with my old Coonan, Coonan recommended that I also consider adjusting the mainspring.  Anyway interesting to experiment with these options. 

[spencerhut]

I wonder why these are not stock parts on some of the 1911 10mms, particularly because many 10mm 1911s in stock form seem under-sprung - 16-18# springs and compared to the P220 (very heavily spring), they all fling brass into the next timezone.

People want to pick up a gun at the sales counter and feel how nice and smooth and easy it is to rack.  Going to all the hassle and difficulty of cocking the hammer and then racking the slide on a 1911 is far, far to much work for most people these days.
I end up fitting new FPS on most of my 1911's. Dan Wesson, Ed Brown and Wilson normally have the correct FPS in them from the factory. 
Kimber, Sig, Colt, Rock Island, Springfield . . . just about always need to be replaced.

[Canoe]

I wonder why these are not stock parts on some of the 1911 10mms, particularly because many 10mm 1911s in stock form seem under-sprung - 16-18# springs and compared to the P220 (very heavily spring), they all fling brass into the next timezone.

People want to pick up a gun at the sales counter and feel how nice and smooth and easy it is to rack.  Going to all the hassle and difficulty of cocking the hammer and then racking the slide on a 1911 is far, far to much work for most people these days.
I end up fitting new FPS on most of my 1911's. Dan Wesson, Ed Brown and Wilson normally have the correct FPS in them from the factory. 
Kimber, Sig, Colt, Rock Island, Springfield . . . just about always need to be replaced.

Ya could be.  The guns I have are a Les Baer and a Dan Wesson.   They are radius cut pin stops.  I was reluctant to change them, thinking both set ups would be quite deliberate, but now I think I will give it a shot anyway.

[sqlbullet]

Yeah...Racking the slide is a bunch harder.  Not conducive to novices at a gun counter.

Interestingly, it didn't made nearly as bit a difference on my Witness.  I think because the bottom of the slide is much further from the hammer pivot to begin with.  In the 1911 the bottom of the slide is quite close to the hammer pin.

[The Earl o Sammich]

Heavier recoil spring will hammer your pistol in both directions.  Try a stiffer main spring with that squared firing stop.  Adds to the torque needed at the hammer.

[Canoe]

Heavier recoil spring will hammer your pistol in both directions.  Try a stiffer main spring with that squared firing stop.  Adds to the torque needed at the hammer.

Yes I am going to try the FPS. 

Curious though - how much is a heavier spring really going to hammer the slide in both directions.  It clearly reduces the impact on the frame when fired compared to a lighter spring, but is it really going hammer the slide/frame much more going back into battery - to an extent that may accelerate any wear/damage?  We are talking a difference from 18 to 22#.  I thought the problem with the heavier spring is that it changes the dynamics when shooting (nose dives going back into battery) or leads to more failures to feed if you are not using a good mag spring because because it picks up the round faster. 

[The Earl o Sammich]

You're right.  I miss spoke/typed.  Meant hammer it more going forward.

[sqlbullet]

It clearly reduces the impact on the frame when fired compared to a lighter spring, but is it really going hammer the slide/frame much more going back into battery - to an extent that may accelerate any wear/damage?

The frame and slide parts that get "hammered" as the slide travels to the back are big and beefy and made for it.

Going forward it is the slide stop and two little tiny feet on the barrel lugs.  Which can and do get sheered off in extreme cases:

http://rangehot.com/firing-1911-without-recoil-spring-nothing-broke/

[Canoe]

The frame and slide parts that get "hammered" as the slide travels to the back are big and beefy and made for it.
Going forward it is the slide stop and two little tiny feet on the barrel lugs.  Which can and do get sheered off in extreme cases:
http://rangehot.com/firing-1911-without-recoil-spring-nothing-broke/

Very interesting.  Good info from you and others. 

I'll back off the recoil spring when I change the FPS/mainspring.

[sqlbullet]

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.