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Discussion Starter #1
Want to control your 1911 better for a faster second shot? Go 'Old-School' with it. Change out your Firing pin Stop with that huge radius on it for an EGW flat-bottomed Firing pin stop and file a 1/16th." 45-degree radius on it. Be sure to blend the Radius at the top where it catches the Hammer and drop to a 14lb. Recoil Spring. You'll be surprised at the change in your 1911s' recoil. the 14 pound spring has enough at battery energy left so, don't worry about that.
Oh, after you fit the Stop, if you have one of the newer 1911s with the Swartz-Block firing pin safety(Series 80, II-series Kimber, etc) you have to file/stone the bottom of the EGW stop flush with the slide bottom or it will catch on the Swartz-Block plunger. Then, put the Radius in.

JMB originally designed the stop this way but, the horse-soldiers cried about it being too hard to rack the slide on horsey-back so he changed to the large radius to make the slide easier to rack and to shut them up.

It changes the recoil-impulse to more of a push and the gun comes straight up, not up and to the right like normal with a heavier spring plus, the gun doesn't come up as far.

Try it, you'll like it!
 

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Never heard of this before. Very, very interesting!
 

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Discussion Starter #3
Trust me Snake, it works! Did it to both my Kimber and my Rock Island.
 

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I bet they stole the idea from the USAF !

One of the things we did was radius the firing pin stop so there was a smooth curve from the bottom of the firing pin to blend with the slide.

Actually we made fixtures for that from old, dead slides and just ground them to the desired radius. Then used a belt sander to do the firing pin stop. I've got my old jig somewhere, but it definitely reduced the force needed to rack the slide.

Just do it to the standard firing pin stop... no need to spend extra :wink:
 

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Discussion Starter #5
Charlie, this is just the opposite, with the short radius it's a little harder to rack the slide. I'll get a photo for ya. You'll see what I'm talking about them.

Here's a pic of the one on my Kimber charlie, you can barely see the radius cut at the bottom as it's only about 1/16 to 1/8 " wide and at 45-degrees. I'll take down the firing pin stop tonight and get a clearer photo for you.
 

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Retmsgt.

That is a pretty neat trick. Aside from the 14 pound spring, it may be that the recoil is soften by the 45 degree cut on the firing pin stop causing a different delay in slide motion as it moves over the hammer, which sort of make sense.

I have a pile of EGW and Caspian firing pin stops. I will have to try this. All my guns presently have firing pin stops that are radius and 18 pound springs.
 

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Hey guys, say howdy to my friend Sean.

He's a pretty fair pistol mechanic; hopefully he'll be joining us at Gunstock.

He also is, apparently, pretty handsome - my dog didn't want him to leave last night :)
 

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Discussion Starter #8
Here ya go Charlie, as you can tell, it's an extremely abbreviated radius. Unlike the huge radius you normally see on a firing pin stop. Basically, you are breaking the bottom edge with a 1/16th to 1/8th" wide 45-degree cut that's smoothed on the top for the Hammer to slide easier.

I take no credit for this. This is pure John Moses Browning as he originally intended.



It's Brownells' part number 296-000-058, Series 70, oversized. Cost is a little less than $15.00. BTW, I use it in my Pro Carry II with the Wolff XP recoil spring, it's a 24pounder and this still works! It worked in my RIA with a Wolff 18.5 lb spring but, when I went to the 14lb. spring it was like day and night. Still had reliability too. Fired 100 rounds of Win. White-Box 230 with it without a hitch.
 

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Discussion Starter #9
Oh, one very important thing. Make sure the cut is even all the way across or you'll sideload the hammer and wallow out the pinholes. Sean, you're right, that's alot of what it does.
 

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I still don't understand how going to a lighter recoil spring is going to soften recoil.

The logic behind the mod I described was to reduce the work needed to get the slide going. It was done especially on wadcutter guns
 

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Discussion Starter #11
I think the idea is that you can use a lighter spring, still function reliably and batter the gun less. I know the FPS in conjunction with the spring seems to spread the recoil impulse out. My RIA was coming up about four inches and twisting right. Now, it comes up about 2" and doesn't twist. I get back down quicker with it. And, like I said before, it's more of a shove atrsight back now instead of a jarring kick.

I remember the Wadcutter gun I was issued. If you breathed hard from the bore the slide would start to move. Butter smooth though. God! I wish I could've bought those two guns!
 

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Charlie the concept is reducing the leverage the slide has on the hammer to compress the mainspring. Reduced leverage means more work. More work requires more of the slides energy which uses a downward impulse just as the gun wants to go up. Less energy left in the slide means left energy the shooter has to absorb.
 

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That still seems counter-intuitive.

It makes more sense when you bring the mainspring into the equation and while I don't like reducing the mainspring I have found some real benefit to honing the inside of the mainspring housing and making sure there aren't any rough spots on the spring.
 

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In my experience, you don't need to leave any radius on the square bottom firing pin stop.

I also wonder whether it would be preferable to find a hammer that has the original hole position for the hammer strut pin. Reportedly, this hole was relocated in the Gold Cup, and some aftermarket manufacturers like Wilson followed suit with their custom hammers. The reason for the change in geometry was listed as making it easier to get a light trigger pull, which I interpret as reducing the amount that the strut compresses the mainspring.
 

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Discussion Starter #15
That's why they did it Dan but, I don't think they thought far enough ahead. By moving that strut hole they caused the hammer-strut to rub on the center spring and put pressure on the spring at the disconnector. So now, you have to stone the back of the hammer strut to try and negate it or you'll not get that sweet, light trigger. Which is also why the newer Colt sear-springs have that wierd dish cut between the sear and grip-safety leafs.
 

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I have not really played with recoil spring weight, other than dropping the recoil spring weight until the gun in question will function 100 % of the time with a low power semi-wad cutter loads. As Charlie mentioned doing, I polish all the areas of the frame where the recoil spring might touch. In my own guns, I run a one piece full length guide rod, which I also polish, as well a polishing the outside and inside of the recoil spring. I do notice a smoother recoil pulse with the full length guide rod. Cumulatively, with all of this, the recoil pulse is pretty smooth. Most of my guns have ended up with 18 pound springs, though one that I use for cast loads almost exclusively, has a 16 pound recoil spring.
Walt...the latter gun is the Caspian that has the "light" trigger, which as we discussed, I would NEVER let one go to a client that way, litigation being want it is these days.

That said, I am going to have to try the 45 degree cut on the firing pin stop. I hear tales of folks running 11 pound recoil springs, or even less, even with relatively heavy loads. I would like to see the slide of one of those guns to see how things are holding up to the hammering that I imagine it is taking.
 

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Start out by using just a piece of 800 grit wet or dry to just polish that lower edge. Don't even cut the .45 but just break the edge down. It's all I do.
 

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Discussion Starter #18
Sean, I normally run a 18.5lb. Wolff in Gov't models myself. But, with the RIA, the FPS and 14 lb. spring, the empties collect about three feet away from me and to the side, I tried some mid-range loads my friend made up and they pretty much dribbled out of the port. Now, on my Pro Carry II, the empties pile up about four or five feet away but, I'm running a Wolff 24lb. XP spring in it. It has a FLGR because of the Bull-barrel but in the Rock I'm running a standard Guide-rod,spring and plug. I'm not a big fan of FLGRs, all they've ever done for me is make strip-down interesting.

Not a big fan of light triggers in anything but a Bullseye gun. In my serious guns(Read;carryguns) I like a 4 to 4-1/2lb. pull., crisp with little take-up and no overtravel. If it's set-up right, as you know, it feels like about 3lbs.
 

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I'm lovin' it :!:

I think I'll bring a few 1911s so the wannabes can see how they are supposed to work :wink:

I still don't get all this spring stuff though. The assorted spring weights are a relatively new thing so I can't understand how all the guns we built back then could work so well with the standard spring... and both wadcutter and hardball guns used the same GI spring. 8)
 

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I know that running light recoil springs was popular with some USPSA Limited Division shooters a decade ago. However, I haven't followed the equipment trends for quite a while.
 
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