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Discussion Starter · #1 · (Edited)
:D So I got to thinking as I was playing around with a P22......hammer hanging in the breech block gap?????? Safety bar cocks the hammer and then the hammer drags along the bottom of the breech block all the way rearward and all the way forward....unless you do the breech block mod. Still, the hammer has to jump over the safety bar, AND, the hammer still needs to ride up on top of the breech block before it gets to the firing pin block.....:cool::cool::cool: Which set me to thinking....why does the safety have to cock the hammer????? Why does the rear of the breech have to cock the hammer??? Why not file off the bottom of the safety bar when it is set to the fire position so that it no longer cocks the hammer or even touches it. In fact why not file off the rear of the breech block so it no longer ramps up to the safety bar and in the process no longer touches the hammer either.

Why not leave cocking of the hammer to the bottom of the breech block, say.....at the area where the roll pin is inserted. Let the hammer ramp up it, be pressed down enough to be cocked, the slide bounce off the takedown lever stop, slide back down the breech block forward to chamber a round. This would cause the only friction area to be overcome when the recoil spring was fully compressed and the rear of the breech and the safety would no longer ever touch the hammer. No more rotating safety, no more hammer tip hanging or bumping over the safety.........

Now things aren't necessarily that simple. We've previously determined that the hammer rebounds appx 0.020" and removing material from under the breech frees it from drag on the hammer....but removing material from the safety bar is another issue altogether. It is the safety after all and a number of safeties on the PK380 have broken. Why????? I don't know, other than too weak. I've never read of a safety breaking on the P22 although the two pistols share the same hammer and hammer spring. The PK380 does have a different firing pin.

Removing material will make the safety weaker for those who drop the hammer on it when dry firing. I don't so I'm not concerned about that. Also, is it possible to remove, say....0.025"/0.030" from the bottom of the bar and have enough material left to block the hammer when the safety is set to safe. Yes, there is enough material. So I took an old breech block, an old safety bar, and old file from the "Make your own extractor from the barrel wrench" thread and had at it. So far so good. This is just an experimental procedure at this point. I have pictures of the process which I will add tomorrow and which is why I didn't finish the sight options.

The weekend is just too short. I'm voting for a 5 day weekend and a 2 day workweek.....who is with me???? M1911


Here is the idea....remove 0.025"/0.030" from a stock breech block and safety bar....area marked in red. The idea is that the hammer would no longer drag on these areas at all.

Here I've set the safety levers to the fire position....the only position I'm concerned with.... and I'm filing off 0.030" of material from the very bottom of the safety bar. I am not removing material from where the hammer is blocked by the safety when rotated to the safe position.


Below is the finished prototype...no need to polish... nothing touches the filed areas. The hammer isn't touching the breech block or the safety bar. Talk about a free slide....yet I've never cracked one. I will get up a photo-shopped picture to show the process. And I need to whack that safety 500 times to see if I can break it due to the removal of material....so don't anyone light into this assuming this is a proven mod. I'm just playing... thing might blow up....:p



Here material has been removed so the hammer no longer drags on the bottom of the breech block as the slide moves forward. Rearward movement was never an issue except with too weak ammo. Forward movement of the slide was where the issue was. Here the safety drum presses the hammer back appx 80% of what is needed for cocking while the bottom of the breech block finishes the job. Once cocked, the slide is free to move forward.
 

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Discussion Starter · #3 ·
Here is a picture of the broken safety that some PK 380s are experiencing. There doesn't seem to be as much metal inside this safety possibly due to the size and location of the firing pin. There have been no accidental discharges due to this to date from what I can read but since the PK380 shares the same hammer and hammer spring with the P22 it sure seems like dry firing either and depending on the safety to stop the hammer might be a bad idea. The mod above will weaken the structural integrity of the P22 safety...will it cause it to crack...don't know. Will the safety still work if it doesn't break....absolutely. No safety features are being deleted. M1911

http://img44.imageshack.us/img44/408/1002221c.jpg
 

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Hi 1911M,

Maybe I'm not quite understanding all of what you said, because it seems to me the hammer will still drag on the bottom of the safety, then the filed down breech block, until it is fully cocked by the unreleaved area above where the roll pin is, each time the slide assy is either pulled back to cock the hammer before shooting the first shot, and every time the slide recoils from a shot to again cock the hammer and seat the next round.

I DO like the concept as the problem with mine is it seems to be "stalling" on its trip back after being cocked, and this mod probably would eliminate contact during that direction of travel.

Maybe I need to "profile" the hammer a bit more as mine still touches the breach block even in the areas I have releived it. I do not have quite as precision equipment as some, but a new caliper will make it much easier to see exactly how much I have relieved it next time I take it appart

I have worked the mod on the breech at least 2 times trying for a longer sloping ramp from the relieved area to the safety pin, but it still seems to "hang" in the slight space between the breech and the safety pin.

Keep us posted though, as this seems to make lots of sense.

Bob
 

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Discussion Starter · #5 ·
Good points Bob......man, you must have a mind like a Steele trap. You are right the safety will be the first item to hit the hammer but higher up which will be an improvement ( I think) havent' tested any of this yet.... There is a slightly redesigned firing pin retainer for 1911s that makes a huge difference in the amount of pressure and smoothness encountered when cycling the slide. You would not think such a small change would have that amount of impact. That is what I'm trying to do here.

The safety will hit the hammer higher....better leverage and the un-relieved portion of the breech will complete the cocking of the hammer. The recoil spring will be fully compressed or at it's highest push point for moving the slide forward. After that the cocked hammer will no longer even touch the rear of the breech or the safety which is where the problem occurs of the hammer catching.

I also want to whack on the safety hundreds of times and fire the pistol a quick 500 times to see if stuff holds up. Just another mod but on I think might improve things and will eliminate removing material from the breech in the vicinity where the retaining pin sits and keep people from removing material adjacent to the firing pin block. In other words....a simpler and stronger mod....if the safety can handle it. More later with some pictures..... M1911
 

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Discussion Starter · #6 ·
Put the pistol back together and there was enough metal left under the original breech mod so that the hammer still cocks when hand cycling. After the hammer is cocked and the slide moves forward about 1/4" there is no drag at all on the hammer. The hammer doesn't cock until the slide has moved all but the last 1/4".

I whacked the safety about 300 times set to safe and 200 set to fire. No damage to anything.

It might be my imagination but I think the safety hitting 0.030" higher up the hammer makes pressing the hammer rearward easier. I might be able to test that with a trigger pull gauge if I can determine that the trigger spring pressure between two pistols requires the same pull to cock the hammer. A new pistol requires 8 lbs of pull on hammer to cock it.

The problem with the safety bar and the gap between it and the breech where the hammer tip could catch was never on the rearward movement of the slide. It was on the rebound when the nose of the breech had to shove a round out of the magazine while the rear of the breech and safety was still dragging over the hammer. This cures that but I still haven't fired it. Will do that tomorrow and report back.

I think I will modify one of the new breech blocks I have and fit it to the pistol and see how that works if everything works out when firing tomorrow. At this point about the only thing slowing the slide down is the recoil spring. M1911
 

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Discussion Starter · #8 · (Edited)
:p Me too......wish I had some sort of machine shop instead of just some old files, a hammer and sandpaper....I could really have some fun. The slide above isn't even fitted on the pistol it came off of but the picture illustrates where I'm going with this....I think. :D M1911



What the original breech block mod looked like...
 

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I think I will order a new breech block, hammer, and safety pin - just in case - and get on tryng this new mod, as I am right now having problems with the hang up when the tip of the hammer drags back over the safety pin / breech area.

From the pic above, I made a gradual sloping ramp all the way from the cut out just behind the roll pin area up to the junction with the safety pin. the first mod looked very much like the picture above, and it seemed to catch on the lip as shown and stop in the small open area between the breech and safety pin. A slight touch with the thumb sent it home, but that is not what I want obviously.

Bob
 

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Discussion Starter · #10 · (Edited)
Bob, S&W sent me a half dozen breech blocks to fool around with. One is for drilling and tapping to mount a small red dot. Did a thread on that. The breech mod above does in fact need the rear ramp to be smoothed up and it was....just not for this picture. There was too much of a sharp ramp there. Later I removed the firing pin block and removed enough material on one breech block so that the hammer never encountered the breech once if slide over the safety bar and rear ramp. But of concern to me was always the removal of material below the area where the roll pin set.

Now I never experienced any problem there but the breech block was surely weakened at that point. It is 0.040" thick stock and I was reducing this thickness by 0.020"/0.025". That left only 0.015" of steel to hold the device in place. Again, I never saw any problems. What I am proposing now is to only have one ramp and to ramp up over the location of the roll pin. This would insure plenty of strength remains there and would not cause any work to be performed near the firing pin block.

What would happen is everything from the roll pin rearward would be lowered 0.025"/0.030" so that the cocked hammer no longer even touches the breech block/safety as the slide moves forward. You must leave the edge of the safety that blocks the hammer untouched. So far I've been unable to damage the safety even with the metal removed as pictured. I really whacked it last night about 500 times dry firing safety on and in the fire position and there were no marks at all and no broken safety. I think the P22 safety has much more metal in it than the PK380.

It might be possible that this mod eliminates re-profiling the hammer altogether. Wish I had a machine shop that could make precise cuts...but a file does a pretty good job. Dremels run too fast and are hard to hold steady. I'd buy a variable speed one next time. All I can say is that so far my slide without the recoil spring in it flops back and forth. No more safety touching the hammer at all. The gap could be 1/4" wide and it wouldn't matter......the hammer doesn't touch it. Picture later. Busy today getting a plan ready. Need some work around here. Things have been very slow for two years. :eek: M1911



The original idea.



Then there was the tiny tapered roller bearing in the end of the hammer......



Then a picture with more explanation.....and one early P22 I had suffered from the safety bar hanging down below the breech block. Never have seen one like it since. Hence the removal of material from the safety in this drawing to make the bar flush wih the bottom of the breech block. This later prooved unnecessary. But now removal of material here is exactly what I'm proposing but not carrying the relief of metal under the breech as far forward. I've got to send this picture to Castor after I autograph it. For some wierd reason he wanted it. Haven't heard from him lately.....must have fallen in the lake his house overlooked.



Then I learned how to Photoshop a bit..... The thickness of the hammer...face to rear needs to remain 0.52" thick or the slide will not press the hammer down enough to cock it. If you are reprofliling the hammer face as shown above....stop there. 0.051" and the slide will not cock the hammer. Of course you need a caliper to measure this closely.

M1911
 

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Discussion Starter · #11 ·
50 RGB and Fed mix went well except for one dud Fed. 10 lb 8 oz avg of 5 to pull the modded slide rearward to cock hammer. 11lb 2 oz avg of five pulls on another smooth shooter with the old breech mod. 1/4 lb difference. Too close to call on whether or not moving the contact point up 0.030" makes any difference. Don't know if the springs match anyway.

I intend to wash all lube off the pistol and fire it entirely dry, not even any moly and see if it works fine with the new mod. So far nothing has broken and the pistol performed 100%. Gotta go. M1911
 

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M1911

Just to be sure that I am reading things correctly I used the pic from above and edited it to make sure I am reading what you are saying. I think this is what you are suggesting:

http://springboro-massage.com/images/breech_mod.jpg

I carefully removed the safety from my gun and cycled it by hand to see where the hammer actually would "catch" and found it was just as expected.

I also realized that I had relieved the block all the way across the pin and not just up to it.

Never no mind, I have not seen any sign of breakage or anything from doing so.

I also ordered a spare breech, safety pin, and hammer assy from S&W (for $50.50) just in case anything I do in experiment form is too much.

Wish me luck.

Bob
 

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Discussion Starter · #13 · (Edited)
You are pretty close. Try this. I can draw better than photoshop but this should show the mod concept. Right now I'm thinking this is the mod I should have thought of originally. It eliminates the hammer from dragging at all on the rear of the breech block and safety and seems to work much better than the other mod and leaves the retaining pin area at full strength.

BTW Bob, I filed my safety while leaving it in the slide, holding the levers in the fire position. The breech block was filed out of the slide with a 1/8" drift inserted through the retaining pin hole. This holds it nicely for filing purposes. Of course wash everything very thoroughly and relube before reassembly. And as I think you've determined you only need to remove material from the safety the width of the hammer, not across the entire safety. I removed material until the hammer no longer touched.....probably closer to .030".....whatever it took.....will measure sometime. M1911





 

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I'm trying to remember, about the original breech block mod.

Wasn't the purpose of the original to prevent the hammer from pushing up on the breech block at the moment when the slide is all the way back... Thus preventing the slide being forced up when only a small section of rails is holding it level, and preventing the rails/slide from wearing down.

I do like the new idea as it cut's down on the friction during the time the slide is stripping and feeding the next round. I guess like everything, it is a compromise...but this appears to be the better option. I can't wait to see more pictures and range reports.
 

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Discussion Starter · #15 ·
I'm trying to remember, about the original breech block mod.

Wasn't the purpose of the original to prevent the hammer from pushing up on the breech block at the moment when the slide is all the way back... Thus preventing the slide being forced up when only a small section of rails is holding it level, and preventing the rails/slide from wearing down.

I do like the new idea as it cut's down on the friction during the time the slide is stripping and feeding the next round. I guess like everything, it is a compromise...but this appears to be the better option. I can't wait to see more pictures and range reports.
You are 100% right Papa...I wouldn't say the purpose was to keep the hammer from lifting the slide when only 1/8" of bearing surface remained but it was a benefit. And, you are right....you can't have it both ways. In fact the hammer moves about 1/2 way onto the firing pin block so in order to really free the slide with the original mod when fully rearward you needed to remove the block and remove enough material along the entire length of the hammer's travel. Some of us did that..:D But with the moly, wear was eliminated in the grooves and rails and hopefully it never returns. I am thinking that if the safety holds up this is a better mod for freeing the slide on its way forward.

Actually a pretty easy mod. M1911
 

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Discussion Starter · #16 · (Edited)


Begin by marking your breech block where you want your ramp to be located. I've chosen to place the ramp over the rear 1/2 of the guide pin hole. I moved forward of these marks as the file bit into the metal. This will minimize the length of drag over the stock breech bottom while leaving the metal over the retaining pin plenty thick.





Here the ramp has been filed that will guide the hammer up and onto the borrom rail which will cock it. 0.030" of material has been removed from the rear of the breech by use of a small triangular file. The stock breech is 0.270" thick at the rear work area, the cut for the firing pin is 0.087" deep which leaves a solid metal thickness of 0.183"....I'm filing off 0.030" which could have been less but that leaves 0.158" of solid steel at the rear of the breech. Over 1/8". May not sound like much but these parts are pretty small to begin with.



Here the breech block has been loosely fitted into the pistol. Nothing has been polished at this point. Earlier I had filed the safety bar along with an old already old style modded breech and it still worked fine but I had some new breech blocks and I wanted to file these properly for this mod. The previous safety still looked good so I stuck with it rather than file into another one until I find out if the safety will break or have other problems. Notice that I did not file into the area where the safety rotates. I filed it while in the pistol. Then cleaned it really well. Removed it and cleaned it some morebefore reinstalling in a second pistol. I calipered both and nothing has changed over the years.



Pictured is the slide installed with the hammer just being cocked by the material left over the guide pin hole. The hammer will drag over appx. 1/4" of breech block rail. This is necessary to cock the hammer.



Pictured is the hammer under the re-profiled safety. You can see the gap at the left of the hammer. I actually have more gap than is necessary but that is because I filed the safety for one pistol and the hammer that was on it and then swapped the part to another pistol. The fit would be better if I weren't swapping parts around and I will save this safety to go back on the other firearm when I am sure this mod works as well as I think it will and if the safety doesn't break.



Here I have rotated the safety to the safe position. You can see where the hammer is dragging on rearward movement to cock the hammer. This has never been where the P22 has a problem but I will need to polish things up a bit.....just because. Looks like I got it pretty square anyway....I guess I pass filing 101 The little ramp actually helps forward movement of the slide as the spring loaded hammer slides down it.



Here is a view of the area of the safety that stops the hammer. I've left as much as the hammer hits anyway and have never seen any peening to the hammer or the safety now or on previous pistols. 500 + tests of this filed down safety have been conducted by dropping the hammer on the modded safety. This safety came off a pistol with appx. 15,000 previous impacts, from firing, that is.....I don't routinely drop my hammer on anything but a chambered round. So far the safety looks fine but I've only fired it about 50 times so I need to run 500 or so through it to test everything. I cannot believe how smooth the slide cycles when the hammer doesn't have to bump over the safety. On the other hand, with the safety set to safe....the jump is even more than before because of the lowered breech so it is more of a jump for the hammer if you are hand cycling with the safety set to safe. Works fine but the roughness of the jump is a little worse than a stock set-up. It's reliability during firing that I'm concerned with not hand cycling that first round. If I want that first round to be smooth.....I can simply cock the hammer first. This is probably the mod I should have come up with originally. M1911
 

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Just came in from test fireing the gun with the above mods. I fired 50 rounds and all cycled the slide just great. Like M1911 I didn't even lube it, just cleaned carefully after the fileing and re assembeled.

Unfortunately when I had done the first mod I releaved a little bit farthur back than I should have, so there were about 2 shots that it didn't fully cock the hammer. It fired DA instead of SA so no real problems even with that

That will be remedied when I get the new breech to "carve" on. I will have it relieved just about like in the first picture as above, short of the roll pin.

In the first mod, in order to give it as much clearance as possible, I relieved back to above the pin almost where the dip goes pack down towards the safety oval hole. I did it that way as I was depending on the safety rod to cock the hammer and didn't want any inteferance behind that if possible.

The new one to come will not be relieved that far back.

Now I will get busy checking out ideas for the other "slide cushion" mod that is also being talked about. When parts come I can get back to this again.

Thanks for your great ideas M1911.

Bob
 

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Discussion Starter · #18 ·
Yep I did the same thing on several breech mods and removed the firing pin block to make sure the hammer didn't hit it. In fact I relieved the entire bottom of one breech block with a smooth ramp only at the front edge left it thick enough to pick up a round from the magazine. And if you mod one of those....there is nothing left to cock the hammer. My first effort at this worked because I had left just enough material adjacent to the firing pin block hole. The hammer travel appx. to the center of the firing pin oval. I've go two more pistols that are going to need the new breech mod so I'd better be calling S&W tomorrow and ask for a couple or do I still have enough.....will have to check. :) M1911
 

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Discussion Starter · #19 ·
I added a profile picture of the rough filed shape.....this should clarify what is going on from the side perspective. Plenty of metal over the retaining pin hole and the ramp helps the slide move forward as the spring loaded hammer slides rearward off of it. M1911

 

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Thats funny 1911M, I did that after looking at your bible with the original mod. I thought the safety bar would work better in the fire pos. if it were flat like the block. It works great and doesn't hang up anymore like it did before any mods.
 
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