Tweaking The Sear Spring On The 1911

["DoubleAction"]

This is the Sear Spring as it engages the Disconnector and Sear. Notice the contact of the # 1 leg to the Sear. Also; Notice the Center Leg of the Sear Spring as it contacts the Disconnector and presses upward against the plate, in order to push the disconnector up into the recess of the center rail, while allowing the plate to drop back down. The Center leg of the spring works with the Disconnector in a wedge like manner. The # 2 arrow is pointing to the right leg of the spring, which provides tension for the grip safety.

One easy way to tune the Sear Spring for me, is to take one of my Wilson Combat pistols and use its Sear Spring has a guide ;D ;D

[TMan]

One easy way to tune the Sear Spring for me, is to take one of my Wilson Combat pistols and use its Sear Spring has a guide

I'm not sure that I understand this. Are you using it with a tension gauge or are you comparing the amount of bend?

["DoubleAction"]

TMan : "I'm not sure that I understand this. Are you using it with a tension gauge or are you comparing the amount of bend? "

I compare the amount of the bend. This has worked for me on three pistols and my brother compared to triggers on my Colts to that of my Wilsons and he could not tell the difference.

[TMan]

Well, when I read it, I thought that was what you meant, but then I got thinking about the fact that unless you were using springs made out of exactly the same material there could be a difference in spring tension even though the shape was the same.

I guess it isn't enough that it is noticable.

["DoubleAction"]

TMan; Using the Wilsons as a guide, only puts me in the ball park, but maybe only one or two tweaks will do the job.

[TMan]

Apr 29, 2010 9:19:58 GMT -5 "DoubleAction" said:

TMan; Using the Wilsons as a guide, only puts me in the ball park, but maybe only one or two tweaks will do the job.

OK, that makes sense and is probably a real time-saver.

["DoubleAction"]

"OK, that makes sense and is probably a real time-saver."

TMan; You are right.

[TA]

It's been a long time since I tweaked one, but I remember there is a way to use a trigger pull guage to check tension on the sear and disconnector legs seperately. There is/was a guide on Brownells on how to build a 2.5 lbs. trigger pull. Especially at the extremely light triggers like that, the spring needs to be balanced properly to prevent follow. I was able to achieve the 2.5 lbs, but I did start to get some follow, so I bumped it up to 4 lb which fixed it. This was on an older Kimber. It was a fun project which I don't have much time to do these days.

[TMan]

TA, I've gone the Brownell's 2.5lb trigger route on a Springfield 1911 in 9mm. As I recall, it was around 5lbs from the factory with a crisp trigger. I was fine with it, but when Becky shot it, she showed me the indentations on her finger and told me I needed to fix the trigger.

I think DA's approach is excellent. Suppose you aways buy springs from a particular distributor - say 'X'. You work at it and adjust and adjust and get it perfect. Then you remove that spring and use it as a template for bending the springs on your remaining 18 1911's all using a new spring you bought from 'X'. It is like using a laser to bore sight a scope - it will get you close.

["DoubleAction"]

I have few Sear Springs that has already been tweaked, as guides. I read Jack Weigand's article on Brownell's Bench Talk, about the 2 1/2 lb. trigger pull. I have much easier ways to get around that, while using top of the line trigger components.

I always remove my grip safety while I do the tweaking. If I have any tweaking to be done, I do a trigger pull test, remove the Main Spring Housing, and go from there.

[TMan]

Perhaps this should be another thread, but since it is the same physical spring...

Another thing that effects the trigger pull is the weight of the hammer spring i.e. the force that the spring has on the hammer. I've always assumed that making it lighter makes the trigger pull easier, and as long as I don't get light primer strikes I'm okay.

However, is that true? During ignition and the traveling of the bullet down the barrel. During this period of time, the slide is locked and there are 3 forces keeping it that way: 1) the friction of the bullet against the barrel, 2) the tension of the recoil spring, 3) the tension of the mainspring against the hammer.

Is it possible that by reducing the tension on the mainspring that the slide could start moving too early and effect accuracy?

["DoubleAction"]

TMan : "Another thing that effects the trigger pull is the weight of the hammer spring "

TMan; The Mainspring (Hammer Spring ) is what I always replaced with a lighter spring, prior to tweaking the Sear Spring.

["DoubleAction"]

TMan : "Is it possible that by reducing the tension on the mainspring that the slide could start moving too early and effect accuracy?"

TMan; The 1911 pistol is designed so that the recoil don't begin until the bullet exits the barrel.

[TMan]

May 1, 2010 18:52:32 GMT -5 "DoubleAction" said:

TMan : "Is it possible that by reducing the tension on the mainspring that the slide could start moving too early and effect accuracy?"

TMan; The 1911 pistol is designed so that the recoil don't begin until the bullet exits the barrel.

"designed..." Okay, but what are the attributes of that design that ascertain that the recoil doesn't begin until the bullet exits the barrel. It ain't magic. ;D

["DoubleAction"]

TMan : "Is it possible that by reducing the tension on the mainspring that the slide could start moving too early and effect accuracy?"

"designed..."
"Okay, but what are the attributes of that design that ascertain that the recoil doesn't begin until the bullet exits the barrel. It ain't magic"

If I said that is depend on the recoil spring, I would be wrong, because I have seen pistols in high speed slow motion, without the benefit recoil springs, prove that slide don't recoil until after that bullet leaves the muzzle.

Its magic is found in the locking mechanism of the pistol, aka Locking Lugs, which pistol remains locked in battery, until the bullet exits the muzzle.

[TMan]

Its magic is found in the locking mechanism of the pistol, aka Locking Lugs, which pistol remains locked in battery, until the bullet exits the muzzle.

Hmmm, the locking lugs lock the slide to the barrel, not the slide to the frame. (Fantastic picture by the way). If I go get a 1911 right now, the pistol is locked up, but I'm able to move the slide backwards, it remains locked until a certain point where the downward movement of the barrel releases the slide for it to continue on its way.

I understand something like an AK47 or AR15 where there is a hole in the barrel and the pressure isn't there until the bullet has passed. That is easy.

We have discussed this before, but is still isn't clear in my mind - perhaps because I'm just getting old.

The Hi-Point 9mm has this massive slide because of being a blow-back design. They say that the mass is necessary to keep the slide from moving backwards until the bullet has left the barrel.

The P7M8 and Wilson Combat ADP are blowback designs, but have a gas port and piston to delay the opening and hence have smaller slides.

Is it the fact that the locking mechanism effectively adds mass to the slide by the fact that the barrel is now locked to the slide?

Have you held a Hi-Point slide. At what point does the designer say: yes, big enough. Does he take into consideration the force that the main spring is exerting on the slide via the hammer?

I know for a fact that the main spring does exert force on the slide because after having this shoulder surgery, I've found it necessary on some guns to cock the hammer in order to pull back the slide.

I'm glad you mentioned that you had seen slow-motion videos of guns shot without recoil springs and they remained locked. That says that the recoil spring doesn't contribute much to the equation. What I'm wondering is how much the main spring contributes to the equation and if reducing that force would be enough that the slide might start moving backward prior to the bullet leaving especially in a reduced size gun like the Officer's model where you don't have as much mass in the barrel or slide.

["DoubleAction"]

TMan; This might bring up another subject in mind :

Factory Loaded Ammunition vs Hand Loaded Ammunition

;D ;D

["DoubleAction"]

www.m1911.org/loader.swf

TMan : "Is it possible that by reducing the tension on the mainspring that the slide could start moving too early and effect accuracy? "


TMan; Do the pencil test on your pistols and how the pencil goes.

Take ordinary new wood pencil , unsharpened, with a new eraser, insert it in the barrel, and pull the trigger in a safe direction. Do this with the 1911s, Sigs, and other pistols that have and report the results to us.

Most of the time, the lighten mainsprings of the custom 1911s will still out hurl the pencil at greater distances, than most stock pistols with stiff mainsprings.

[TMan]

"New pencil" - I'll pick some up at the store tomorrow if they still make them. I have one around somewhere, but it is really old. I assume you are looking for a soft cushioning for the firing pin to hit? Why? it normally hits a metal primer. Why wouldn't a wooden dowel work as well?

The YouTube video was interesting. Was it my eyes or was the slide moving backward before the bullet was leaving the barrel?

The link: "http://www.m1911.org/loader.swf" didn't work for me. Perhaps because I don't have a login at that site. I joined a 1911 site a few years ago and made a comment about something getting sucked in. Apparently "suck" like "gay" has had its meaning change over time. Anyhow, I got a gig for using profanity. I complained to the administrator and was told that I should be able to express myself without using profanity. I pleaded my case that in the context it wasn't profane, but to no avail. It ticked me off and I thought it was childish so I stopped going there.

Getting back to hammer springs. Are you telling me that the custom guns have stronger hammer springs? I suppose there could be other factors such as friction in other words the custom gun parts are polished to the point that as the hammer falls there is less friction so even with a lighter spring the strike against the firing pin is greater.

[MLB]

I think that if you look closely at DA's emerging bullet picture above, you'll notice that the slide has indeed moved a small amount by the time the bullet leaves the barrel (see the guide rod?)

The barrel is still locked to the slide however, and it seems clear that the bullet will be way downrange before the two part ways.

I think your reduced mainspring would theoretically affect the cycle time (reducing it), but doubt that it would be significant.