Sear Spring Question ?

Ok I was weighing my hardball gun trigger and it won't lift the 4lb weight . My friend says all you have to do is bend one of your sear spring fingers and your good to go is this right ? and if so which sear spring finger do I bend. Now I don't know yet if I have a 3 finger spring or a 4 finger spring but in any case which one would I bend if this is the correct method to fix this or what is the correct method to fix this ?
                                                                                              Thanks in advance for all your guys help.

The left finger controls the pressure of the sear against the hammer.  The middle (on a 3-finger spring) controls the pressure against the trigger itself.  You can increase the pull weight by bending either the left or middle finger.  If it functions ok otherwise, I would probably bend the middle.  If it is way off, you may need to bend both.

I got it Thanks Dr. Don thanks !

Actually your gun is broken. Bad.  Real bad.  You need to sell it.  I'll give you a dollar.  :pirat:

Its better to feel the trigger, as it is now hammer cocked, unloaded how much tension do you feel when taking only the slack up? It should be about the pressure of pushing on a ink pen to put the point out, if its lighter then bend the center leg down slightly, little goes a long way with the sear spring, if the pressure feels good then bend the left leg a little till it picks up 4.25 cause it will usually get a little lighter after some use and this way it stays legal. final test, lock slide back put a dummy round or empty shell in the chamber then using the slide release drop the slide and be sure the hammer doesn't follow, if it does you need more weight on the left leg or a new sear.

A good rule of thumb is to put half the weight on the disconnecter leaf and half on the sear leaf. If disconnecter is to light it can double or go full auto. If you take grip safety off and put mainspring housing in with the hammer strut sticking out the rear of frame and hammer down, you can pull trigger and feel and weigh the center leaf only. Put half the weight on it. Now adjust sear leaf to weight you desire.
Jon

On a  bullseye gun thats 1.75 lb on the disconnecter leg? That sounds very heavy
to me and more like what you might find on a defense weapon.  Curious what other " bullseye gunsmiths" opinions on this are.

What Jon said is about what I go for as well.  I usually try for a 50/50 start between sear and disconnector leaf tension.  If customer wants a sharp snappy trigger return I'll go more to a 60/40 favoring the disconnector leaf.

Jon Eulette wrote:A good rule of thumb is to put half the weight on the disconnecter leaf and half on the sear leaf. If disconnecter is to light it can double or go full auto. If you take grip safety off and put mainspring housing in with the hammer strut sticking out the rear of frame and hammer down, you can pull trigger and feel and weigh the center leaf only. Put half the weight on it. Now adjust sear leaf to weight you desire.
Jon

I agree.. I want lots of positive tension on the trigger bow and disconnector..

Great info, never really heard much of the 50/50 setup, most books and other info just says very minimum needed to reset disco should be no lower than 8-10 oz's.

It's merely take up pressure...Example: 2 lbs of take up stops at the sear.. Now, it still takes 3.5 / 4 lbs to break to shot..
I personally advocate a positive, smooth, take up pressure...It's good insurance against doubles from trigger bounce, and aids recovery during sustained fire. I think the shooter benefits from a strong reset "click".. You are assured of exactly where you are in the process, if you are reading and feeling the trigger.

confused... if 2 lbs is take up then would not sear pressure just be additional 1.5lbs for a total of 3.5lbs ?

Well as it turned out I moved both the left and middle fingers just a little and the trigger still feels good. I didn't know to check for slam fires. I just stepped out back and dropped the the slide several times on a live round and didn't have a single slam fire but thanks for mentioning it DavidR and thanks for all the advise on this matter.

The responses to this post are a simplification. If you get anal you can get into the positive or negative hammer deflection (True Radius ). Sear engagement depth into full cock notch. The applied force from mainspring via the hammer strut. The affect of the grip safety leaf causing a increase in trigger pull because sear spring is severely out of spec/incorrect bend. Roll trigger vs. crisp. They all have an effect on what's going to happen when adjusting the sear spring. So in simplest terms if trigger is 3.5# and 2# is on the middle leaf (disconnector) than 1.5# is on the left leaf (sear). And a reminder: Just because it's 3.5# doesn't make it a nice trigger!!! It's so much more than sear spring pressure.
Jon

Ok thanks Jon

There is a lot more to all this for sure , That's why talks like this with knowledgeable people willing to share is what makes this forum a great resource!!

I agree 100%

Yes there is quite a bit that influences the "trigger pull" especially the disconnecter. Being the 1911 is one of the very few guns that has a disconnecter. Most have the transfer bar disconnected and do not have a separate device. And there is quite a few different styles of "trigger pulls" that various shooter like. Crisp like breaking glass is not possible simply because something must move so it only feels that way. Roll is another style but if I were to ask 10 people to describe the roll they like I'll get 10 different answers. That being said the new shooter is left to getting the weight to legal amounts because there is no requirement of trigger type (except release trigger) in the rules. Get it legal then determine the pull style.

I would like to see pictures from gunsmiths of what a properly adjusted 3.5lb bullseye sear spring profile should look like. In books on the 1911 most times you will see a pic like the bottom one I have posted, the top spring is one I adjusted to have 1.5lb on the disconnecter and 2lbs on the sear. Just curious if the look fits what they have expressed as the correct way to adjust the spring.

DavidR wrote:I would like to see pictures from gunsmiths of what a properly adjusted 3.5lb bullseye sear spring profile should look like. In books on the 1911 most times you will see a pic like the bottom one I have posted, the top spring is one I adjusted to have 1.5lb on the disconnecter and 2lbs on the sear. Just curious if the look fits what they have expressed as the correct way to adjust the spring.

Wouldn't that depend on the steel used for the spring. Some might not need to be adjusted as much, some more.

- Dave

most sear springs are made either like the top pic or like the bottom, except the Clark 4 leg, the bend might be slightly different but it will still be close to the same profile

The grip safety spring in the lower photo is the best way to bend it. The lower safety spring will be against the frame and will not effect the other two. The upper safety spring may change the pull weight depending on how much the grip safety is pushed in.

Still would like to see a picture from one of the smiths of a properly formed 3.5 lb sear spring

David, the appearance of that spring is going to change from gun to gun.  I'll take a couple of pics of guns I'm waiting to ship back to owners today or tomorrow and post them then.

The trigger on the 1911 is not a precision target system. We do the best we can, but it leaves much to be desired.. The sear spring is trapped by the main spring housing, which limits the sear springs ability to flex.
I relieve the housing to allow more range of motion.. It produces a more repeatable condition. Bending the spring leaf can drive you nuts. It's like playing the lottery.. Hit & miss, mostly 99.9% miss. Then it changes, so I avoid bending if possible, and adjust with a screw in the main spring housing.. It's easier, and seems to last much longer.  Not allowed on CMP guns, but I don't build them any longer, so lucky me..