Sear Jig--Is It Really Necessary?

[FNULNU]

Last month I started work on a 1911. It isn't my first 1911, but my first attempt in building one from parts. I've been lurking here while I worked on everything but the fire control mechanism.

Now that I'm at what could be the last major step of fitting my sear and hammer, I fear that I might have to spend more on a jig. My wife tells me that my project has encountered some budget overruns, and asked if I was done buying things from those folks in Montezuma, Iowa. I've looked over the Poor Man's Trigger Job, and I don't see a jig mentioned.

The pistol is meant to be a target pistol, but I'm more concerned with function than getting a 3.0000001 pound pull. Anywhere from 3-5 pounds and a functioning pistol would make me estatic. I'll perfect it later as I learn more.

So, can a first-time builder fit the sear and hammer without the extra expense of the jig? I'll be away until tomorrow afternoon, and I'll post some photos of my project then.

Thanks for the help,

Alan

[Hawkmoon]

I have not yet used a jig. I consistently obtain clean, crisp triggers around 4-1/2 to 5 pounds (which is my choice, I could get lighter) using the steps outlined in "The Poor Man's Trigger Job."

Tell your wife the budget is safe.

[mr1911]

If you are buying a matched sear and hammer, don't worry, I got a wilson value-line sear/hammer combo years ago for my home built frankengun and it was absolutely perfect out of the box.
However if you are trying to fix a bad factory trigger like my old Colt 1991's ALL had, don't try to fix them without a propper jig and stone, it will be an excersize in futility.

[log man]

The trigger pull weight isn't the sears problem to begin with, a standard sear and hammer only takes a pound or so to release without the sear spring in place. So when you're talking a 3#- 5# trigger it's mostly sear spring adjustment. The sear and hammer hook engagement can by design give a pull from very gritty and creepy to crisp and short or smooth and short or long if you like, it's the sear and hammer hooks that give you what you want in feel. And it's the sear spring adjustment that controls the pull weight.

LOG

[wichaka]

...and the main spring too.

[kenhwind]

A sear jig may not be necessary, but some really good honing stones are.
With a good trigger a factory mainspring is acceptable for me.
Does the mainspring make a difference, sure it does. In trigger pull weight, but not in trigger pull feel.

[mr1911]

The trigger pull weight isn't the sears problem to begin with, a standard sear and hammer only takes a pound or so to release without the sear spring in place. So when you're talking a 3#- 5# trigger it's mostly sear spring adjustment. The sear and hammer hook engagement can by design give a pull from very gritty and creepy to crisp and short or smooth and short or long if you like, it's the sear and hammer hooks that give you what you want in feel. And it's the sear spring adjustment that controls the pull weight.

LOG

Sorry, but I've had lousy factory sear/hammer combos that were over 8lbs, and with no spring adjusment or swap, just a new matched hammer & sear it dropped in half. Yet I've had matched hammers and sears that would barely adjust 1 lb max by tunning the sear spring. hammer/main springs make a huge difference along with correctly prepped hammer/sear surfaces.

One thing that we can all agree on though is they all add up to either a good or bad trigger pull.

[log man]

Sorry, but I've had lousy factory sear/hammer combos that were over 8lbs, and with no spring adjusment or swap, just a new matched hammer & sear it dropped in half. Yet I've had matched hammers and sears that would barely adjust 1 lb max by tunning the sear spring. hammer/main springs make a huge difference along with correctly prepped hammer/sear surfaces.

One thing that we can all agree on though is they all add up to either a good or bad trigger pull.
You've got nothing to be sorry about, we've just had very different experiences.
I've never had an 8# trigger, but am aware they exist and were the original spec. The main spring can make a difference, but not huge. If the hammer hooks are longer than the sear face that will do it or if the sear face isn't machined on the neutral angle that is spec. that will make a difference. As the hammer is cocked more as you pull the trigger and is how some increase past what the sear spring you have will, all true.

But if you have a 5# trigger and perfect the sear and hammer hooks to a short crisp pull and don't touch any thing else you may drop some pull weight, but you can't get it down to 2# or less without adjusting the sear spring.

To see just what the pull is of your sear and hammer and mainspring, remove the GS and sear spring, reassemble. With a small punch hold the sear legs forward while you cock the hammer and push the disco up and check the pull with a trigger gauge, whatever it is will be a constant in the whole with the rest being the sear spring.

To more adequately answer the OP's question, a great trigger can be done without the aid of a sear jig. If the parts are from a reputable supplier a 3#-5# will not be a problem.

LOG

[FNULNU]

Good morning everyone. Thanks for the quick replies. With Hawkmoon's and Logman's replies, I have decided to forego the jig. But, MR1911 has me wondering if any work at all is necessary.

If you are buying a matched sear and hammer, don't worry...

I don't think the hammer and sear are a matched pair, but they are all from the same manufacturer. Here is what I have:

STI Match Grade Sear (http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=12428&title=1911%20AUTO%20MATCH%20GRADE%20SEAR&s=29344#29344)

STI Tool Steel Spur Hammer (http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=12429&title=1911%20AUTO%20HAMMER&s=29347#29347)

STI Disconnector (http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=12426&title=1911%20AUTO%20EXTENDED%20SAFETY&s=29334#29334)

STI Extended Single Safety (http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=12426&title=1911%20AUTO%20EXTENDED%20SAFETY&s=29334#29334)

When the pistol is assembled I can't seem to get it to cock. Just one very long and heavy hammer pull that never clicks. But, I also haven't fitted the safety yet.

http://southardandtussey.com/HammerSear.JPG
http://southardandtussey.com/hammerSearClose.JPG

[log man]

Do not fit the safety until you get the sear and hammer functioning safely and to your liking, as the fit can change. The thumb safety will not affect cock and release. While a sear jig isn't absolutely necessary it requires some understanding of what is the goal. A reluctance to buy inexpensive tools is not beneficial to your future gun work. If this is the only one you're going to do in your life, buy the tools anyway and sell them after. You can't adequately torque head bolts with an adjustable wrench.

LOG

[niemi24s]

When the pistol is assembled I can't seem to get it to cock.The hammer strut may not be centered and bottomed in the mainspring cap.

[kenhwind]

This is the set I have. Pricey, but everything needed is included.
http://www.brownells.com/aspx/NS/store/productdetail.aspx?p=868&st=080-785-000AA&s=3287

[FNULNU]

Do not fit the safety until you get the sear and hammer functioning safely and to your liking, as the fit can change. The thumb safety will not affect cock and release.


I have assembled the pistol and minus a slight grit in the trigger pull which I'm guessing is a trigger bow I haven't perfected. My naivete made me think the safety would drop in. I see where bluing is rubbing off--do I just file there?

[FNULNU]

This is the set I have. Pricey, but everything needed is included.
http://www.brownells.com/aspx/NS/store/productdetail.aspx?p=868&st=080-785-000AA&s=3287
Thanks Ken,

I added it to my favorites for a future purchase. Since my wife dropped the laptop down the stairs, I'm forced to get a replacement. I just can't afford a $100.00 single use tool right now. I also don't do enough gun tinkering yet to justify that purchase--yet.

[FNULNU]

I have assembled the pistol and minus a slight grit in the trigger pull which I'm guessing is a trigger bow I haven't perfected. My naivete made me think the safety would drop in. I see where bluing is rubbing off--do I just file there?

Disregard. The safety is too long to fit the catch on the slide. I will file and report back this evening.

[niemi24s]

The safety is too long to fit the catch on the slide. I will file and report back this evening.Wait! Stop!! Hang loose!!!

Before taking a file to the thumb safety to get it go up into the notch in the slide, make certain the problem is not that the slide sits too far back on the frame when the gun's in battery.

Does the back of the slide hang over the frame?

[FNULNU]

Does the back of the slide hang over the frame?

Only slightly, but you may be on to something. But, without any internal parts I can get the safety on and it doesn't clear the plunger tube without some contact there, so I still think the safety is too long.

[niemi24s]

. . .it doesn't clear the plunger tube without some contact there, so I still think the safety is too long.A little bit of slide overhang is no big deal, but the thumb safety should make no contact with the plunger tube.

If you want to check your thumb safety's dimensions, a blueprint for it is available in our Tech Issues section.

However, it could be interference between the thumb safety and the internal parts that prevents its engagement.

Regards

[FNULNU]

A little bit of slide overhang is no big deal, but the thumb safety should make no contact with the plunger tube.

If you want to check your thumb safety's dimensions, a blueprint for it is available in our Tech Issues section.

However, it could be interference between the thumb safety and the internal parts that prevents its engagement.

Regards

I can see where the sear is preventing insertion. Because I checked multiple times before I staked it, I know the plunger tube is in the right position, and not backwards. I also tried interchanging the safety with my Springfield. They aren't interchangable.