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Sear Spring question


ArrDave

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I'm no gunsmith, as evidenced by the title of this thread, but I'm looking at lightening the factory pull of my new E Series. Yes, I could go pay a gunsmith for a good trigger job but am excited about the prospect of doing some of this myself as I'm new to the 1911 platform and have not had either gun apart entirely yet. I've watched the videos in detail stripping and I am confident that I am capable of at least getting them apart and put back together. So the question: I'm thinking about one of these Cylinder & Slide Sear Springs and a lightened mainspring (19# to match my Dan Wesson Valor which comes stock with a 19# MS).

Is this something I can do as a hobbyist or better to just let my gunsmith take care of it?

Can you good folks point me to "the best" resources on educating myself on this?

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If you’re knowledgeable enough to remove and re-install the grip safety to access the sear spring, then go for it.

I recently installed the C&S 4 lb trigger pull set http://www.cylinder-slide.com/index.php?app=ccp0&ns=prodshow&ref=CS0212, which includes the lightened sear spring, on a Rock Island Armory GI model 45. The install was fairly easy and I didn’t need to adjust the sear spring.

If you install your sear spring improperly, the hammer might not stay cocked or you might not be able to engage your thumb safety. So even though you might be able to install the sear spring without removing the grip safety, I’d recommend removing the grip safety to make sure you get everything lined up properly.

If you do mess up, then it’s easy to remove the sear spring with the grip safety still installed and try it again.

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the key KEY key thing here, if you futz around with it yourself is to test it, do a full functions test first after working on it, and then put it through the wringer during live fire; expecting the darn thing to do full auto if you didnt get it right. So only load one or a couple rounds at a time.

If you do not know what a functions test is, for the 1911; then stop and go to a gunsmith now.

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It'd be going on a S&W E series. It's not my primary competition gun, I got it to be a backup to my Valor heaven forbid it should have a stoppage. I've swapped out every part there is to swap on a Glock before, but interested in becoming knowledgeable on "real" guns. As it is the Valor's trigger is way way nicer.

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You need to understand the spring has nothing to do with how low the trigger pull can be adjusted.

What matters is the quality and geometry of the sear, disco, and hammer.

You can get jigs and correct for geometry, but you can't make the parts harder (allowing more aggressive geometry) or fit better (pin holes could be sloppy).

If you want a good trigger job, step one is to get the best ignition kit you can. C&S, SV, and EGW all make great base parts that will fit properly.

The C&S will basically drop in, assuming pins fit well. The others will need fitting, but the quality is at least as good.

Proper pins is step 2... use drill rod for perfect fit.

Step 3 is addressing the sear/hammer geometry. It's not worth doing this work at all if your parts are junk.

Step 4 is bending the sear spring to get the pull as low as you want. If you start here, you'll get hammer follow and potentially full auto problems. If you do the geometry on parts that aren't perfect fitting and super hard, you'll get these problems as your geometry wears into brokenness. That's why this is step 4, not step 1.

The best sear spring you can get is the colt part. Everybody just repackages that anyways. SV makes a titanium one, but I'm not convinced it makes any difference.

Step 5 is test like hell.

Optionally, you can replace the trigger and bow itself if the stock fit is not good. This is not often necessary, though. If your stock trigger is very heavy, you'll get doubles at low pull weights, but I don't think any manufacturer is even making heavy triggers anymore (since it's such a major safety issue).

My suggestion to you is to go buy the rest of a C&S kit (sear/hammer/disco) and then start from there. It's 99% likely you won't need to adjust the geometry with that.

On your next trigger job go buy sear/hammer stoning jigs and start with EGW parts.

If you want better than that, then you're going to need an optical comparator, so let's just not go there.

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Just buy a Colt spring in case you mess up. Not likely. I don't think it's as dangerous as the previous post leads on. Just tweak the pull down to 2.5-3 and test for hammer follow, etc. Load only a few rounds in each mag a for a bit until you're sure the gun won't double.

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The sear spring does affect trigger pull, but not 100%. One leaf of the spring pushes on the trigger bow, one on the sear so both of those springs contribute directly to trigger pull weight.

A significant part of trigger pull weight is caused by the sear pulling past the hammer hooks and in the process, deflecting the hammer slightly rearward. So the mainspring (hammer spring) as well as the sear cuts affect trigger pull.

HOWEVER:

You can't just bend the sear spring any amount you want to lighten the pull. If you get too light, you can get hammer follow.

If you want to learn about the 1911, the best books are shown below. the Wilson manual is $10 and worth it's weight in gold.

Kuhnhausen 1911 Manuals (two volumes)

http://www.brownells.com/books-videos/books/gunsmithing-books/handgun-gunsmithing-books/jerry-kuhnhausen-the-u-s-m1911-m1911a1-pistols-a-shop-manual-prod13815.aspx

http://www.brownells.com/books-videos/books/gunsmithing-books/handgun-gunsmithing-books/jerry-kuhnhausen-the-colt-45-automatic-prod13805.aspx

Wilson 1911 Manual

http://shopwilsoncombat.com/Wilson-Combat-1911-Auto-Maintenance-Manual-by-Bill-Wilson/productinfo/401/

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You need to understand the spring has nothing to do with how low the trigger pull can be adjusted.

What matters is the quality and geometry of the sear, disco, and hammer.

You can get jigs and correct for geometry, but you can't make the parts harder (allowing more aggressive geometry) or fit better (pin holes could be sloppy).

If you want a good trigger job, step one is to get the best ignition kit you can. C&S, SV, and EGW all make great base parts that will fit properly.

The C&S will basically drop in, assuming pins fit well. The others will need fitting, but the quality is at least as good.

Proper pins is step 2... use drill rod for perfect fit.

Step 3 is addressing the sear/hammer geometry. It's not worth doing this work at all if your parts are junk.

Step 4 is bending the sear spring to get the pull as low as you want. If you start here, you'll get hammer follow and potentially full auto problems. If you do the geometry on parts that aren't perfect fitting and super hard, you'll get these problems as your geometry wears into brokenness. That's why this is step 4, not step 1.

The best sear spring you can get is the colt part. Everybody just repackages that anyways. SV makes a titanium one, but I'm not convinced it makes any difference.

Step 5 is test like hell.

Optionally, you can replace the trigger and bow itself if the stock fit is not good. This is not often necessary, though. If your stock trigger is very heavy, you'll get doubles at low pull weights, but I don't think any manufacturer is even making heavy triggers anymore (since it's such a major safety issue).

My suggestion to you is to go buy the rest of a C&S kit (sear/hammer/disco) and then start from there. It's 99% likely you won't need to adjust the geometry with that.

On your next trigger job go buy sear/hammer stoning jigs and start with EGW parts.

If you want better than that, then you're going to need an optical comparator, so let's just not go there.

That makes sense, but the fitted/stoned kits are like $180 which are a bit out of my budget for now. I'll seriously consider this, just not right away.

The sear spring does affect trigger pull, but not 100%. One leaf of the spring pushes on the trigger bow, one on the sear so both of those springs contribute directly to trigger pull weight.

A significant part of trigger pull weight is caused by the sear pulling past the hammer hooks and in the process, deflecting the hammer slightly rearward. So the mainspring (hammer spring) as well as the sear cuts affect trigger pull.

HOWEVER:

You can't just bend the sear spring any amount you want to lighten the pull. If you get too light, you can get hammer follow.

If you want to learn about the 1911, the best books are shown below. the Wilson manual is $10 and worth it's weight in gold.

Kuhnhausen 1911 Manuals (two volumes)

http://www.brownells.com/books-videos/books/gunsmithing-books/handgun-gunsmithing-books/jerry-kuhnhausen-the-u-s-m1911-m1911a1-pistols-a-shop-manual-prod13815.aspx

http://www.brownells.com/books-videos/books/gunsmithing-books/handgun-gunsmithing-books/jerry-kuhnhausen-the-colt-45-automatic-prod13805.aspx

Wilson 1911 Manual

http://shopwilsoncombat.com/Wilson-Combat-1911-Auto-Maintenance-Manual-by-Bill-Wilson/productinfo/401/

That's probably a good starting point, I'll definitely check it out.

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Step 4 is bending the sear spring to get the pull as low as you want. If you start here, you'll get hammer follow and potentially full auto problems.

Thousands of people start at step 4 with no problems. I've done it on 3 different guns and I know f*#%-all about gunsmithing.

Assuming your trigger is already reasonably crisp, and you only want to reduce the pull from 5 lbs to 3.5 lbs (or whatever), it's easy and safe to do that by tweaking the sear spring and trigger return spring and leaving everything else alone. The sky is unlikely to fall.

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From the Brownells article (which also has pictures) on how to adjust a sear spring accurately:

http://www.brownells.com/.aspx/lid=10297/GunTechdetail/2-lb-Trigger-Pull?avad=avant&aid=41227&cm_mmc=affiliate-_-Itwine-_-Avantlink-_-Custom+Link

SEAR SPRING PREP — The adjustments that I make to the sear spring are the only variables I use to determine final trigger pull weight. The lighter I set the sear spring, the lighter the final pull weight and vice versa.

The 1911 Auto sear spring is a flat spring that has three legs and it works as a return spring for the sear, disconnect and grip safety. When viewed from the rear, the leg on the left works the sear, the leg in the center works the disconnect and the leg on the right works the grip safety.

Install only the trigger, magazine catch, disconnector, disconnector/ sear pin, sear spring and mainspring housing into your bare frame. Notice that when you pull on the trigger, you are feeling spring tension from the center or disconnector leg of the sear spring.

Use an RCBS Trigger Pull Gauge (#747-094-500) to measure the disconnector spring tension. Adjust the tension of the center leg of the sear spring by bending the spring leaf above the pivot point at the mainspring housing. Bend the spring outward to create less spring pressure, bend it inward to create more spring pressure.

Adjust the spring pressure until you get a reading of 8 oz. Pull rearward on the trigger with the Trigger Pull Gauge only enough to cause the disconnector leg to move. If you pull it too far, you will also engage the sear spring leg and that will cause you to get a false reading on the gauge.

Next, add in the sear to the limited assembly. Again, measure the spring pressure with the Trigger Pull Gauge. We now need a total of 16 oz. of spring pressure with both the disconnector and sear legs of the sear spring engaged. If you get a reading that is either more or less, bend the sear leg of the spring in or out until you get the 16 oz. reading. This is really the only variable I do to my trigger jobs. If I need a heavier weight trigger pull I adjust the tension of these two spring legs upward. Remember, both legs of the sear spring need to be adjusted equally.

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Step 4 is bending the sear spring to get the pull as low as you want. If you start here, you'll get hammer follow and potentially full auto problems.

Thousands of people start at step 4 with no problems. I've done it on 3 different guns and I know f*#%-all about gunsmithing.

Assuming your trigger is already reasonably crisp, and you only want to reduce the pull from 5 lbs to 3.5 lbs (or whatever), it's easy and safe to do that by tweaking the sear spring and trigger return spring and leaving everything else alone. The sky is unlikely to fall.

People have died from going to low and doubling (at which point you can't control where the muzzle is pointing). Caution is required, as you never know what any individual is starting with.

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My advice is too just do the sear spring adjustment. But buy a Wolff sear spring first, and work on that. Keep the original factory spring untouched, in course you mess up the Wolff sear spring. This was you can always fall back to the factory set up.

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Although bending the sear spring may have some limited effect on trigger weight, it's only a small part of the equation. Running a very light mainspring is also less than ideal and just a shortcut for those who don't know how to setup the hammer/sear/disco properly. Surface finish and parts prep is also a big factor. Drop in parts work ok sometimes, but rarely are anywhere near as good as a properly done professional job. If you're intent on doing yourself, read as much as you can and get a good understanding of how the gun works and how the parts interact with each other. It's not rocket science. If you have a decent mechanical aptitude, you can get it. After that, get the right tools and quality parts to start, then go slow, exercise care and patience, and test it out (with one round to start, then two, etc.).

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Just make sure that you do ALL of the safety checks before putting any live ammo through the gun, and when you DO put live ammo through for the first time, start with 1 round, then 2, then 3, etc. The LAST thing you want to do is stuff a full mag in there on the first go, and have the thing go full-auto on you!

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many good suggestions above. Let me make it clear that I was only referring to adjusting the spring with the existing OEM parts in a high quality gun (2 sti's and a sig), and not trying for superlight break or actually modifying the sear or hammer, but simply reducing the safe factory trigger pull slightly.

I think that's well within the capabilities of any reasonably safe person who can detail strip a 1911.

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I am putting in a midway order today so I'll get a guinea pig sear spring and start there. I'd honestly be happy with about 4-4.5# pull. The trigger is again "OK", not great but not bad. As far as a practice gun is concerned I don't mind having it need a little more attention to trigger pull.

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Get a trigger pull gauge on your order so you can go in small increments (testing along the way).

or make your own by duct-taping a ziploc bag to a plastic coat hanger. I just keep putting bullets in the bag until the trigger breaks, repeat a couple times, then weight the whole mess (coat hangar included). It gets repeatable accurate results on the cheap for folks that only do this sort of thing once or twice.

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Get a trigger pull gauge on your order so you can go in small increments (testing along the way).

or make your own by duct-taping a ziploc bag to a plastic coat hanger. I just keep putting bullets in the bag until the trigger breaks, repeat a couple times, then weight the whole mess (coat hangar included). It gets repeatable accurate results on the cheap for folks that only do this sort of thing once or twice.

This is brilliant. Thanks for the tip!

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True, but I also get a lot of use from the pull gauge using the weigand extractor tension gauges. I end up fixing a bunch of people's 1911's and my pull gauge gets a lot of use.

They're little brass pieces you slide under the extractor (slide removed) and then pull out with a pull gauge to see how much extractor tension there is.

Then there's this extractor bending jig you can use to dial in just the right amount (you can bend it manually, though, but it's harder to make smaller changes).

And then, if you have issues down the road, you measure it again and see if yoru kimber extractor is indeed a turd and won't hold tension and that you need to replace it with EGW or aftec (which I've never seen lose tension).

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Get a trigger pull gauge on your order so you can go in small increments (testing along the way).

or make your own by duct-taping a ziploc bag to a plastic coat hanger. I just keep putting bullets in the bag until the trigger breaks, repeat a couple times, then weight the whole mess (coat hangar included). It gets repeatable accurate results on the cheap for folks that only do this sort of thing once or twice.

Or use a luggage scale with a hook if you got one handy. My luggage scale was accurate enough to measure the 6 lb pull on my stock Rock Island .45 and the lightened 4.25 lb pull after I installed the C&S drop-in kit.

From what I read on the S&W E-Series, it was supposed to have a stock 4 lb trigger pull. What happened to the OP's E-series gun?

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