Trigger job questions

[BlueOvalBruin]

I'm getting close to finishing up the trigger job on my single stack but am having issues getting down to the weight I want. I'm at 3.5lbs right now and want get down to 1.75lbs. I have a perfectly flat engagement between the hammer and sear and the engagement is even on both sides. The current setup is crisp but not glass rod-like and does not follow. I was a tad conservative on the secondary angle and can probably take a little more off there if needed to reduce engagement. Force on the middle spring is roughly 8oz and sear and middle combined is 1.5lbs. I know I will need to take a bit more off the sear spring to reach my goal but won't make enough of a difference by itself. I did notice that the white ceramic stone didn't really leave the super nice mirror surface finish I was expecting. Is a mirror finish even beneficial? If so, what are people using to get it? I've used whet stones up to 8000 grit on kitchen knives but those stones are pretty big.

One weird thing I should mention is that the fixture needed to be set at 23 clicks to get parallel engagement between the hammer and sear primary angle.

BTW, I'm using cylinder and slide hammer and sear with svi triglide disconnector, sear spring, and triggerbar. I am also using a power custom jig. Brownells action lube on engagement surfaces.

Thanks.

[rooster]

Sounds as if you are on tract, I use about 1/3 of the pull weight on my disco the rest is on the sear spring. I use a 19 lb. mainspring, a sti trigger so i don't have to worry about trigger bounce. I don't use too much of a releif angle, the more relief angle the deeper the sear will go into the hammer hooks. I use a 1/8 thick shim to do my releif angle, I know all the books say use a .020 shim but that is what I use. I don't count clicks, I set the stone so that it forms a 90 degree angle to a line drawn through the center of the sear pin hole to the edge of the sear nose. This gives you a posistive relationship to the hammer. then stone as necessary to achieve a neutral angle. To check hammer sear contact sharpie sear nose install trigger set in gun pull trigger several times then check to see how much of the sharpie is removed and dress hammer hooks so that you have full contact with sear. Go over to 1911 forums and do a search, log man has posted detailed pictures of the jig set up. Oh yea sear length should be between .454 to .460. I use egw's sears to set correct angle as they are about perfect. I color the primary angle with a sharpie and set the jig so that when the stone removes all of the sharpie that is the proper angle. Just remember when getting pulls this low everything has to be perfect, make sure you test fire with one round then 2 and so forth.

[want2race]

What main spring are you using? Of course some will argue that it "shouldn't matter". I say it does. Friction is friction.

I use a different sear jig so I can't answer that one. Try moving the stone side to side to get a polish on it. I cut mine first, then go side to side with the stone to polish it.

Carefull with your secondary angle. If you want sub 2#, you need some engagement surface for it to hold onto. I like a little "push" to my trigger pull. It's only noticable when shooting groups (slow fire). At speed I don't feel pretravel, reset, glass-rod, push, nothing. Just recoil. I had mine down to 1.5# and it lasted a long time. Now I'm at 2# because I wanted more reset strength.

[stardust tommy]

how high is the full cock hammer hook and is is 90° or less ? should be 90° and .018 tot .020 high (for competition use)

gr T

[rooster]

I forgot to mention that it is most important that your half cock notch works correctly, and that all safeties work properly. Once you start stoning sear angles the thumb safety may not block the sear this needs to be checked for proper operation.

[BlueOvalBruin]

The hammer hooks came from C&S set at .018”. The hammer was not looking good under a microscope (undercut and not straight) so I filed it with a hammer file until it was uniform and 90deg. Then I stoned it to make it smoother. Still has a couple thou of undercut though, considering I have a good amount of engagement I wonder if the sear is catching the undercut lip on the way out.

Using a Wolff 17lb mainspring.

I’ll have to measure the sear length now, I can imagine if the sear is too short it would cam the hammer back on the way out (although I can’t perceive any hammer movement).

I have a brand new safety since the old one was only single sided. By the way I’m putting this trigger in a kimber .40. Are kimbers frame problematic with trigger jobs?

Thanks.

[want2race]

The C&S/Extreme Engineering hammers all have a slight undercut at the bottom corner of the hook. They appear to be wire EDM'd and that is a byproduct. As long as your secondary angle isn't too large it shouldn't be to much of a problem. I have experienced the sear diving into the the wire "turn around" space before though.

[rooster]

Don't worry about the undercut on the hammer the sear nose doesn't go that far in anyway. The hammer file is good for everything else axcept squarring hammers. Good hammers today like the one you have are fine right from the factory. Just a liitle stoning of the hooks is all that is needed. One thing that is good to have is the pin set from Brownells that lets you look at your sear and hammer engagement outside the gun on your frame.

[BlueOvalBruin]

I use a portable digital microscope that gives me a good view of the hammer/sear engagement and lets me closely inspect the parts themselves. I also have a set of pin gauges which I use to check the engagement on both sides of the frame. The frame holes seem parallel to each other but I can’t say whether the distance is within spec.

The C&S hammer was not square, I first used the stone but it was not aggressive enough to give me a flat surface. The file helped me get there and I finished it with a black then white stone. The hammer metal seemed somewhat porous under the microscope, probably not a problem because the sear was not porous.

I should take some pictures of the parts with the digital microscope when I get some time.

[Ross Carter]

Have you tried using a good light oil on the hammer, sear and all the trigger system parts instead of the the action lube? With some combinations you will see a lighter trigger pull than with the grease.

[rooster]

When looking through the back of your frame can you see your hammer lift as you are pulling the trigger? If so you might need to lower the fixture to get more of a neutral engagement on your sear. You can also check this by looking at your trigger from the side as you pull it. After the take up you will see movement just before the hammer falls. You are trying to get this movement as small as posible. What you are shooting for is the hammer to fall as soon as the trigger begins to move.

[BlueOvalBruin]

I perceived no motion of the hammer, but it would tough to see without some sort of video capture and slow-mo playback with a somewhat crisp trigger like this one is.

I already have neutral engagement, but neutral engagement on a short sear could cause a small amount of hammer camming. I should chop up a mainspring to see what contribution the mainspring has to the trigger pull weight “stack”. A big difference compared to my other gun would tell me there’s some camming going on. In that case its time to get a new sear.

I need to put these parts in a CMM (including frame) to see exactly what kinds of dimensions I’m dealing with.

[rooster]

If you can't see it raise then you are good. I guess I'm starting to loose tract of the post. What exactly is your problem with this trigger? You say it is crisp, does not follow, and no creep what more do you want? It sounds like you have a real nice trigger.

[BlueOvalBruin]

It's too heavy at 3.5 pounds. 95 out of 100 people would say "Hey, nice trigger", but I prefer a lighter pull around 1.75lbs for an iron sighted gun and 1.5lbs for my open gun. Although I think I’ll probably end up with a 1.5lb trigger for my iron sighted guns too within the next year. With a lighter trigger pull I get a feeling that my brain is directly coupled to the gun.

[mike cyrwus]

The C&S/Extreme Engineering hammers all have a slight undercut at the bottom corner of the hook. They appear to be wire EDM'd and that is a byproduct. As long as your secondary angle isn't too large it shouldn't be to much of a problem. I have experienced the sear diving into the the wire "turn around" space before though.

Shaun, I would call that undercut a feature, as opposed to a by-product.

[rooster]

Have you tried bending the sear spring to get to your 2 lb weight? It sounds as though you have done everything correctly. You might alresdy be there.

[BlueOvalBruin]

I was going to take some more off the left leg of the sear spring, the middle is already pretty low. I'm going to try a 15lb mainspring too if I can find one soon.

[Steve L]

I use a portable digital microscope that gives me a good view of the hammer/sear engagement and lets me closely inspect the parts themselves. I also have a set of pin gauges which I use to check the engagement on both sides of the frame. The frame holes seem parallel to each other but I can’t say whether the distance is within spec.

The C&S hammer was not square, I first used the stone but it was not aggressive enough to give me a flat surface. The file helped me get there and I finished it with a black then white stone. The hammer metal seemed somewhat porous under the microscope, probably not a problem because the sear was not porous.

I should take some pictures of the parts with the digital microscope when I get some time.

I prefer an India stone and Arkansas stone over a file when it comes to the trigger group parts.

[BlueOvalBruin]

I use a portable digital microscope that gives me a good view of the hammer/sear engagement and lets me closely inspect the parts themselves. I also have a set of pin gauges which I use to check the engagement on both sides of the frame. The frame holes seem parallel to each other but I can’t say whether the distance is within spec.

The C&S hammer was not square, I first used the stone but it was not aggressive enough to give me a flat surface. The file helped me get there and I finished it with a black then white stone. The hammer metal seemed somewhat porous under the microscope, probably not a problem because the sear was not porous.

I should take some pictures of the parts with the digital microscope when I get some time.

I prefer an India stone and Arkansas stone over a file when it comes to the trigger group parts.

The first thing I tried to true up the hammer was my India stone. It was not aggressive enough though so I went to the "hammer squaring file" with 2 safe edges. Then I finished the hammer with my India and ceramic stones for a nice surface finish (but not an awesome finish).

Back to one of my original questions, what can I use to get that super fine mirror finish that I see on some components, like my sv trigger parts. My ceramic stones aren't fine enough.

[Steve L]

I never used it on trigger components but you can try 2000 grit sandpaper then a scotch brite pad to finish it off

[rooster]

I have the white ceramic stone frome Brownells which works really well. If you want a real polish get one of Spyderco's ultra fine triangular cereamic stones.