I have an early one.  I'm getting about 4.5lb on single and about 10.5 on binary for the second shot.  I cut my own carrier and brought the second shot down to ~6.5lb.

IIRC putting green springs on it lowered it closer to 4lb on single.

Okay.  Thanks for the response.  From the factory mine was about 6 1/2 pounds in semi-auto.  The first release in Echo was about 7 1/2 pounds and the second release was off my scale - well over 12 pounds.  I saw the youtube videos from Michael Bell for his bolt and bushing modifications and tried it.  The reduction in trigger pull weight was marginal at best.  I put the Hiperfire extra heavy green springs in it and that may have reduced it some, as well.  But again, any reduction was marginal.  I respectfully disagree with Mr. Bell with his assertion that the hammer block spring or placing a homemade vinyl bushing on the hammer release crane has anything to do with trigger pull weight.  The green springs may increase hammer speed, but in my estimation do not do much to reduce trigger pull weight.

I have been working on a spring change that will significantly reduce trigger pull weight in semi-auto and echo modes.  If anyone is interested I will post.

The bolt mod helps by changing the cam angle that activates the release shot. How much difference it makes will depend on how everything fits in your rifle. Generally you want the lever pushed forward as far as possible without keeping the carrier retracted.

The bushing mod can also affect that angle.

The green springs work by reducing tension on the primary sear surface. 

Did you hear there is version 2.0 for sale now?  Change is the trigger lock that allows you to use any full auto bolt carrier you want.  I called Fostech the next day after seeing this and they said I could buy a replacement trigger lock for $25.  That didn't really bother me.

What does chap me a bit is that the new version ships without the bolt carrier but the price is the same.  WTF with that?  Less material and cost to make for the same price???

You have to remember though that the first version was going to be the same price without the bcg, so really it just went back to the way it was again almost.

Here is the difference between the trigger locks. Original (left) and Echo II (right). They shaved off a bit of the metal at the top. That appears to be the only difference.

Do I need to call them for the new trigger lock or is there a link?

I would send them a message using the contact form on their website.  That's how I bought spare parts.
https://fostechoutdoors.com/shop/index.php?l=page_view&p=contact_us

the new one looks like the one they sent me back when the trigger came back from repair.

EDIT: I just tried mine on my standard M16 BCG and I could not get it to close. The ECHO II trigger lock must be different than the one they sent me but it sure does look like it

unless its broken they are going to want your money

https://fostechoutdoors.com/shop/index.php?l=product_detail&p=150

i called them, gave them my original order number (so that i wouldn't have to provide shipping info all over again) and charged it.  $25 + $3 S&H.

I fabricated a slave pin to facilitate disassembly and reassembly of the disconnector/trigger group. I took the factory disconnector springs to a local spring distributor and they measured them and determined they are 32 lb springs. They were able to sell me three sets of springs that would fit the disconnectors - 15 lb, 13 lb and 11 lb.
The 13 lb springs resulted in a 3 1/2 lb pull in semi-auto mode, a 2 1/2 lb pull for the first release in echo mode and 5 1/2 lbs for the full pull to set the release for the second shot in echo. So far my range tests indicate it is reliable.

Interesting. How much did the springs cost you?

yes very interesting , does this distributor have online ordering or will they take a phone order and ship them ?

I did a function check after installing the Echo II trigger lock with the original modified bolt carrier and appears to function perfectly. Will try it at the range this weekend and if it works I'll have a spare bolt carrier... Anyone tried this yet?

Do you have part numbers for the three sets of springs?

Ordered the new trigger lock, so I'll see how that goes.

So is the Fostech Echo II safe to order? Are people having problems still? What's the word?

The company is Leeco in Houston. The guy to talk to is Matt. I do have the part numbers - Matt asked me to keep them handy just in case you wanted to call. I have to find my notes. I'll post tomorrow.

I paid a little extra to Matt for his help. They typically sell in large orders so he broke open packs to sell me two small springs of each weight. I gave him $20 for six small springs. I don't know what he will charge you. Honestly I think the springs probably sell for 50 cents each if you can find the right supplier.

The company that sold me the springs is:
Leeco Spring International
714 E Burress St.
Houston, TX  77022
P 713-692-6281

Salesman:
Matt Couey
[email protected]
www.leecospring.com

Part numbers:
8AB023-6E/M   15# springs
8AB023-6E/S    13# springs
9AB023-6ES     11.5# springs

I'll try to write up a description of how I made the slave pin and disassembly/assembly of the trigger group.  That may be a day or two.

Thanks.  I think I'll give them a call sometime.

Let us know how that call goes.

Are you going to let us know what pull weights you have with the other springs? I'm curious to know how much up or down it would be.

The 13 pound springs sound perfect for pull weights. Factory semi isn't bad but honestly the echo mode sucks big time.

I still haven't ordered an H buffer yet but I think I'll order the new parts to change the echo over to a gen2.

I've written up instructions on how to change out the disconnector springs.  Unfortunately, as a newbie, I am not permitted to exceed 2000 characters in a post.  And the instructions are much longer than that.  Any ideas how to do this?

You can email them to me and I'll post them.

jaqufrost at gmail dot com

Thank you, sir. Will do.

I just emailed the instructions on how to replace the disconnector springs in the echo trigger to jaqufrost.

That being said, "HOLD THE PRESSES!"

I just experimented with changing the "hammer hook" spring - that is the hook at the rear of the trigger group that is held in place with the pin and tiny c-clip. That spring under the hook, small as it is, is a 182 lb spring!  

Leeco had a spring in stock that I installed under the "hammer hook."  It results in an extremely light semi-auto and echo mode trigger pull.  I will test it but I believe it is far too light to be safe and reliable.

Hey, $25 seems reasonable at least. Think of how many Echo Gen 1's they sold, now imagine having to replace for free, every single one with a part that probably costs them around $20 to make (R&D, overhead, startup costs on the new part, etc)

Well... I ordered a gen 2.. Will be my first experience with a binary trigger! Hoping all works out

Sorry this took so long. Here are the instructions from elalto

I am going to try to explain, as best I can, the procedure for changing out the disconnector springs on the Fostech Echo Trigger.You will need a piece of ¼” aluminum or steel rod.  I had a 36” long piece of aluminum rod I picked up at Home Depot for another project, so that’s what I used.  Aluminum is easier to work with because it is soft.  Steel would make a better, longer lasting slave pin.  But the aluminum worked fine.  You will also need a 5/32” drill bit and a drill.  And you will need a 5/32” punch or drill bit shank or in my case, a Geissele trigger pin tool to be used to facilitate working the slave pin and the disconnector sleeve through the trigger housing.  It will make aligning the slave pin and the disconnectors in the trigger housing much easier since the disconnectors are under spring tension.  You will also need a nylon tipped hammer, brass hammer or non-marring hammer.  I use a small gunsmith hammer.The disconnectors and the hammer are held in the trigger housing on steel sleeves.  The outside diameter of the sleeves is .249”  I cut a 4” piece of the ¼” aluminum rod and chucked it up in a hand drill.  I used a small sanding block with 180 grit paper and a file and turned about 2” of the end of the rod down to .247”  I used the file to square up the end of the rod and put a good chamfer on it.  The chamfer will facilitate pushing the slave pin through the disconnectors.   I then cut off a piece of my turned down rod at a little over .5”  Then I used the file to file the cut end square and bring the total length to .5”  Then I drilled a 5/32” hole in the chamfered end .18” to .20” deep.  You can insert your 5/32” drill shank, punch or Geissele trigger pin tool into this hole to aid in aligning the slave pin (or the sleeve during reassembly) through the trigger housing and disconnectors.  It takes a little finagling to guide the end of the slave pin and sleeve through the disconnector holes as you push and tap it through with a nylon tip hammer.Okay, here we go.  The Fostech trigger assembly is out of the rifle.  The hammer block and its spring are not assembled to the trigger group.The first thing to do is exactly what all the youtoobies and Fostech tell you not to do.  You are going to pull the trigger.  Take a picture of the orientation of the Hiperfire springs on the hammer so you can put it back together correctly.  Hold the trigger group in your hand with pressure on the hammer, tweak the hammer block cam until it unlocks the trigger and pull the trigger to release the hammer.  You control the hammer to prevent the Hiperfire springs, guide rods, pin and shoe from taking flight.  It’s easy.  Remember how they are assembled.  The guide rod stirrups must be oriented correctly on the pin that goes through the hammer to prevent the spring set from binding when you reassemble.  Set them aside.The hammer now hangs limp.  Slide the hammer sleeve out of the trigger group frame and set the sleeve and hammer aside.  Remember the trigger pin clips, or “keepers” on the sleeves are oriented on the right side of the trigger housing.Now the fun part.  Take a picture of the trigger group so you can reassemble it correctly.  Take the slave pin with the chamfered end against the disconnector sleeve on the left side of the trigger housing and tap it in with a nylon hammer.  Remember the factory disconnector springs are 32 lb each.  Take your time and gently (or firmly) tap the pin through the outer housing, inner disconnector housing, and each disconnector.  Applying pressure downward on each disconnector to try to compress its spring may help.  The springs are tight and this is the most difficult part.  You will reach a point when the disconnector sleeve can be pulled from the housing with your fingers.  Insert your guide tool into the hole in the end of your slave pin and apply pressure up or down or left or right to align the end of the slave pin with the holes in the disconnectors and the inner disconnector housing while applying force on the other end of the pin to push it through.  When you have the slave pin through the disconnectors and supported in the holes of the inner housing, the disconnector/trigger group can be easily lifted out the rear of the outer trigger group housing.Take a picture of the orientation of the disconnectors.  They are not interchangeable.  Apply downward pressure on the disconnectors to compress the springs and push the slave pin out.  Release the disconnectors slowly.  Insert one of your reduced power springs in the hole of the disconnector and the corresponding hole in the trigger base, compress it and slide the slave pin in part way to anchor it.  I started with the left disconnector, which is the semi-auto disconnector.  Insert the other reduced power spring in the other disconnector and the trigger base, compress it and slide the slave pin all the way through to the other side of the housing to lock the disconnectors in place.  It’s much easier this time because you are installing much lighter springs.Slide the trigger/disconnector group back into the outer trigger group housing.  Insert the disconnector sleeve from the right side and push and tap it through.  You may need to insert your alignment tool into the sleeve to help work it through.  Apply downward pressure on the disconnectors; compressing first one spring and then the next as you work the sleeve back through.  You will push the slave pin out the left side of the housing.  Use the alignment tool to work the sleeve through the holes and reassemble the disconnector/trigger group to the main trigger housing.  Remember, the trigger pin clip on the sleeve goes on the right side of the housing.Reassemble the hammer in the housing and slide the hammer sleeve in.  Remember, the trigger pin clip on the sleeve goes on the right side of the housing.  Reassembling the Hiperfire springs is a bit tricky.  Clamping the trigger group in a vise or other holding fixture makes it a little easier, but not absolutely necessary.  Place the spring guide rod shoe (or base) in its cradle in the trigger housing and the spring rod yoke pin in its hole in the hammer.  The springs will compress against the flat side of the guide rod shoe/base.  Pull back the hammer as if to cock it and place one of the spring/guide rod assemblies in place.  Make sure you have the guide rod yoke oriented properly on the pin to prevent binding.  While holding pressure against it to keep it in place, place the other spring/guide rod assembly on the other side.  When it’s all lined up correctly, cock the hammer, compressing the Hiperfire spring set.  Don’t pull the trigger.That’s it.  From this point, the installation in the rifle is as described in the YouTube videos.

Any update on testing the safety?

I have a Spike's full auto bolt carrier and a Gen II Echo.  I can't get the upper to close, it looks like the carrier is hitting the trigger lock.  How did others get this resolved?

Are you pushing the trigger lock in after letting the hammer down and locking it back by holding the trigger all the way back?

Yep.

Sounds like your going to need to fit the bcg with a file or try a different bcg.

I had the wife pull the trigger lock forward with some dental floss. That allowed the upper to close!  I think I'll try running it this way and see if stuff doesn't "wear" in.

Good plan?

When you pushed the trigger lock forward and held in place by holding the trigger, was the trigger in echo mode?  That's the only way I can get my trigger lock in the forward enough position to close the upper.

Yes.  Either the Spike carrier is too long or my CMMG lower is a little off, or my trigger pack is extra tight.  

This is my first trigger of this type, so I wasn't sure what normal is.  I hope to test it tonight and see if it functions.  Cycling manualy functions fine, so fingers crossed.

I had the same problem. Push the two parts together and in echo mode, SQUEEZE the trigger. Push the hammer lock again and SQUEEZE THE TRIGGER AGAIN. Felt like i was putting 25# of pressure pulling the trigger.

First off, I'm new here so hello!  The referenced post contains the only picture I've been able to find of a gen 2 trigger lock that resembles the one I received.  There may be others in the thread, but it looks like photobucket is having issues.  My understanding was that the only portion of the trigger lock that was changed was the top, however it looks like the "spur" at the bottom which interfaces with the rest of the trigger assembly has been removed and some extra metal removed.  Here are a couple of pictures showing my gen 2 and gen 1 trigger locks side-by-side:




Looks like I have to split this post up because of the new user character limitation.  More to follow.

My primary concern is that on my gen 2 the caliper reads .31mm of metal left at the narrowest point where the selector hole was drilled.  That area will experience stress as the bolt carrier slams the top of the lock forward.  I contacted Fostech and sent them pictures, but without going into too much detail they said the part looks right.  Am I the only one who thinks that's a little thin?

By the way the caliper measurement was taken between the inside of the hole and the outside of the lock in case it wasn't obvious.  I don't know, maybe it's just the nerd in me and my whole post is really just about a non-issue.

LEECO had a spring in stock that was the correct size to replace the "hammer hook" spring (the 182 lb/in rate spring).  Unfortunately, the one they had on the shelf was 27 lb/in, but I tried it anyway to see what would happen.

I put the 13 lb/in disconnector springs in with the 27 lb/in "hammer hook" spring and I ended up with:  2 lb trigger pull in semi auto; 1 1/2 lb initial pull in echo mode and a 2 1/2 lb full pull in echo.  I decided this was just too light.

I installed the 15 lb/in disconnector springs with the 27 lb/in "hammer hook" spring and I ended up with a 2 lb trigger pull in semi auto; 2 1/8 lb initial pull in echo mode and a 3 1/2 lb full pull in echo.  I took it to my local indoor range that allows full auto for testing.

Semi auto functioned okay, but a 2 lb trigger for a defensive or "battle weapon" is just too light.  It would be fine for a target or DMR, but this trigger is just not precise enough to be used for that.  A Geissele or other good trigger would be superior for that application.

My first pull in echo mode resulted in a four round burst as soon as I touched the trigger.  I believe the recoil/bolt bounce/hammer bounce and lack of sufficient spring tension in the "hammer hook" to retain the hammer for a reliable binary function makes it unsafe.  The "echo" or binary mode would not function properly.  No positive control.  Not safe.

I have searched numerous spring distributors and manufacturers and I can't find an "off the shelf" spring in the 100 lb/in range.  I contacted LEECO and they are manufacturing some springs for me in rates that I hope will work.  Lead time will be two weeks.  They have to order the steel wire in the diameter that should be right.  They are working with me on the material and set-up cost, but it is still relatively expensive.

I will post again as soon as I have a chance to test the new springs.  Until then.....

adios, Amigos!

Thanks!

this is getting very interesting. Thanks for your hard work on it. Did you shoot the ECHO with the 15/13 lb disconnector spring and the ECHO hammer spring?  Or did I misread the post wrong?

Yes, Sir.

I first tried the Echo Trigger as delivered from the factory.  The semi-auto trigger pull measured 6 1/2 lbs on my trigger pull gauge.  The initial pull in echo mode (the first release of the hammer) measured 5 1/2 lbs and the "full pull," or the pull to the rear that resets the trigger (a distinct "click" can be heard and felt) that sets the system to release the hammer as soon as the trigger is released measured over 12 lbs (I don't know exactly how much because my scale tops out at 12 lbs.)  Pete, at Fostech, told me that the only weight that was out of spec. is the 12+ lbs.  He suggested I send it back and they would look at it.

I took it to the range and it works just as designed.  The semi-auto mode is manageable, but a bit heavy for my liking.  I would prefer somewhere between 3 1/2 and 4 1/2 lbs in semi-auto mode.  I could dump a 20 round magazine in less than two seconds in the Echo mode.  But the trigger pull is so heavy it was difficult to keep the gun on target.

I found that replacing the disconnector springs with 15 lb or 13 lb springs does reduce the pull in both semi-auto and echo mode.  But replacing only the disconnector springs will only get the "full pull" in echo mode down to about 5 1/2 lbs.  I tested them and it does work.  However, it's still a bit heavy for my liking.

I am trying to get a 4 to 4 1/2 lb semi-auto pull and a 4 to 4 1/2 lb Echo mode.  LEECO Springs has designed a spring for me.  It should be ready in two weeks.  We have no way of knowing if it will work until we test it.  And I will post it up here as soon as I do.

Thanks for doing all this testing and reporting back!  I shaved my bolt carrier, so my semi-auto pull is down to 5.5 lbs, but my full pull is off the chart.  :(

I was contacted this morning by LEECO.  The custom springs are ready.  I will pick them up Thursday and will try to test the new springs this weekend.  I will post the results as soon as possible.  The new "hammer hook" springs are 100 lb/in rate.  That will hopefully hit the sweet spot in reducing the Echo "full pull" and still reliably catch and retain the hammer for the second shot in Echo mode.

Thank you sir let me know where to send money

awesome , looking forward to hearing how it goes