Author Topic: BFS/ ECHO type trigger for your EVO ?'s  (Read 1717 times)

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Offline Asmodeus

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Re: BFS/ ECHO type trigger for your EVO ?'s
« Reply #15 on: September 05, 2017, 01:50:41 PM »
It looks like the ECHO trigger is more stable than the Binary trigger. Sounds cool but not sure if the selector was meant to go to a 3rd position for the S1 model.

The trigger pack housing has a half moon cut and the selector uses a roll pin to dictate it's course of travel.  Simply measure the amount of sweep you need, and trim that out of the pack housing.  The trick will be modifying the safety drum that spans the pack housing and making it drive a second disconnector.  Or, not.  And it will have to have some tricky dynamics where the second disconnector falls back to the first if you flip it off of binary function.  That's the hard stuff. 

If the FCG parts were available at even quasi realistic prices I'd already have one going.

The real trick is probably going to be keying in the FPS arm as a sear trip for added protection of OOB strikes stopping the gun if you get ahead of the lockup. 

There is enough clearance between the release of the disconnector hook of the hammer (with a slight reduction in nose profile) and the trigger hooks catching it to allow the hammer to release and near miss the trigger hooks on release.  A 30-35 thou shim under the disconnector foot is a good place to start.  When shimming to pull out the slop in the FCG you will find this magical zone when you go just a hair too far.  Dry runs proved it will ignite on release as the FPS is still depressed enough at this point of travel to allow the firing pin to strike. 

I'm unaware of the legality - and what is required to ensure you stay out of the grey areas on this subject so I just let it go.  But since it's a dual hook trigger, modifying one disconnector to release so it gets caught, and another hook to not - could give you primary / secondary disconnector function without complicated mechanisms.  Getting the secondary to kick down to the primary (SA) disco is the one I can't think my way through.  Keep in mind the majority of this subject could be used / misinterpreted for another purpose.  But from what I can tell, not reliably, or even remotely safely...





Quite frankly, a binary would be perfect for the little Scorp.  They get going plenty good without the retarded bump fire nonsense junking up the gun.  I don't think making one for the Scorpion would be remotely difficult to do.  But there is absolutely no clarification out there on what keeps it on the right side of the law.  What mechanisms it has to have to prevent Ricky Bobby from removing parts and getting himself in trouble.  I proposed a group think project - to see if we could engineer it, and then just have one of the major companies doing them to pick it up and make it for us.  But, nobody really seemed to bite.  Everyone here has this gun and a pair of eyes.  The pack housing comes out in 10 seconds...
« Last Edit: September 05, 2017, 02:19:39 PM by Asmodeus »

Offline akuser47

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Re: BFS/ ECHO type trigger for your EVO ?'s
« Reply #16 on: September 06, 2017, 08:38:56 PM »
None yet sadly, and we all can only wait to see if there is a manufacturer brave enough to make the investment yet.

Offline Thrillbilly

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Re: BFS/ ECHO type trigger for your EVO ?'s
« Reply #17 on: September 06, 2017, 10:34:34 PM »

Quite frankly, a binary would be perfect for the little Scorp.  They get going plenty good without the retarded bump fire nonsense junking up the gun.  I don't think making one for the Scorpion would be remotely difficult to do.  But there is absolutely no clarification out there on what keeps it on the right side of the law.  What mechanisms it has to have to prevent Ricky Bobby from removing parts and getting himself in trouble.  I proposed a group think project - to see if we could engineer it, and then just have one of the major companies doing them to pick it up and make it for us.  But, nobody really seemed to bite.  Everyone here has this gun and a pair of eyes.  The pack housing comes out in 10 seconds...

I really want to see a binary option for this weapon. I wish I had the engineering knowledge to make it happen.  But, I would be happy to volunteer time and other talents to help pitch a blueprinted prototype or concept to a company that is in a position, and licensed to, manufacture it.

My gut tells me that one of the CZ focused machine shops would be most interested in offering a solution. They have the most experience with the Scorpion firing group, and total market penetration so there would be little marketing outlay required to begin selling them in bulk. Otherwise, an existing producer of AR style systems might take up the mantel.

The market has shown that a price point between $300-$450 is viable. So there is some real incentive to produce a product., even with the relatively small initial customer base. It's a new and exciting platform that is likely to flourish for decades to come. This is quickly becoming "America's favorite Sub-gun". A binary trigger will make the Scorpion a must have, driving sales for both the gun and the part.

« Last Edit: September 06, 2017, 10:41:08 PM by Thrillbilly »

Offline John A.

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Re: BFS/ ECHO type trigger for your EVO ?'s
« Reply #18 on: September 06, 2017, 10:48:12 PM »
I'm pretty sure some of the makers are concentrating on an HK style binary trigger.

For those that know, most of the HK trigger packs are relatively similar in design and that would open up the MP5, Cetme and other guns in the market.

And realistically, most of the people buying the triggers aren't paying $400 for them.

Sure, some did initially when they first hit the market, but they can be found in the used market for around $250-$300'ish pretty easily if you are patient and look around.

I have also seen a guy offering binary's for AK's and the scorpion is very similar to it in many respects, but not exactly.

http://www.akfiles.org/forums/showthread.php?s=2144773f6f9d7ca6efb74c591558e55d&t=316789

video here: https://www.youtube.com/watch?v=UsoJe5-xetg&feature=youtu.be




When people ignorant of guns make gun laws, you end up with ignorant gun laws.

Offline Asmodeus

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Re: BFS/ ECHO type trigger for your EVO ?'s
« Reply #19 on: September 08, 2017, 03:23:43 PM »

I have also seen a guy offering binary's for AK's and the scorpion is very similar to it in many respects, but not exactly.


http://www.akfiles.org/forums/showpost.php?p=4175150&postcount=16

^  Read this.  That is exactly what I was suggesting.  Great minds.  I knew it would work...

That leaves the selector drum / barrel portion just being optimized to drive or not drive the disconnector of your choosing.  On the AK you just swap to a FA selector.  Not so simple on the CZ.  But there is absolutely room for a second disconnector in there.  Pop the trigger top with a drill, there's our spring pocket.  And then fine tune the trigger hook on the each side so it operates properly. 

This could be done with someone willing to EDM some disconnectors, a spacer, and a new safety center section.  (And some hand filing)   

Offline John A.

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Re: BFS/ ECHO type trigger for your EVO ?'s
« Reply #20 on: September 08, 2017, 04:17:26 PM »
I don't really think it's so much as of a matter if it CAN be done, but from what I can tell, the binary trigger makers are both doing so with the addition that the selector can be manipulated so as to be able to fire only a single time.

If you were to try to do this with the scorpion, it would be a dedicated all the time, fire on the pull and the release. 

Also, I'm pretty certain that a new selector would need to be produced.

I'll add this here:

When people ignorant of guns make gun laws, you end up with ignorant gun laws.

Offline Asmodeus

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Re: BFS/ ECHO type trigger for your EVO ?'s
« Reply #21 on: September 09, 2017, 02:33:11 PM »
I don't really think it's so much as of a matter if it CAN be done, but from what I can tell, the binary trigger makers are both doing so with the addition that the selector can be manipulated so as to be able to fire only a single time.

If you were to try to do this with the scorpion, it would be a dedicated all the time, fire on the pull and the release. 

Also, I'm pretty certain that a new selector would need to be produced.

I'll add this here:



How so?  There's room in there for a second disconnector.  You could mount it on the left side and cut the spacer and have two.  The tricky part is getting the selector to pick which one you want to use.  But I think you could simply hit the shaft with a welder and then shape it into a ramp that would push down on a tail that is common in a lot of firearms. 

As stated in his video - the BAFTE didn't like his gen 1 kit.  The gen 2 solved this by running two disconnectors.  It definitely shed some light on the hammer follow of a single modified disconnector as well.  Where they are modified to touch and go, and holding the trigger at the exact right spot allows the hammer to sneak by.  The third gen used a live disconnector that changed orientation based on the pull or release.  Sounds fancy.  No idea how that's happening. 

I think the selector shaft could easily be welded on and shaped to create a ramp to actuate tails on the disconnectors.  I already explained how to get a third position on the selector.  So, in theory you could have primary and secondary disconnectors that allowed normal function, and then pull and release function.  The only thing I can't work out in my head is how much fiddling it would take with the trigger hooks and hammer to make the sides operate independently, but still overlap enough to catch the hammer so there was no hammer follow window. 

I know it can be done.  Simply shimming the (unmodified) disconnector creates the binary function and once it's in the teeny tiny window where this happens, I didn't observe any hammer follow.  That said, I wasn't trying to prove a case, or even create a binary trigger.  Simply see how much slop needed to come out, or if I could get the disconnector to stay away from the back of the hammer to eliminate it's spring stacking into the trigger pull without grinding it back.  It did however prove a 5 thou window exists where the gun will release the hammer on pull and release.  And that was without modifying any parts. 

Offline John A.

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Re: BFS/ ECHO type trigger for your EVO ?'s
« Reply #22 on: September 09, 2017, 02:54:49 PM »
Quote
The third gen used a live disconnector that changed orientation based on the pull or release.  Sounds fancy.  No idea how that's happening.
 

I have a gen 3 in one of my AR's. 

It's not really as fancy sounding as you think.

The disconnector is set up very similar to how an m16 disconnector works , but the selector determines which disconnector is active. 

There is some more stuff going on with the binary disconnector though, especially concerning the spring/cam action.

But an AR binary and a scorpion binary would be totally different.

It would need a lot of work.  Mainly in the proprietary selector lever(s) and disconnectors.

To be fair about it, if you're going that far with it, nothing says that a different style trigger, disconnector, hammer and selector can't be used altogether.  Just because the scorpion currently has an Ak'ish style fire control group, doesn't mean that it would have to remain that way as long as it can drop into the lower receiver.  It could even have it's own drop in housing.

When people ignorant of guns make gun laws, you end up with ignorant gun laws.