Double Set Trigger not Engaging (BRNO) *Help*

[koesdibyo]

I just received a BRNO off a trade. It is my first BRNO, as well as my first double set trigger. (1949' 7x57 with the "butterknife" handle)

When it arrived, I gave it a once over and found that the double set trigger does not engage. Hoping I wasnt traded a lemon, and it was simply something that got jostled in transit, I took the trigger assembly out to begin inspecting.

Below is a video of my findings. When pulled to the rear (rear trigger), the arm with the shelf does not catch under the latch of the front trigger.
However, if I apply pressure to the latch, it will move enough that it does catch with the arm and engage it.

Ive also included pictures.
First is of the trigger pulled to the rear, which applies pressure to "set" the latch to be ready to be engaged.
Second is a close up of the point where the rear trigger arm should be hooking under the latch, but is off by a bit
Third is of the same close up, but with my finger pushing the latch back manually that extra bit, which does give it that ability to engage

*Everything being done is with the set screw being backed out all the way to not interfere at all with it. At the set screw fully in, even with pushing the latch with my finger, it will not engage.

https://vid.me/D2no

Was this tampered with (bubba'd), general wear, or is there supposed to be a spring of some sort to push the pressure upward on the latch that is missing? I hate to think the guy traded me a lemon knowing it... but I cant imagine it had worked just fine before he sent it, and arrived to me like this.

I cant seem to find BRNO diagrams, or parts to be able to compare what the trigger parts are supposed to look like to

 

[farshot]

If I remember I will dig out a BRNO trigger and take a look....but the set screw is a fine setting device. All in and all out may not be sufficient. Try setting the screw in a bit at a time while trying to work the set.

See if the set screw tip is even making contact with the appropriate cross bar piece . Sometimes the set screw is replaced and it is too short or it just misses the cross bar and no set occurs.

 

[koesdibyo]

If I remember I will dig out a BRNO trigger and take a look....but the set screw is a fine setting device. All in and all out may not be sufficient. Try setting the screw in a bit at a time while trying to work the set.

See if the set screw tip is even making contact with the appropriate cross bar piece . Sometimes the set screw is replaced and it is too short or it just misses the cross bar and no set occurs.

That would be awesome. I am almost thinking a flat spring of some sort may be missing to apply pressure on the latch (mimic what I did with pushing my finger)... but I dont see any seating points that it would belong, so it has me scratching my head as well.

I have played with the set screw, and it's length is good. At *almost* full turned in (about 1 turn out since being fully in will not allow the the latch/arm to catch each other at all with using my finger method), it pushes upwards on the bars, and when backed out, there is no resistance - which gives an "easier" means of making the 2 pieces catch.

With the trigger assembly back in the gun. If I pull back on the rear trigger and hold the firearm completely upright (allowing gravity to help the latch go that extra millimetre needed), and push forward on the front trigger (again to help with getting everything positioned correctly) I can get it to engage. When held horizontal, this is is a no-go.
*this is leading me to believe more and more, a simple spring is all that I am missing... hopefully.

Also, if you do remember to dig one out, is the front trigger floppy or still? Mine is floppy... again, thinking perhaps the spring (or lack there of) is the culprit.

 

[AP]

here's an internet pic that shows that this particular DS mechanism (not a BRNO though) has a spring that presses the "latch" up and forward to engage the "shelf" on your excellent pics

unfortunately all the double set triggers I have are anschutz design and my BRNO's are the "single set" type

 

[9.3]

There is a flat spring that should have pressure on the latch so that it springs ahead. It is the almost the same as the mauser system in the photo.

 

[freddygotarf]

2X .you are missing a little spring that pushes up on the piece that cocks the trigger.
It clamps in under main spring using same bolt. I had same trouble with mine. I made a little spring out of an old magazine spring.

 

[farshot]

The piece that I have out of one of my BRNO's only had the rear trigger remaining.

After looking at the pictures above, thos eposters are correct, you are missing the spring parts and screw that is similar to the upper picture.

It is possible to find replacement parts from used rifles. Many thought having a single trigger was better, and therefore had the set function either disabled or replaced.

I have a few BRNOs with either completely replaced trigger groups with only one slot for the one trigger or simply the double trigger housing with one trigger remaining.

It is a hunt and seek proposition however to find the parts.

 

[koesdibyo]

Luckily I do have the main spring and screw as pictured by freddygotarf. I will be trying to replicate that secondary spring that applies the upward pressure and clamps underneath the screw/main spring in that same picture.

How thick is the material from the old magazine spring you used?

 

[Cleftwynd]

If required, let me know and I will take one of mine apart and take pics and measurements for you.

 

[freddygotarf]

I used a mauser magazine spring just like the one you will have in that action.
I think I still have the rest of it left. If you don't find anything to use PM me your address and I'll send you a piece.

 

[kamlooky]

Boy, this thread is sure hurting the brain cells. Been years since I've had my 21H apart.
I'm thinking there should be a z spring in there.
Z .........being the Z grabbed and pulled to elongate it for shape.

 

[koesdibyo]

Had a couple spare springs from ARs in my box of "extras" and decided Id try one of those to see how it fit/work.

Tried to find something with enough rebound, and proper thickness to make the same flat spring w/bolt hole as previous in this thread... but came up empty handed on what I had available.

So far the AR spring works; 4.75 oz pull when set all the way in, and grabs every time.

 

[koesdibyo]

I had an "ahhh ha!" moment.

The AR trigger spring works... but because it sits on the front trigger itself, when not on in a set-trigger mode, it would be a weird pull.

Thinking and thinking about what I had that was spring-like, small enough, and disposable - Nothing. Then it dawned on me, the wife has hair clips

I drilled a hole in the widest part, and cut it to length. The middle tang/spring makes for a perfect cradle for the latch with the legs on either side of it to prevent it ever shifting and falling off the "spring". I left the outside legs, and they follow the contour of the trigger assembly frame perfectly.

All in all, Im happy with the fix.

 

[Cleftwynd]

Creative and well implemented solution!!

Glad you sorted it out!!!

 

[freddygotarf]

thats awsome! It should work just fine.

 

[Raton57]

I will have to check mine now to. My problem is that the triggers are independent to the safety so you can pull them wit the safe on ans then it fires when you take the safe off. Very hard to shoot it that way.