Help needed with T05 trigger

Joined: September 1st, 2012, 10:04 pm

August 8th, 2017, 12:35 pm #1

Went to put in a second adjustment screw, and I regrettably took apart the safety assembly in the housing. Now the steel insert that goes into the safety lever keeps the two pins from going all the way through the housing.

[/img]
Quote
Share

Joined: September 15th, 2000, 7:59 pm

August 8th, 2017, 1:03 pm #2

I had one apart recently without problems. Make sure that you're trying to put the pins in the right way. I seem to remember that they might be tapered, and will only go in one way.
http://www.pyramydair.com/schematics/rw ... rigger.asp
Quote
Share

Joined: May 20th, 2013, 12:46 am

August 8th, 2017, 2:48 pm #3

Went to put in a second adjustment screw, and I regrettably took apart the safety assembly in the housing. Now the steel insert that goes into the safety lever keeps the two pins from going all the way through the housing.

[/img]
I think trying some assorted 'wiggling and jiggling' around of the parts during reassembly is what's going to do it for you.

Of course you insert one pin at a time. Just to clarify a point, I feel sure that the pins aren't tapered so they can be installed no matter which end of the pin you insert first.

Use your fingers to align the metal and plastic pieces of the safety sliders as closely as possible to their proper position in the housing so there's a clear circular hole all the way through where each pin fits. Align them to the best of your ability, then pull the trigger blade 2 or 3 times the whole time you're trying to insert the pin(s). If that alone doesn't do it for you, you could try inserting a small pin punch through one of the holes before you even start that process, then work on inserting the 'real' real trigger pin through the other hole. You may have to alternately bear down then release some pressure against the rear of the trigger assembly (i.e. toward the front of the rifle then toward the rear) while you're trying to insert the pins because the fit of the pins through the receiver and trigger is a pretty exact fit. However, it sounds like maybe you already have that part of the assembly process figured out.

If you try inserting the front pin first while working the trigger blade and it won't go in, try inserting the rear pin first. Then insert the other pin while working the trigger blade again if necessary.

In some instances I think I actually removed the trigger blade, then operated the sear the blade hits by hand, up and down--up and down, while inserting the pins. Then I reinstalled the trigger blade, spring, and pin.

I think there's a good chance that will get you somewhere. This is assuming you have that stamped piece of metal that fits inside the plastic piece inserted correctly. If the above doesn't work post again and I'll put my better thinking cap on because I'm working from some rather distant memories here. I worked on a ton of those triggers and I know the problem to which you're referring. Once you've figured it out and done it once you probably won't forget again.

HTH.

Quote
Share

Joined: September 1st, 2012, 10:04 pm

August 9th, 2017, 2:13 am #4

Went to put in a second adjustment screw, and I regrettably took apart the safety assembly in the housing. Now the steel insert that goes into the safety lever keeps the two pins from going all the way through the housing.

[/img]
Got the safety in OK by using your method. Then I got the gun cocked. Loaded a round in the barrel and now the sear won't release the piston. I may have put one of those steel plates (the rear one with the tab at 6:00) backwards. Now I gotta figure out how to tear back down the gun without an accidental discharge going off.
Quote
Share

Joined: May 20th, 2013, 12:46 am

August 9th, 2017, 3:10 pm #5

At least you figured out how to get the thing assembled. Good work there. As far as the sear release, I'm having to think on that one a little.

A few things come to mind.

Trigger blade screws: (You don't need to disassemble the rifle to perform this step). You installed new trigger blade screws. They need to be set inward far enough (CW) to hit the trigger rocker-sear correctly or the rifle simply won't fire. The front screw on that trigger blade adjusts the first stage take-up, the rear screw adjusts the second stage let-off. Let's do this safely! With the safety reset, using one finger of one hand to support the rear of the trigger blade so it can't move and cause the gun to fire, try turning the rear screw 1/4 turn inward (CW), then release the safety and try to fire the rifle again. If that didn't cause the rifle to fire, try another quarter turn, etc. Keep track of how many turns you turned the screw so you can put the screw back where it was if that doesn't fix your problem or give you results you like. BTW, I noticed you have two non-OEM screws in the blade. Is that rear screw long enough to actually hit the rocker-sear soon enough? If not, you might need to try a slightly longer screw. In any case, once you get the rifle to fire, you can slowly add some CW turns of the front screw to give you a nice first stage and a crisp second stage, but still with no trigger creep. If you don't get a second stage at all, the first stage screw is turned in too far. Back it out a little and retest until it works right. I tend to think this item is what's actually going to fix your problem.

However, if that fails you may in fact want to disassemble the rifle and re-check the way you have the internal parts of the trigger assembled.

Trigger plates: The way it always made the most sense to me from a functional standpoint regarding the installation of those two flat plates is to have the rounded end of the front plate facing forward (towards the muzzle), and the rounded end of the rear plate facing rearward (towards the safety button). In other words, the two flat, non-beveled sides of the plates would face and rub against each other. However, I never saw an instance where installing them another way caused a failure of a sear to release the piston. In fact, sometimes when I got a rifle with a T05 trigger directly from the factory to tune, the plates would be facing the 'wrong' direction and the rifle would still cock and fire OK. The next new one I got would have the plates facing a different direction and that worked OK too. I'm not saying that facing them in the wrong direction isn't the cause of your problem, I'm just saying I never saw it here. I don't think it's your problem, although I prefer to have the plates installed the way I told you.

Still not working? This may help: You can test for proper operation of the trigger/sear release and the safety while the trigger assembly and the piston are out of the rifle, with the spring totally out of the picture. You'll need to install the two pins into the trigger housing so the parts stay where they belong while you do your testing. Push the rod on the piston straight back into the trigger housing until you feel a very-light 'click' telling you it's in the cocked position (if you don't feel or hear the click, try pulling the piston out of the trigger housing--if it won't come out, yes, it's cocked). Then release the safety, pull the piston straight forward towards you from the housing, and pull the trigger blade. You may need to pull on the piston fairly hard to duplicate the pressure the spring applies when it's cocked. With you pulling on the piston while you pull the trigger blade, the piston should come out of the trigger housing to simulate a 'fire'. If the piston won't come out of the trigger housing during this test, it's not going to work when the parts are installed in the rifle, either. You'll have to figure out what's wrong before you reassemble the rifle.

You didn't install a new mainspring, did you? Having too many coils on a spring might allow the rifle to cock but put it into a bind. That might cause the safety to appear it's in the 'Fire' position when it's pushed forward, when that's not really the case. If the spring is the right length, did you perhaps install any spacers into the piston or onto the rear spring guide? If so, you might need to remove one or more spacers and reassemble the rifle. If you're still using the same spring and guide set-up as you got from the factory (or that worked OK when you you were previously shooting the rifle), and you added no spacers, this item doesn't apply to you.

This is kinda straining my brain and I can't think of anything else to tell you at this point. If I was there I could probably figure it out pretty quickly, but it looks like you're mostly on your own.

Quote
Share

Joined: September 1st, 2012, 10:04 pm

August 10th, 2017, 1:39 pm #6

So I had to tear the action down again. Piston was stuck in the trigger housing with the main spring compressed.

I should mention this is an Umarex Surge. I also put a delrin washer inside the piston before I assembled everything.

Right now I'm checking the arrangement of the two latch plates in the trigger. The plate with the tab at the 6 o'clock position has some slight burrs from the piston shaft, and there's a bevel on the hole's radius. Ed, I know you've had them installed in different directions, but I'm thinking the bevel should be facing the rear so the sear will release. I didn't notice which way I had it in when everything was stuck in place.

I'd rather work on a Rekord right about now.
Quote
Share

Joined: May 20th, 2013, 12:46 am

August 10th, 2017, 6:05 pm #7

I would tell you to reassemble the trigger with the original set-up on the blade, but based on what I saw in your photo, the large screws you installed will now make that impossible. As far as which way the bevel(s) face(s), like I said, I've seen the plates installed in more than one direction and the trigger still worked and the rifle still fired.

There is a way to take the trigger blade totally out of the equation, and I sort of described it already.

Again, use all due caution here!!

OK. You can remove the blade and trigger return spring from the trigger housing by removing the trigger blade pivot pin--I know you know that much. Then, cock the rifle. Turn it upside down so you can see the bottom of the trigger assembly. Find something that will reach down onto the rocker sear, and push on the place where the trigger screws usually push. As the rocker pivots past a certain point, the rifle should fire. If it won't fire when you do that, the problem is obviously not anything to do with the blade or screws.

I can't comment directly on the Umarex model you have because I never worked on one. I thought we were talking about a good ol' Diana rifle. Maybe there's something different about the Surge. Sorry about that.

Oh, wait, I thought of something. The bushing that fits inside the front of the trigger housing should be tapped as far back as it will go into the housing. (Do you see a bushing there or have they eliminated it?)
If it's sticking out too far, I'm not sure if it could cause a binding problem or not. Maybe.

Again, my apologies for any oversight as I really hoped you'd have it working by now. Wish I was there to help. I know I'm not getting paid, but when possible "Will work for smiles" or whatever.

Quote
Share

Joined: September 1st, 2012, 10:04 pm

August 10th, 2017, 6:41 pm #8

This is as far down as the plates will go. Probably tough for you to see it better. Right now something is keeping the rear plate from going down far enough for the piston rod to latch properly.

[/img]

Bushing at front of housing that holds the stock screw in place is in the right position.

I'll either keep trying or just buy a used Gamo I see on Craigslist right now..
Quote
Share

Joined: September 1st, 2012, 10:04 pm

August 10th, 2017, 6:55 pm #9

Went to put in a second adjustment screw, and I regrettably took apart the safety assembly in the housing. Now the steel insert that goes into the safety lever keeps the two pins from going all the way through the housing.

[/img]
I removed the safety parts so they wouldn't interfere with the sear or piston rod just to see if that was the issue.
Quote
Share

Joined: October 21st, 2008, 9:13 pm

August 10th, 2017, 9:07 pm #10

This is as far down as the plates will go. Probably tough for you to see it better. Right now something is keeping the rear plate from going down far enough for the piston rod to latch properly.

[/img]

Bushing at front of housing that holds the stock screw in place is in the right position.

I'll either keep trying or just buy a used Gamo I see on Craigslist right now..
I happen to have one for sale. I do, but seriously what are you hoping to get from your rifle? Power? Accuracy. Quality? Ease of working on?
Quote
Share