Disco trigger problems

[thumbs]

Last time out I had a problem with an unintended discharge.  Not a negligent discharge.  I was just shooting targets when all of a sudden when I cocked the rifle and moved the bolt forward the rifle went off.  I was in a safe area and had the muzzle in a safe direction so I tried it again thinking I did something wrong.  It did it again so I packed up.  I decided to try to figure what was goin on and to get some info to tell you guys. 

Ok filled the rifle up and loaded a mag.  I cocked the rifle and it was fine.  Shot it when I wanted no problem.  I did this three or four time with out a problem.  After about the fourth time when I cocked the rifle and started to move the bolt forward the trigger fired.  No projectile was launched just the trigger fired as the bolt went forward.  I removed the pellet from the breach and tried it a couple more times.  Same thing.  It feels like the sear isnt getting enough bite to hold the trigger from firing.  I tried it a couple more times what the same results each time..

Ok what are our thoughts as th to problem and the repair.  I have not taken the rifle apart to even look at it.  Is this a normal thing that happens after a lot of use?  Do I just replace the trigger?  Of course I have to take it apart to really see but has anyone else had this problem and what was the cause?

thanks

[BC81]

Does it have the standard trigger unit? Sounds like the safety spring is getting weak and not locking the sear up tight. They usually won't even cock if the safety is out of the housing.

[thumbs]

Does it have the standard trigger unit? Sounds like the safety spring is getting weak and not locking the sear up tight. They usually won't even cock if the safety is out of the housing.

Yes the trigger is bone stock.   Is there a way to test the safety and or repair it?

[BC81]

Remove the safety by slipping a small Allen key or flat blade in the slot behind the trigger and pull the safety spring forward til the safety will pop out. Take the stock lug screw out. Pull the action out of the stock. Open up the trigger housing slowly. Now you can access the trigger guts. I would take that safety srlpring out and give it a little more bend to tension it up and put it all back together and test a few times til you know it's right. If it's broken or something you will need to get a new one from crosman. Only other thing I can think it is the sear is broken.

[thumbs]

Yeah,  I hope thats it.  I really dont want to put much in it.  I put way to much in it when I got it.  It was a fun project but not as they say a tack driver.  I'll take a look at it in a day or so.  Tied up for a while.  Would like to get her up and shooting though.

Just remembered something.  I tried something when testing.  I cocked the bolt and held it back then put the safety on, closed the bolt and it was fine.  I could then fire the shot as normal.  I did that a couple of times.  Cant remember if it held every time or not.  May have to try that one again.  Maybe it is the safety.

Nope went off with or without the safety on.  I do hear and feel a clicking as I pull the trigger though about half way through the pull.
No air is expelled when I pull the trigger though.

Stay tuned. LOL

[threesuns]

you say your Disco has a clip? wonder if any other mods done. 2 & 3 screw trigger mods are common & easy to do.

[thumbs]

Ha a lot of mods when I got her.  Could have bought a Marauder for the same price.  It was fun though. Let me see if I remember.

Multi shot receiver.  Uses Marauder magazines.
Valve mods  cant remember exactly what.
Shrouded barrel.  Quiet as a mouse
Brass hammer spring adjuster.

Didn't touch the trigger.  Not great but its ok.  Or at least was. 

I bought her new a few years ago.  Maybe 2015 wish ?? I was on my way to hunt prairie dogs when there was serious talk of a ban on shooting in the prairie beached of fires so I picked up the Disco knowing next to nothing about PCP stuff. Turned into kind of a project gun.  If I didn't have so much money and time in it I would probably just let her sleep in the corner somewhere.  Bugs me it isn't right so I gotta try to get her back. LOL

[BC81]

It'll be an easy fix and cheap for the parts. That spring is probably 2 bucks from crosman, sear maybe 6 bucks. If that's it. I'm betting on the spring has just lost some tension and can just be bent a little on one end to get it back to locking up. Basically that spring rides on the back of the safety crossbar to tension it, and the other end rests under the sear. If the safety button isn't in the housing it won't latch the sear under the hammer. I doubt the sear tooth has worn down enough to not lock up, doubt it's broken either. I have heard of them breaking but only when they've been used with an Mrod trigger not spaced correctly.

[BC81]

Here is a good picture and diagram of the trigger assembly

[thumbs]

Thanks I appreciate the help again.  I guess I may have to put those things on the back burner and look at the Disco tomorrow. LOL
Things that aren't right bug me especially this stuff.  Do you see any reason I have to degas to do this.  I would think not.  I have a degassing tool around here somewhere but it got away from me.  Not sure exactly where it is.  It may be an easy find but probably not.

[BC81]

Here is a good picture and diagram of the trigger assembly

When you're in there, you should add the 2 or 3 screw mod. Those little bosses on the back of the housing are actually meant for the screws. 2 4-40 set screws about 1/2" long will thread right in those holes. You can add another screw to the front of the housing under the cantilever. Just drill a small hole in the center of the housing in front of the trigger guard and it will let you adjust the sear engagement. The other 2 screws control over travel. Will make it feel like a 2 stage trigger if set right. Also, add a ball point pen spring in the trigger and toss the stock trigger spring. You will get alot better accuracy this way. Doesn't cost buy a buck or so for those screws and a few minutes of your time.
There is a write up on her from RSterne describing it in full detail with pics. If the search button doesn't bring it up, Google it and it'll pop up under discovery 3 screw mod.

Good luck, hope you get it fixed! The disco is still one of my favorite guns to shoot!

[thumbs]

Here is a good picture and diagram of the trigger assembly

Thanks for the picture.  Never got into the trigger so not a clue how they had it setup.  It feels like something is clicking over something in there.  Could be as simple as a loose trigger housing screw allowing parts to skip past each other rather than working properly.  Hope I can get it workin.

I like it also.  The think I dont like is the shroud being so long.  She's a pretty long rifle now. Quiet as a mouse fart but long.  Haven't measured her but maybe 46 47".  The shrouded barrel added about 6" to her.  Didn't really like that much.  The receiver is smooth as glass.
Oh what the heck.  May as well if Im in there. LOL  Story of my live. LOL Never ends. Ha.

[BC81]

Nope, don't have to degass. Just make sure it's not cooked which obviously it doesn't do right now lol. Remove the 8-32 trigger frame screw and stock lug and the whole assembly pops off. Then remove the 3 side plate screws and you're inside.

[Pellethuntr]

I'm thinking you have a worn out sear which is a cheap and east fix. The Discovery is a good gun, I have shot the heck out of mine with very little problems.

Let us know what you figure out!

[thumbs]

Ha now I'm gettin into it. LOL  I haven't been in there since I did the mods shortly after I got her.  I know there is a trick to the safety trigger removal.  That thing you were talking about earlier.  My bench is a total disaster.  Gotta get some room on it to work.  May take half a day.  Oh well its gotta be done anyway this just speeds the process a bit.  It I see anything in the trigger area I'll take a picture and post it.  May as well do soup to nuts while I'm here.

Hey while I have a couple of Disco guys here let me ask ya a general question or two.  I have a ton of .22 Corsmen 14.?? domed.whatever they ares.  I would like to use them.  I have boxes of them.  Anyway what velocities are you guys shooting and what is your shot count? 

Oh yea another mod.  A brass hammer spring adjuster. LOL  I looked you signature.  Always wanted to learn 3D printing.  I was hoping to find a class locally like at the high school.  Nothing big deal just to make some simple parts for other hobbies.  Yeah other than a slow pressure leak I this is the first problem I have had.

Do you mean a worn out sear?  Could be something is wrong for sure.

[Pellethuntr]

Hey while I have a couple of Disco guys here let me ask ya a general question or two.  I have a ton of .22 Corsmen 14.?? domed.whatever they ares.  I would like to use them.  I have boxes of them.  Anyway what velocities are you guys shooting and what is your shot count? 

I shoot 14.3 CPHP's. I get 16 shots from 885-915 but my gun is a bit wonky (I had it modified to a .30 caliber at one point) and probably wastes some air.

I looked you signature.  Always wanted to learn 3D printing.  I was hoping to find a class locally like at the high school.  Nothing big deal just to make some simple parts for other hobbies.

I do machining, CAD and 3D printing work. Send me a message if you ever need anything. I started doing it for a living at the start of this year and it has been a rewarding and challenging experience so far. Thankfully I have a lot of hobbies with online presence and I've made a lot of friends that have supported me.

Do you mean a worn out sear?  Could be something is wrong for sure.

Yes, fat fingers. I edited it.

[thumbs]

Ha yeah I went back to read it again and it was changed.  Another hobby is RC aircraft.  Nothin special just scratch built foam planes electric powered.  There are times I wish I had a small 3D printer.  Example motor mounts camera mounts stuff like that.  Anyway dont want to steal my own thread. LOL 

Anyway according to my notes I think I was getting about 20 shots per fill with the 14.3 domes.  Don't know the FPS though.  So 20 to 25 shots is kinda "normal"??

[BC81]

Standard disco on a 2000 psi fill will get 20 shots in its curve around 21-22 fpe with those 14.3s
Mine is tuned 3200 psi with heavy hammer spring, adjustable hammer, and a 16 inch barrel with an 8 Baffle shroud. Gets 28 fpe with 18.21 grain baracuda hunter pellets for 22 shots down to 2000 psi. With the 24" barrel it was close to 40 fpe but I didn't like the long look with a TKO hanging off the front, and it didn't quiet it down enough.

Here's a pic

[BC81]

Sorry here is the pic lol

[thumbs]

Again just picked here up after quite a while so nothing is written in stone.  I looked at a target the other day and she as shooting JSB 18.13's at about an inch at 50 yards.  Is that about ball park?

Another project is my chrony.  The printer went out this afternoon.  Hopefully its the batteries. Always somethin