Beeman 1085 - CO2 Puncture Problems

[AndyKunz]

Let me preface this by saying I love my 1085.  I changed it to a nice wood stock (from a QB78 Deluxe), found a way to use Marauder magazines in it, found a great 3D printed flexible single tray, and see lots of applicable QB78 information online (much of it right here in GTA, in a book by an unmentionable author, and on several other forums around the globe).  I've worked with Caption O-ring to get a bill of materials together for a 1085 rebuild kit.  It has been a lot of fun.

A few weeks ago I started having a problem with the one CO2 cartridge not puncturing every time.  Now it doesn't puncture at all.  The other one punctures as I tighten the cap.

This thread is not a rant.  I've almost exhausted my options, and wondering if there is something to add to my to-do list.  Here's what I've tried so far:

* I put a dime (or two) between cartridges. 
* I opened the cap 1/4 turn (this is important on my Umarex Ruger 1022, no noticeable difference here)
* I have removed half of the felt, in case it was a cause.
* I polished everything that slides (except the piercing pin itself)

Yesterday I spent several hours polishing everything that moves in the gun except inside the trigger mechanism.  The smoothness now is an amazing improvement, something I should have done before the first shot.  If there was any possibility that the hammer was hanging up, it's not true any more.  I didn't touch the pin yet, though.

I have not:

* Changed from Crosman CO2 (I have another 120 to go ...)
* Ruled out going bulk fill.  I prefer not to.
* Called Mike about working on it.

Things to try tonight:
* Put the full felt back in.
* Polish the piercing pin.

* See if I can find some non-Crosman CO2  (Looking for suggestions for IN STOCK and KNOWN-GOOD)

Helpful threads:
* https://www.gatewaytoairguns.org/GTA/index.php?topic=91832.0
* https://www.gatewaytoairguns.org/GTA/index.php?topic=137730.0
* https://www.gatewaytoairguns.org/GTA/index.php?topic=114228.20

Any other links I should review?  Any more suggestions for things to try?

Andy

[Ribbonstone]

It's sealing...so can only assume the piercing pin isn't piercing.   Would be interresting to know if the bottom 12gr. NEVER gets popped or if it will pop if you loaded a full one and then an empty.

Could be from several things, which you aren't going to solve from the outside.

If it's been way- low-tuned, could be not enough energy to pop the 12gr.

The piercing pin could be dulled...but it would need to be pretty dull (ever load the first one backwards?).
Possible to have it seal and NOT have the front half of the valve screwed down tight...which would make for a real long reach for the piercing pin.
Could be some kind of hang-up inside the valve itself.
Could have removed more than just the fiber filter.  That washer/spacer with a hole in it does seem to help center the piercing pin.

[AndyKunz]

It's sealing...so can only assume the piercing pin isn't piercing.   Would be interresting to know if the bottom 12gr. NEVER gets popped or if it will pop if you loaded a full one and then an empty.

I tried putting in a new one first followed by an empty one.  It doesn't pop it.

If it's been way- low-tuned, could be not enough energy to pop the 12gr.

It worked for a month.  I've lost track of rounds, but certainly close to 1000 if not more.  And getting 100+ shots from a good set of cartridges, that would be 10 times it punctured OK.

The piercing pin could be dulled...but it would need to be pretty dull (ever load the first one backwards?).

No.  And I'd deserve it if I had!  There's a pretty good dimple in the end, just not enough to open it up.  When this problem first arose, I would continue to shoot to drain down the cartridge, but that was getting ridiculous as so little CO2 came out each shot.  That wouldn't be too different than inserting an empty and a full to see what happens, so I'm saying it won't matter.

I hate how using pliers is damaging the cap finish

Possible to have it seal and NOT have the front half of the valve screwed down tight...which would make for a real long reach for the piercing pin.

The front of the valve is screwed down tight.  In order to get the rear O-ring to go into the tube, I have to not compress it.  Then it slides into place with a little help of a push rod.  I then tighten up from the front as advised in Steve A's book.

But your comment gave me an idea.  I'm going to insert two empties and see how far the cap closes to, and compare that to what I get with a new set of CO2.

Could be some kind of hang-up inside the valve itself.
Could have removed more than just the fiber filter.  That washer/spacer with a hole in it does seem to help center the piercing pin.

The washer is still in there, and if I push the valve manually from the rear it opens without jamming.  I can push the hammer right up to the limiter. 

Good thing to check: Does the stroke match the necessary depth to puncture?

Thanks for the questions!

Andy

[AndyKunz]

I have not:

* Changed from Crosman CO2 (I have another 120 to go ...)

Next Wednesday I'll have 100 Umarex cartridges here to try.  I used Umarex once before, but not since I got this gun.  They won't go to waste even if they don't work here.

Andy

[Back_Roads]

 It could be the 12 gr cartridges, with like Crosman, one sometimes has to put a dime / penny in between the carts to get a full pierce.
I have that issue with one of mine , and was in the process of using one cart on one end then the other to see what one was the issue, then got sidetracked 

[AndyKunz]

It could be the 12 gr cartridges, with like Crosman, one sometimes has to put a dime / penny in between the carts to get a full pierce.
I have that issue with one of mine , and was in the process of using one cart on one end then the other to see what one was the issue, then got sidetracked 

Already tried with dimes.  No luck.

Tonight I tore it down again and polished the puncture pin sides, the tip, and the hole it slides through.  While I had it apart I also took some measurements and photographs.  Maybe one of these will suggest something to somebody...

Picture 1 shows two Crosman cans from yesterday.  The one on the left is the second one (inserted second, "front", etc) and the right is the one that goes in first.  You can see a dimple, and the dimple is pretty well centered (not always the case).

Picture 2 shows a close-up to compare the ends of two types I have on hand, a Daisy and a Crosman.  Picture 3 shows the labels just to be sure.

I showed you all those so, if you'd be so kind, you could compare to what you have that works.

Picture 4 shows the depth that the puncture tip goes into the end of the can.  It really is right about 1mm more that it could travel before the blunt faces hit, which I'm sure would give a good hole.

Picture 5 shows what the tip looked like before I started tonight.   I have since polished it up.  I don't think it did much other than to make it shiny, but shiny is nice too.

Picture 6 is something I hadn't noticed earlier.  The spring inside the valve has both ends flattened.  It looks to me like they were ground provide an even pressure between the pin and the valve pin, probably to prevent sidewards motion (and thereby jamming).

Picture 7 is the length of the pin, 29mm.  If anybody has one of these and could compare, I'd appreciate that.

Picture 8 is the valve spring, 20.7mm.  Again, if you have one to compare, that would be great.

Picture 9 is the main spring for the hammer, 59.5mm.  I'm wondering if this isn't providing a hard enough whack.

Next time I have it apart (gotta do some yard work tomorrow, so probably not until after church on Sunday), I will weigh the various parts.  It just dawned on me that that might help generate some discussions.



So, recap on tonight:

* The Daisy can didn't work any better.  I used 1 Daisy, 1 Crosman (because the Crosmans work fine at the other end).
* The polishing on the pin and guide hole didn't help.  Hopefully all the polishing that happened to the air path will help down the road.
* I measured the over-travel of the hammer between rest position and full-forward (which would puncture) at 3mm.  The tip is right at 2.5mm, so it SHOULD be hitting the can right up to its face.  That was why I measured the hammer spring, in case that's not the right length.
* I also cranked the end cap all the way down, using pliers.  I'm going to need a new QB78 new-style (long) cap once I get this figured out...

I appreciate all the views you are all making.  If you have any ideas at all, please comment!  I'm a firmware engineer by trade, and my team has been tracking down a problem that was reported several months ago.  One of the guys managing the project mentioned that somebody made an offhand comment about something he did that caused it to work, and that offhand comment gave us the solution we needed in about an hour of brainstorming.  Every little idea counts!  Your "my ideas never work" thoughts might be the solution for me!  Please share!

Thanks.

Andy

[Ribbonstone]

Made me look.

Taking mine apart,the striker spring is just about the same length as that,and it seems to work for poping both 12gr. with the first try. Am a little suspicious of the open end of the striker you show spring....usually they have a closed/dead end....so that one does look like it's been shortened....but the factory has done that kind of happy-whappy stuff before.

So am thining something elese is going on....but if spacing the spring to add tension to the striker spring works,may as well try it and see.

[Doug Wall]

Sounds like something is keeping the piercing pin from hitting correctly. Compare your valve parts to online pictures, like ones at 4rcher$.

[Ribbonstone]

Does look the same...it's your basic QB valve, pretty much the same valve in the WB78,79 used in the 1085.

Don't know about the valve stem retrun spring you show...haven't measure that on mineand the only other loose QB valve has been modded.

Just to be sure about operation.

Will call the first one loaded in (neck down) as #1 and the 2nd one the one loaded last (neck up).

IF you charge it the way directed, would tighten down the  end cap...hear a little hiss from #2....and back the end cap off a fraction of a turn and hear #2 fill the tube.

Then we cock and fire to pop open #1.

#1never gets a full power piercing pin strike that way....valve stem is working against the pressure created by #2.  The valve movement is a whole lot less that your picture of the pin protuding when it's being held closed by co2 pressure...and in this weather,that can be a lot of pressure.


Little quick math....valve stem seal body is about .37"...works out to about .107 square inches.....so if #2 supplied 1000psi, would be 107 pounds of force holding the vlave closed BEFORE we try and pop  #1.

Usualy it will pop a little hole in #1. 

We don't notice #1 starts with a tiny hole,becasue we don't open it up to look until the gun is empty enough to need recharging.   By that time,it's beaten the hole in #1larger though reptition and lower pressuresas the gas runs down.

So....just to be sure...if you load a live #1 and a dead #2, if it doesn't pop open #1 (at least a little), then you for sure have an issue with striker spring tension or some kind of power robbing  blockage/friction inside the valve.

[AndyKunz]

Your explanation matches my understanding as well.

I haven't tried loading a dead #2 yet.  That's an easy thing to try.

I need a break right now (backfilling behind retaining walls), so I tried it.

HEY, THAT WORKED.  Sounds like we're onto something here!  I'm gonna get rid of a few pellets and see how long this lasts.

Andy

[AndyKunz]

So it did pop the canister open, but it doesn't have any power behind it even after 2 dozen shots. 

I have to get back to work outside now.  I'll take it apart when I'm done.

Either the hole it's making is insufficient, or there is something about the valve that needs fixing.  Maybe the felt is too much resistance?  Or it's not opening all the way?  I don't know, but at least now I have something more to go on.

Thanks for your help!

Andy

[Bentong]

Can you post  a puncture picture of the last cart you used with low 2 doz. shots.

[AndyKunz]

Can you post  a puncture picture of the last cart you used with low 2 doz. shots.

Wow, Leo, you knew just the question to ask!

Here you go.  The hole isn't a hole, it's better to think of it as a minor leak   It actually doesn't open like a hole, it's really just a crack in the dent.  I tried a #79 drill bit (smallest I had) and it doesn't even detect a place it wants to go.  Looking at it under a magnifier, it really is just a crack.

If these aren't good enough, let me know.  I'll try setting up a more formal photo.

Andy

[Ribbonstone]

IF that is #1 with a dead #2...then you either need a bit more striker spring tension or a less strong striker return spring....or just not worry about it.

Could load a live #1and #2,screw the end cap down, and quickly fire to pop open #1 BEFORE you back the end cap off that fraction of a turn.


Seriously...the only co2 a 12gr. running rifle gets to shoot from is whatever co2 is already in the valve....any "refill" of the valve doesn't get there quick enough to make a real difference.

[Bentong]

That poke right there should give you power shots. One way you won't get the desired power is if your TP is restricted. Remember when you showed your oem TP being crushed and replaced it with poly tubing. You cut that too short it leaks and cut it too long and it get crushed.

[Ribbonstone]

There is some weird math to QB's double 12gr.system.

Using one 12gr.,lets say it takes 2 grams of co2 to gas up the tube and the empty 2nd 12gr....leaving 10-10.5 grams of liquid co2 to shoot from.

Popopen two 12gr,and it may only take 1gram of co2 to fill up the tube (beacuse the 2nd 12gr. is not an empty one)...so you have 23grams of co2 to shoot from.

So there is always more than 2X as many good shots from 2X12 than there is with 1X12grams.

[AndyKunz]

IF that is #1 with a dead #2...then you either need a bit more striker spring tension or a less strong striker return spring....or just not worry about it.

Could load a live #1and #2,screw the end cap down, and quickly fire to pop open #1 BEFORE you back the end cap off that fraction of a turn.

Already tried that.  Didn't change anything.

Seriously...the only co2 a 12gr. running rifle gets to shoot from is whatever co2 is already in the valve....any "refill" of the valve doesn't get there quick enough to make a real difference.

While reading up on this last night, I saw a number of valve mods intended to increase the refill speed of the valve.

The first shot is good.  I easily hit my target at 40 yards.  The second and following shots drop 2' on the way to a 20 yard target.  Even if I wait a minute or two, or only 10 seconds, same result.

Andy

[AndyKunz]

That poke right there should give you power shots. One way you won't get the desired power is if your TP is restricted. Remember when you showed your oem TP being crushed and replaced it with poly tubing. You cut that too short it leaks and cut it too long and it get crushed.

I've just been eyeballing that, but I suppose I can measure with a depth gauge and go from there.  Got a suggestion on how much it should be compressed?

But as I just noted, I DO get a good shot at full speed.  Just one.  And then after that one, they're better described as farts than shots coming out of the barrel, whether I wait seconds or minutes between shots.  It would seem to me that they would stay full speed.  I can see that maybe subsequent shots slightly slower due to contraction from the cold, but after warming up in the sun for a minute on a hot day, you'd think it would be back to size pre-first-shot again.  But that isn't happening.

[Back_Roads]

 I do have valve lock issues with one of my QBs when temps get above 85 degrees, I'm thinking more hammer spring to cure that.

[AndyKunz]

Quick question:

The 1085 is a cock-on-open setup (which as I understand is like "the XP mod").

Is there a different order to the way the hammer and springs, etc. go into the tube vs. a QB78? Got a picture showing the correct sequence and orientation?  I had a dream last night that I was putting the gun together backwards.  I never consciously tried putting it together a different way, so it's entirely possible I have it backwards, if it's possible to put it together backwards.  I haven't taken it down since yesterday, and probably won't until tomorrow as today will be grape harvest in my back yard.

Andy