I have a new Beeman QB2 rifle and having a firing of sorts problem. First I only loaded one live CO2 cart and a used one in the front as I always do when first checking out a similar rifle. I was able to shoot about 10 shots, sighted it and then the problem appeared. It would only fire a small CO2 discharge and then logged a pellet near the end of the barrel. Cleared pellet out and without loading a pellet it would only discharge about 1/2 of the time and always very little out at the muzzle. Just in case the cart was empty I found that the fill cap couldn't be turned by hand and with a rag and channel locks I turned the cap about four or five turns. From past experience I knew better to try removing the end cap with CO2 still inside. I tried to keeping working it hoping on emptying it, no luck so far. Any suggestions? I don't want to return it and Would like to solve the problem with your help. Charles
N/A QB2 problem!
- Thread starter sekiar
- Start date
it sounds like a hammer spring problem because you should be able to empty the rifle by just cocking and firing
the why is unknown
the cap should leak and stay on as you get to the end of the threads
could it be the valve but i would guess it isn't
hammer opens the valve and that is not happening
the why is unknown
the cap should leak and stay on as you get to the end of the threads
could it be the valve but i would guess it isn't
hammer opens the valve and that is not happening
Upvote 0
Try removing the action from the stock and putting it in the freezer. Cooling it off may free things up enough to let it discharge the rest of the gas. If it's below freezing where you live you could set it outside for a while. It will reduce the pressure within the rifle.
It sounds as if something is interfering with the hammer-blow to the valve.
J~
It sounds as if something is interfering with the hammer-blow to the valve.
J~
Upvote 0
I did put it out side at abt 40 degrees and left it for an hour. No change so I’ll put it in the freezer tonight and tomorrow give it a try . Thanks to you both! Charles
Upvote 0
Hey Charles,
Sorry forty degrees didn't work. Try to get it as cold as you can. Here's a chart on co2 pressures at different temperatures.
I've found that when using only one cartridge, it's best to insert two full ones with both of them pointing to the rear. That way the second cartridge isn't pierced and its full volume is taken up in the plenum. One cartridge used that way gives me forty useable shots instead of about twenty with an open empty.
Cheers,
J~
Sorry forty degrees didn't work. Try to get it as cold as you can. Here's a chart on co2 pressures at different temperatures.
I've found that when using only one cartridge, it's best to insert two full ones with both of them pointing to the rear. That way the second cartridge isn't pierced and its full volume is taken up in the plenum. One cartridge used that way gives me forty useable shots instead of about twenty with an open empty.
Cheers,
J~
Upvote 0
I now have it in my freezer and if that doesn’t work can I remove the back trigger housing screw and get the hammer spring out even with CO2 still in the gun?
Upvote 0
Cock and fire it a bunch once you get it out of the freezer. That "should" complete the degassing process. They usually fart loudly while doing it.
Cautionary tale. - Back in the day, I had a QB77 lock up and refuse to discharge on a hot day. So I put the action in a vise and took it apart. The valve blew out one end and the tube went the other way. Luckily the tube went into a laundry basket, and the valve just missed me. Lesson learned. (Tim McMurray laughed like mad when I told him about it, then told me I was an idiot and that I should have frozen it and then fired it.) The ruined tube became the first bulk-fill extension ever made for that series.
Were your gun mine and the freeze, cock, and fire method didn't work... I'd re-freeze the gun to reduce internal pressure as much as possible, then pull the trigger group off, then remove the receiver and return the upper valve-screw to its place as quickly as possible. Once that was done I'd use a rod and mallet to tap the valve-stem until the gun was empty. I'd also secure the transfer port seal, because it will fly away when gas goes through it.
I love these things, but I haven't seen a new one with all the screws properly tightened in quite a while. I did a complete write-up on mine and posted it to another board. If you want, I'll DM you a link to it.
Luck,
J~
Cautionary tale. - Back in the day, I had a QB77 lock up and refuse to discharge on a hot day. So I put the action in a vise and took it apart. The valve blew out one end and the tube went the other way. Luckily the tube went into a laundry basket, and the valve just missed me. Lesson learned. (Tim McMurray laughed like mad when I told him about it, then told me I was an idiot and that I should have frozen it and then fired it.) The ruined tube became the first bulk-fill extension ever made for that series.
Were your gun mine and the freeze, cock, and fire method didn't work... I'd re-freeze the gun to reduce internal pressure as much as possible, then pull the trigger group off, then remove the receiver and return the upper valve-screw to its place as quickly as possible. Once that was done I'd use a rod and mallet to tap the valve-stem until the gun was empty. I'd also secure the transfer port seal, because it will fly away when gas goes through it.
I love these things, but I haven't seen a new one with all the screws properly tightened in quite a while. I did a complete write-up on mine and posted it to another board. If you want, I'll DM you a link to it.
Luck,
J~
Upvote 0
Since it doesn't deliver any output when the trigger is operated and I'm leaving it in the freezer tonight and tomorrow it's going outside and I'm going to remove the fill cap and aim it at a tree. Safety glasses and crossed fingers
Charles
CharlesUpvote 0
Out of the freezer and outside in about 34 degrees and slowly unscrew the fill cap and near the end it slowly emptied. The cart only had a very small hole in the end? Ideas appreciated where to go from here? CharlesSince it doesn't deliver any output when the trigger is operated and I'm leaving it in the freezer tonight and tomorrow it's going outside and I'm going to remove the fill cap and aim it at a tree. Safety glasses and crossed fingers
Upvote 0
Glad that you were able to discharge it, Charles.
Something is interfering with the hammer striking the valve-stem in that rifle. It could be a broken spring or something loose inside. You're going to have to pull it apart to see.
Have you done a search to see if others are having the same problem?
J~
Something is interfering with the hammer striking the valve-stem in that rifle. It could be a broken spring or something loose inside. You're going to have to pull it apart to see.
Have you done a search to see if others are having the same problem?
J~
Upvote 0
The baseline symptom is a match to marflow’s comments about a weak hammer strike. In the short time it worked, did you notice anything about the cocking effort that would give you a clue something changed? As in it started getting easier to cock? Or if you cocked it 10 times, does the pull feel the same each time?
Another potential cause is something obstructing the hammer from striking the valve stem. For example if a pellet or a lead fragment managed to fall into the tube and is now between the hammer and valve stem, the hammer can’t open the valve fully.
The last thing that comes to mind is the valve stem pushed through the poppet. I’ve never encountered this type of failure on a QB but they have used both interference fit and threaded connections over the years, and although my experience says the likelihood is small, it’s not zero.
Upvote 0
I've found similar post of similar problems but not quite like mine. Tomorrow I'll take it apart and see what I can find. All of your help is greatly appreciated, and I'll report my findings. Charles
Upvote 0
Here’s what I got out of the action after taking it apart. Not sure where it all came from but now it’s seems just fine. And again thanks for heading me in the right direction! Charles
Last edited:
Upvote 0
what's really strange I've been shoot several differ models based on the QB78 rifles on and off for over 20 some years and 7 now and never had a similar problem with any of those. Is it possible that the factory tested the gun and let some pellets drop in to works during testing, It was probably me that caused it ,however I don't see how it's possible. Since I only shot it a few times I don't hardly see how I could lost that much lead in the action. The only pellet That didnt' exit the barrel and I removed it with a cleaning rod. Charles
Upvote 0
Charles,
I wouldn't be at all surprised if it came that way from the factory. The last few of the series that I've dealt with (ie - straightened out) have not had a tight screw on them. Not to mention the sharp edges and tranfer-port burrs. Then there's the crushed and much restricted transfer port seal. The .22 that I have became a project when all of the above was noted. It wasn't achieving the advertised velocity, either. The originals that Tim had imported were made to a much higher standard. My goal has been to bring it up to that standard.
I'm glad to see that you've got yours working again. Have you cleaned the barrel, yet? They're usually filthy when new and have to be thoroughly cleaned.
Cheers,
J~
I wouldn't be at all surprised if it came that way from the factory. The last few of the series that I've dealt with (ie - straightened out) have not had a tight screw on them. Not to mention the sharp edges and tranfer-port burrs. Then there's the crushed and much restricted transfer port seal. The .22 that I have became a project when all of the above was noted. It wasn't achieving the advertised velocity, either. The originals that Tim had imported were made to a much higher standard. My goal has been to bring it up to that standard.
I'm glad to see that you've got yours working again. Have you cleaned the barrel, yet? They're usually filthy when new and have to be thoroughly cleaned.
Cheers,
J~
Upvote 0
Yes the first thing I did was to clean the barrel. And was it every so dirty. However the outside of the gun was very clean of oil or grease. Most of my similar QB were dirty all over. Charles
Upvote 0