Beeman P3 not locking up

[rbl1949]

I have a Beeman P3 .177 pistol that has started not locking up after it is pumped.  As the trigger is pulled, you can see the rear of the slide lift up slightly from the frame.  This plays heck with accuracy.  I have to keep my thumb on the slide to keep it from raising.  Any thoughts on a fix?  Also, about 1 out of every 30 shots, the gun fails to fire when the safe is taken off and the trigger is pulled.  I have to put the safety back on and keep pressure on the trigger while releasing the safety to get it to fire.  After that, it's good for another 30 or so rounds.  Any ideas on this?  Thanks.

[WyoMan]

Any ideas on this?

Yes, but not any good ideas… sorry, never heard of this problem(s) before and they may or may not be related.

My initial thoughts… you have an alignment/wear issue with parts number SR160 (auto safety lever) and SF090 (safety on/off slide).



How it’s supposed to work…
When the over-lever is down, the compression tube forces the spring-loaded SR160 down, this allows the safety to slide forward into the fire position. When you open the over-lever, the SR160 pops up (from the spring) and pushes the safety back into the safe position. This blocks the trigger.

Check to see if that is working. With the over-lever partially open, you can see the SR160 lever:


While pushing down on the lever (with a pencil eraser or similar) see if you can slide the safety forward into the fire position:


The above picture shows the position that the SR160 should be in when the over-lever is closed. The safety is on “safe” but it can be slid forward to fire.

You can also lube the surfaces and the pivot when you try this. Don’t really know if this will help….

Wyo

[Yogi]

Tom Gaylord over at Pyramid airgun blog is currently in a long review/test of them.  In parts 1 and 2 a guest blogger explained how to fix them.
Check it out.

-Y

[rbl1949]

Thanks for the info.

[WyoMan]

One more thing, and I'm probably just stating the obvious... is your barrel positioned so that it just makes contact with the breech seal upon closing?
If it is too far aft, it can bind on the o-ring and be difficult to close (in theory)... I had that problem with an Alecto when I was adjusting the barrel postion. But they have a very robust barrel clamping setup and can withstand extreme forces. The P3, not so much. So it's not very likely. Just throwing that out there....

Wyo

[Stinger177]

One more thing, and I'm probably just stating the obvious... is your barrel positioned so that it just makes contact with the breech seal upon closing?
If it is too far aft, it can bind on the o-ring and be difficult to close (in theory)... I had that problem with an Alecto when I was adjusting the barrel postion. But they have a very robust barrel clamping setup and can withstand extreme forces. The P3, not so much. So it's not very likely. Just throwing that out there....

Wyo

Gary - What's your method for breech seal adjustment? When I changed the barrel on my Zoraki HP-01 (same as Alecto as you know) from a .22 flush nose to a .177 extended I tightened the barrel clamp just enough to hold it in position, but still allow it to slide under pressure. I then lightly pressed the muzzle down onto a towel over a board until I felt it was just sort of lightly compressing the breech seal, then fully tightened the barrel clamp. I tested the resulting FPS and I'm satisfied that it's as good as it will be, but I was wondering if you have a different technique.

[WyoMan]

I tightened the barrel clamp just enough to hold it in position, but still allow it to slide under pressure. I then lightly pressed the muzzle down onto a towel over a board until I felt it was just sort of lightly compressing the breech seal, then fully tightened the barrel clamp

Exactly, Dennis. Except for one thing maybe, I did that with two pumps in the gun. It worked. thanks-

Wyo

[Stinger177]

I tightened the barrel clamp just enough to hold it in position, but still allow it to slide under pressure. I then lightly pressed the muzzle down onto a towel over a board until I felt it was just sort of lightly compressing the breech seal, then fully tightened the barrel clamp

Exactly, Dennis. Except for one thing maybe, I did that with two pumps in the gun. It worked. thanks-

Wyo

Two pumps - interesting. Two pumps would be the mid range of pressure for the three allowable pumps on my HP-01 (well, not exactly, as compression is not linear) but anyway, it seems that would create a bit of pre-load between the seal and the barrel face. Once that air is released, would the seal not then be relaxed for the next "first" pump, and therefore not be as tight without that pre-load? 

I guess I'm a bit confused as to what the two pumps do.