CJB
05-14-2011, 09:44 AM
Here's another weird problem.
I took apart the PM45 for its weekly wipe out - since it gets carried in my pocket daily, all day, except when I sleep (and even then, its under my pillow).
Put it back together, insert the magazine, press the slide release and... fails to chamber the round fully. It picked up the round, put it into the chamber, but the slide stayed back about 1/16 of an inch from being fully forward. Luckily I noticed. I pushed the slide forward. I sprang back on its own - 1/16 inch. WTF?
So... removed the magazine, unchambered the round, inspected it, and tried again with a different cartridge. Same thing.
Ok... do the above one more time. Same thing.
At this point, I took the pistol apart, dropped all three "defective" rounds into the chamber. They slid in easily.
Put the pistol back together, lock the slide open, and press the release with no magazine in it - same thing, slide failing to close that last 1/16 of an inch. Push it forward, it goes into battery, and springs out on its own when you quit pushing.
I tried a good dozen times and it failed about 5 out of that.
Here's what I found was the cause - after much looking.
The button on the front of the recoil spring guide was "just catching" the front of the slide. That part has a bevel on it - for a reason I suspect. The button was hitting "up" toward the barrel side of the opening. I took the gun apart, took the guide out, took the spring off, rolled it on my smooth bench, and it was straight not wobbly. Put it back together - yes both times the outer spring was on there correctly. It worked fine.
Not good enough. Back apart it came and I rotated the spring a little. Back together. Still fine. Repeat... repeat... ditto... until it failed again.
If you get the end of the coil at just the right rotational angle, it puts some weird pressure on the guide and the guide hangs up. I cant say if this would happen for all guns, but on my PM45 it likes that outer spring to have its coil's open end away from the barrel. That is, if the slide is on the bench, resting on its sights, the open end of the coil would be "up". Insert it down... and she'll catch. There's about a 15 degree spot there, where its likely to catch, all the rest is ok, but there's less pressure on the guide when the spring has its coil's end away from the barrel side of things.
Now thats weird. You can see the minor misalignment when slowly racking the slide, and it usually just hits the bevel, and goes home. But that one position... its off the bevel.
I'm wondering if this is a possible cause of some of the "pull trigger on chambered round, but no bang" issues that have not been attributed to trigger bar? I tried, and yes, with it stuck on the button, you can pull the trigger, but a pen in the barrel didn't jump like the striker hit it.
I took apart the PM45 for its weekly wipe out - since it gets carried in my pocket daily, all day, except when I sleep (and even then, its under my pillow).
Put it back together, insert the magazine, press the slide release and... fails to chamber the round fully. It picked up the round, put it into the chamber, but the slide stayed back about 1/16 of an inch from being fully forward. Luckily I noticed. I pushed the slide forward. I sprang back on its own - 1/16 inch. WTF?
So... removed the magazine, unchambered the round, inspected it, and tried again with a different cartridge. Same thing.
Ok... do the above one more time. Same thing.
At this point, I took the pistol apart, dropped all three "defective" rounds into the chamber. They slid in easily.
Put the pistol back together, lock the slide open, and press the release with no magazine in it - same thing, slide failing to close that last 1/16 of an inch. Push it forward, it goes into battery, and springs out on its own when you quit pushing.
I tried a good dozen times and it failed about 5 out of that.
Here's what I found was the cause - after much looking.
The button on the front of the recoil spring guide was "just catching" the front of the slide. That part has a bevel on it - for a reason I suspect. The button was hitting "up" toward the barrel side of the opening. I took the gun apart, took the guide out, took the spring off, rolled it on my smooth bench, and it was straight not wobbly. Put it back together - yes both times the outer spring was on there correctly. It worked fine.
Not good enough. Back apart it came and I rotated the spring a little. Back together. Still fine. Repeat... repeat... ditto... until it failed again.
If you get the end of the coil at just the right rotational angle, it puts some weird pressure on the guide and the guide hangs up. I cant say if this would happen for all guns, but on my PM45 it likes that outer spring to have its coil's open end away from the barrel. That is, if the slide is on the bench, resting on its sights, the open end of the coil would be "up". Insert it down... and she'll catch. There's about a 15 degree spot there, where its likely to catch, all the rest is ok, but there's less pressure on the guide when the spring has its coil's end away from the barrel side of things.
Now thats weird. You can see the minor misalignment when slowly racking the slide, and it usually just hits the bevel, and goes home. But that one position... its off the bevel.
I'm wondering if this is a possible cause of some of the "pull trigger on chambered round, but no bang" issues that have not been attributed to trigger bar? I tried, and yes, with it stuck on the button, you can pull the trigger, but a pen in the barrel didn't jump like the striker hit it.