Uh oh, more Para 12-45 Jams

[Drakejake]

I previously reported that my jamming problem with my Para single action 12-45 had declined and disappeared. Today I had no jams for three mags, but one jam in each of the last two mags--a failure to eject and a failure to load. I am using ammo that is reliable but dirty (PMP). Perhaps the gun needs to be worn in a bit more to overcome the dirt accumulated by shooting multiple mags. The 14-45 was again accurate and trouble-free.

Drakejake

 

[1911Tuner]

Mo' Jammin'

had no jams for three mags, but one jam in each of the last two mags--a



failure to eject

How heavy is your recoil spring? Is the extractor hook too long from the
area that touches the rim to the tip? (Spec is .032 to .035 inch.)

Is the slide getting full travel? Are you running a shock buff in the gun.
Does the case hang up sideways in the port or does it stay flat against the
breechface?



and a failure to load.

Vague. Failure to feed comes in a few different flavors. Describe it
exactly. Top round from slidelock? Last round? At random throughout the
magazine? Does the round enter the chamber at all...or does it stop
before it gets there? Where? At the junction of the ramp and barrel throat
or does it nose-dive into the ramp and never touch the barrel throat?

Not all that familiar with the double-stacks, but the basics are pretty much the same...

Standin' by...

Tuner

 

[Drakejake]

I have installed a heavier recoil spring from Wolff because the earlier jams were mostly failures of the slide to return to battery. Not sure if I can give more detail on the jams from today. The first involved an empty case that wasn't ejected. The second involved a round that didn't get all the way into the chamber. I haven't noticed any pattern regarding first or last rounds from the mags, which I believe are working OK. When I had the first jams, I had them both with the 12 round mags and the 14 round mags from my other Para. The 14 rounders worked perfectly in my P14-45.

Drakejake

 

[1911Tuner]

re: Mo' jammin'

Howdy Drakejake,

Okay...there's a few possibilities. First off...A heavier than standard recoil spring is NOT the cure for a failure to return to battery. If the pistol is right,
it should go to battery with a 10-pound spring. Overspringing the slide
masks the real problem and can bring on other issues.

Let's try the process of elimination.

Remove the extractor and the recoil spring from the gun. Load 5 rounds in
a magazine and see if the pistol will go to battery with a brisk push from
the rear using two fingers on the back of the slide. If it works, the extractor is your likely culprit. Either too much tension...or the hook is
hitting the case inside the extractor groove...or the front of the hook is
bearing on the angle just forward of the groove. If your gun has a stub
guide rod, leave the spring in, but at free length to keep the guide rod
from binding in the tunnel.

If it WON'T go to battery without the extractor, you may have a 3-point jam,
aka excessive stem bind. Have you noticed a crescent-shaped mark on the jammed cases just below the mouth? (Let me know on this one. The cure may get a bit long)

With the extractor out, use a dial caliper to measure the breechface. Flip
the slide upside down and look closely. You'll see two parallel "rails"
that are just below the rounded area. The distance between these rails should be .484 to .488 inch...but a bare minimum of .480 will get you by with ammo that is within-spec on the rim diameter...barely. .490 is better
for best feed reliability with any old ammo that you want to cram in the gun.
Some pistolsmiths will take that to as much as .495...

Lay the barrel in the frame with the slidestop pin through the link. Push
the barrel down and back and hold it firmly. The bottom of the barrel throat
should be a 32nd of an inch forward of the top of the feed ramp. It can be
a bit more, but not less. If the bottom of the throat is flush with the feed ramp, that's probably your bug. Quick fix with a smooth mill file, a scrape,
(The tip of a good pen knife will do) and a piece of 600-grit wet or dry sandpaper. Undercut the bottom of the throat a little and blend it in with the scrape. Just a little! Don't cut the throat deeper into the chamber...
just blend and polish it with the paper on your finger.

I've got a couple more suggestions and things to check...but this is gettin' long.

Standin' by for the results...

Tuner

 

[wally]

Not all that familiar with the double-stacks, but the basics are pretty much the same...

I'm very familar with double stack .45s. I'd say replacing the recoil spring with a stronger one was probably the wrong thing to do!

If its not an extractor problem as Tuner suggets, most likely need stronger mag springs to get the rounds up and into proper positon quickly enough. Problem gets worse as you go from P14 to P10 as the slide velocity increases (where a stronger recoil spring moves things in the wrong direction!). P14 tends to be most reliable by far, P12 might be the worse since P10 seems to have the same mag spring but two fewer rounds to push up when compressed to the same final working length.

Also need to keep the mags very clean inside as it doesn't take much to make the rounds bind where they make the transition from double to single stack near the top which causes the rounds to be late getting into positon generally leading to a "nose up" jam. Problem pretty much never happens on first or last two rounds as the force on these is usually OK from the nearly fully compressed spring or the light load on a nearly empty mag spring.

You might have to put an "extra power" Wolf P14 spring into a P12 mag to get it reliable whcih makes it a bear to load the last round.

If its the 3-point jam problem Tuner mentions, send it back to PO for repair under warrenty I hear their customer service is pretty good.

--wally.


PS:

If they are not genuine "MADE IN CANADA" PO mags. Pretty much 100% that the problem is the mags.