Para firing pin safety system

[frankie_the_yankee]

In the Series 80 thread, Greg recounted an incident where his Para Warthog took a whack on the rear sight, after which he discovered that the firing pin safety was somehow stuck in a way that disabled the gun. He went on to point out that the hole that the safety plunger rides in extends all the way through the slide, covered up by the dovetail mounted rear sight.

After re-adjusting the rear sight, he got the gun running again, but remains understandably concerned about field reliability.

So today, I was at my home range adjusting the sight of my new 6.45 LDA. (Out of the box, the gun shot a couple of inches to the right of point of aim at 10 yds or so.) I loosened the setscrew and tapped it with a brass punch to drift it over some. It was a bit stiffer than I would have expected, and I ended up having to whack it pretty good to get it to move. Then I snugged it up and went to test fire it to see how the adjustment worked out.

So with the gun on sandbags and loaded with factory 230g ball ammo, I carefully squeezed the trigger and got a great big "click". I held position for 10 or 15 seconds or so to make sure I didn't have a slow primer. Then I cleared the gun.

The chambered round did not have a firing pin strike on it.

I reloaded the gun and the same thing occured twice more.

The third time, the gun fired normally. Following that, I put 60 rounds through it (10 factory and 50 of my 185g semiwadcutter reloads) with no failures or stoppages of any kind.

Greg's experience, my drifting the sight, and the lack of a firing pin strike all seem like too much of a coincidence to be a coincidence. I figure there must be some connection between moving the sight and the firing pin block getting stuck.

But I cannot for the life of me picture what it might be. When at rest, the plunger is at the bottom of its range of travel and is not in contact with the underside of the sight dovetail. Only when the trigger is pulled all the way back is the plunger pushed upwards (where it may contact the sight dovetail at the limit of its travel) to release the firing pin.

So it seems that as long as the trigger bar works properly there should be no problem.

Yet, there obviously is some kind of a problem.

Is there something about the way the firing pin safety works on these guns that I am overlooking?

The gun conceals great. It carries great. The LDA trigger is great. And it is, for me, the best instinctive "point shooter" that I have ever shot. Draw and fire drills using either a "flash" sight picture or none at all produce great success. And the new Para mags hold 7 rounds giving me a total of 8 rounds of 45ACP in a very small package. So I have some strong reasons to want to get this thing sorted out.

Anybody got any ideas?

[Kalrog]

I have a 7.45 LDA and haven't experienced anything similar to what you are talking about. I just took it apart tonight and I couldn't imagine what could be the connection between the sights and the firing pin. I had to adjust the extractor, so I really did take it down a bit farther than normal too.

I am interested in hearing any additional information though! Have you thought to call ParaOrd? They might have some info...

[frankie_the_yankee]

This just happened today, so I haven't had a chance to call Para about it yet.

I just field stripped the gun to clean it and found that the firing pin safety plunger is stuck at the top of its travel range. This leaves the firing pin free to move so the gun cam fire. But the firing pin safety is effectively deactivated with the gun in this condition.

More to come as I continue to play with it.

[flintknapper]

Frankie,

This is your best source for an answer: gwedge@paraord.com

George Wedge is a great guy...and he will give you his full attention.

It might take a day or two to get a response if you email him, so be patient. Or, call him.

Please let me know what you find out. Don't want this happening to my daughter's pistol. In fact, I may the pull the FPB out until I hear what you find out.

Thanks,

Flint.

[frankie_the_yankee]

Frankie,

This is your best source for an answer: gwedge@paraord.com

George Wedge is a great guy...and he will give you his full attention.

It might take a day or two to get a response if you email him, so be patient. Or, call him.

Please let me know what you find out. Don't want this happening to my daughter's pistol. In fact, I may the pull the FPB out until I hear what you find out.

Thanks,

Flint.

I will take your advice.

In the meantime, here's what I've able to come up with on my own.

I decided to remove the rear sight to see what I would find under it. The first thing I noticed is that the last coil of the plunger spring was formed into a short straight section that was captured (or wedged) between the rear sight and the slide.

Here's a photo of the spring after removing it from the gun.



I do not know if this is normal or not, but I can see no reason to design it that way. I would think the whole thing would work just as well with the spring confined by the rail running along the bottom of the sight (that passes directly over the plunger hole).

After removing the sight and the spring I removed the plunger. This took a little work as it was a bit "sticky". When I finally got it out, here's what I found.



Notice the damage to the top section where it is actually cracked, and the dent in the barrel of the plunger. Obviously, this piece had gotten whacked somewhere along the way.

Of course to remove the plunger it was necessary to first remove the firing pin and spring. Inspecting the firing pin, here's what I found.



Notice the dings on the firing pin where it contacts the safety plunger. Not only is this unusual in itself, but if you think of it, these parts should never come in contact with each other in normal operation. When you pull the trigger all the way back to fire the gun, the plunger moves out of the way of the firing pin so they never touch. Only if someone (or something) whacked the firing pin with the slide locked back (and the plunger in the "down" or safe position) could damage like this happen.

I will be sending Mr. Wedge an email detailing all of this, and will keep the board advised as to his response.

I believe these to all be factory defects, and will be looking for Para to send me free replacement parts.

[flintknapper]

Very interesting.

Will you make it a point to ask Mr. Wedge if the plunger is an MIM part.

Betcha it is.

Thanks for the reply and the pics.


Flint.

[frankie_the_yankee]

Very interesting.

Will you make it a point to ask Mr. Wedge if the plunger is an MIM part.

Betcha it is.

Thanks for the reply and the pics.


Flint.

I will, but I don't think that's why it failed. It got hit hard by the firing pin, and that's not supposed to happen.

And the business with the spring just seems strange. It must have happened when the gun was first put together.

[striker55]

There is a good 1911 forum http://forums.1911forum.com/index.php scroll down to manufacturers and ask your question there. Lots of good folks there as well.

[G.C.Montgomery]

AFAIK, the LDA uses a modified version of the Colt Series 80 system that Para used in their traditional Colt/Browning system pistols. Peening of the firing-pin block by the firing-pin itself is a common problem in many pistols and not unique to the LDA. As an example, I've seen peening of the firing-pin block in Glock pistols. Also, the fact that it may be a MIM part is not normally an issue. Out of spec parts or improper timing on the otherhand could be and issue. An out of spec plunger, firing-pin, lever or other camming surface might be a result of a manufacturing error, improper assembly or damage resulting from dirt/debris impeding the movement of any part in the system. Incorrect timing, potentially caused by out of spec parts, can cause the firing-pin to peen a firing-pin block that has not quite gotten out of the way before the hammer falls. That's all that comes to mind. The LDA system is one that I would have checked by Para since it's proprietary and not commonly used by any other manufacturer. Alternately, there may be a gunsmith who knows the system well enough to diagnose and correct any problems.

[frankie_the_yankee]

Yup. It could be a timing issue. Though I would have expected to have gotten some sporadic failures to fire somewhere in the first 500-600 rounds I have put through it. Also, the plunger seems to have been hit pretty hard. And the damage is at the top of the plunger, which means that it was in its at rest position when the firing pin hit it. If it was a timing issue, I would expect that the damage would be further down near the "neck" where it narrows. (Like it almost was out of the way of the firing pin but not quite.)

But it's possible for timing to be involved. Thanks for the suggestion.

If Para sends me the parts, I'll probably detail strip the gun after another 500 rounds or so and check the parts for signs of contact.

[frankie_the_yankee]

The root cause of my problem, and from the description given most likely greg's problem as well looks like a defective slide.

The dovetail cut for the rear sight intrudes into the firing pin safety plunger hole as can be seen in the photo below.



As far as I can tell, this is probably due to the dovetail cut being slightly too far to the rear on this slide.

The matching dovetail on the rear sight does not extend across the full width of the sight. It only engages the slide cut in a narrow region located on each end of the sight. See the photo of the underside of the sight below. The engagement points are the rails that extend vertically on each side of the setscrew hole.



With the rear sight centered, neither of these engagement points extend far enough inwards to interfere with the plunger (through the openning created by the incorrect dovetail cut). But if the sight is drifted to the left, as I did intentionally or as greg had happen accidently when his gun hit the ground, one of the sight dovetails can partly intrude into the plunger hole and interfere with the action of the plunger.

What I think happened in my case is that after drifting the sight, the plunger was at first trapped in the "down" position, where the gun would not fire. But since the intrusion of the sight dovetail was very slight, after a few tries the plunger managed to slip past the dovetail, where it then got stuck in the "up" position. At that point, the gun will fire, but the safety is inoperative.

That this, or something very similar, could happen to both me and greg tells me that Para has a tolerance issue with these dimensions or possibly had a bad run of slides at sometime in the past, and greg and I both got one of the bad ones.

I can't imagine that the sight mounting would be designed such that the dovetail intentionally cut into the plunger hole.

I know that some would suggest that I just remove the plunger, put the gun back together without it, and enjoy it. But I'm too fussy about my carry guns to do that. It either has to work as designed or it's off to the smithy to put things right.

The bad news in this case is that the gun is gonna have to go back. I do not have the equipment or the detailed knowledge required to properly fit a new slide to my frame, barrel, etc. So a pro is going to have to do that.

Back to Para under warranty.

Mr. Wedge will be fully informed about all this when he opens his email Inbox Monday morning.

Anyway, I would suggest that Flint should detail strip the slide on his daughter's gun. With the sight centered, the firing pin should never lock up even with the bad dovetail cut. But you never know. And greg might want to take another look at his gun as well.

[flintknapper]

Thanks Frankie,

Will take a look at mine.

[frankie_the_yankee]

I talked to Joel today. He is a senior gunsmith at Para's service center in TN.

He told me that the intrusion of the rear sight dovetail cut into the firing pin safety plunger hole is INTENTIONAL. The gun is designed that way. I asked him why and he gave me a frank answer but swore me to secrecy first. He also told me that the end of the plunger spring is not supposed to be partly trapped under the sight like it was on my gun.

So the rear sight is NOT drift adjustable, at least not very much. Drift it too far to the left (around 1 mm) and the sight dovetail rails will interfere with the operation of the plunger.

So my slide is not defective. He said that because these are safety related parts, Para's normal position was that I had to send the whole gun back for repair. But he agreed to make an exception and send me a new plunger spring, plunger, and firing pin and that I could install them myself if I felt comfortable doing it.

For now, that's what I'm going to do. But at some point, I might have a gunsmith weld up the dovetail cut and recut it around 1 mm further towards the front of the slide. Then the rear sight would be drift adjustable and this problem could never happen again.

[gregthehand]

Very informative. I'm very suprised that the cut is intentional. Shows how willing I am to tolerate a gun! Fails once... GONE! I'm glad you decided to take things apart and see what the problem was!

[frankie_the_yankee]

I like the way it carries and shoots too much to give up on it. If I have to fix what I regard as Para's design flaw, I'll do it. I'm an engineer by profession. So to me, this is just another engineering problem to solve. It's what I do all day anyway.