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Discussion Starter · #1 ·
Hello folks,
Recently acquired a Beretta 950 B with a long barrel, like the picture at the end of this post. In any case, when I fire a round the used casing is ejected and a new round is loaded in the chamber, but the hammer is not cocked. In fact, sometimes it will fire two (or occasionally even three!) rounds with a single pull of the trigger. Though this might be desirable in some cases, I don't think this is how this pistol is supposed to work.

I guess I'd have a tiny monster on my hands if my gun fired all seven shots (six in the magazine and one in the chamber) with one pull of the trigger. I'm new to guns in general and I'm amazed at the weird whiny sound it makes when two rounds go off at (almost) the same time. I happens incredibly fast. Muuuch faster than any automatic weapon I've ever heard firing. But I would rather have the control of one trigger pull, one shot, and to know how many rounds I still have in the magazine.

I'm no expert, but I'm guessing the the the force of firing a round is not enough to overcome the hammer spring far enough to latch the hammer in the cocked position but is enough to eject the casing and load the new round. And I'm also guessing that it blows the hammer back enough that when it returns to the uncocked position it hits the firing pin hard enough that it fires the next round.

Can anybody confirm my thinking or otherwise guide me as to what might be going on and how to correct it?

If this thread is in the WRONG Forum, PLEASE point me to the RIGHT one.

Many thanks!

255878
 

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Discussion Starter · #3 ·
I'm retired, living the ex-pat life in central Mexico and the only ammo I can get is the Mexican Aguila brand.
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Thanks for replying. I'm grateful for your help but have to confess to knowing next to nothing about this gun, or any gun for that matter. Could you tell me a bit more what to look for?
 

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Since your post is more toward needing technical assistance, I am moving this to the "Technical Questions" forum.

As Bill mentioned, it also sounds to me like you have a problem with the sear causing it to go full automatic. Since I am not a gunsmith, I cannot offer any suggestions other than you need to find a gunsmith.
 

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Jake I do not know the laws in Mexico but I suspect they don’t like full auto guns. As Mr DeShivs says the sear is worn out, other parts have likely seen better days at this point. Get to a competent smith and get those worn parts replaced. Do not shoot it until then.
 

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Discussion Starter · #6 ·
You're right ral357, the authorities don't like full auto guns or lots of other things but the people don't seem to pay much attention. It's kinda like the Wild West around here, specially as you move away from the major cities.

I will find somebody competent to work on this problem. I have a feeling I might have to bring it states side though I have no idea what taking across the border might entail.

I'll be back posting when there's more to tell.

Thanks Bill DeShivs, gdmoody, ral357 and everybody on TFF
 

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Discussion Starter · #8 ·
I think I would be more afraid to bring it into the US and back into Mexico, than I would be just shooting it fully automatic!!
Thanks! but I don't think I'd call it fully automatic. It's more like fully unpredictable - and I would not say that's good. But you're right about the border crossings, specially bringing it back to Mexico after the Mexican border guards see it. And I wouldn't want to try to hide it from them. If I did that and they found it would be the scariest of all.

I'll be back to tell the rest of the saga.
 

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If you bought this gun in Mexico, I would be more concerned it was dumped after a murder and that the "automatic fire" was a deliberate alteration. Not sure I would want to keep the gun which could implicate you possibly with criminal activity. I wouldn't buy any gun in Mexico that was not brand new with documentation from a reputable gun dealer.

Just sayin. Hopefully I am wrong, but I wouldn't be surprised that the "defect" was deliberate. Once again, just speculating about this in a place you admittedly call "wild."
 

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I doubt the gun was "dumped" after a murder! That takes a lot of imagination.

The only other suggestion is to remove the grips, and soak the gun in mineral spirits, WD 40, or similar. Then, blow it out with an air compressor. It's possible that dirt is caked on the sear mechanism. I have never seen the 950 series with a bad sear, but it's possible.
 

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Discussion Starter · #11 ·
The gun was given to me by a friend I've known for 17 or 18 years. Where she got it I don't know but I'll ask her, in the hopes of dispelling the "dumped" speculation.

But back to the point of this thread. Since I last posted I've googled "sear" and "sear notch" for my own education. I also figured out it was easy to remove (and later replace) the hammer spring, and found there's a lot of greasy crud up where the spring pushes on the hammer (pardon my ignorant language...) so Bill's suggestion was actually already on my mind. Not so much to clean out sear and notch, which look clean enough, but because, though I've cleaned this gun before, as best I knew how, I thought old oil and gunk could be slowing down the movement of the hammer and sear, causing the problem.

Also, there is a shiny line where there is no blue on the edge of the sear notch. I suppose that could be wear. I would guess it's about 1/32" wide or less. But to my eye it does't look worn, it looks machined. All the same, it seems to catch easily and well enough, at least when I put it through it's motions -slowly- with my thumb.

Another point, though, is that as long as my finger is squeezing the trigger, the hammer will not lock into the cocked position. So then, after firing, of course the spring will slam the hammer back into the firing pin and set off another round! Is this the way it's supposed to work?! I would have thought, if it's a good design, the mechanism would be made so that the hammer would cock by the force of the previous shot, regardless of the position of the trigger! And there's no way I could release the pressure on the trigger fast enough. Me or anybody!

Any thoughts?
 

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If you remove your slide, the disconnector is at the top right of the left side of the gun (muzzle left.)
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You can also remove old dried oil/grease by soaking the frame with WD40 for a day, then blowing everything out with a can of brake parts cleaner (watch your eyes!) and then spraying a little WD 40 into the inaccessible spots for rust protection.
 

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Here is a schematic of the internals, along with parts information for the Beretta 950B Jetfire. There is no disconnector, per se, but I believe the trigger bar moves up to block the hammer from falling until the trigger is returned to ready and the sear is in place to catch it. I wish I hadn't sold mine so that I could take it apart and confirm that, but the design is familiar. Simple cleaning may well solve the problem, as Bill has said. If not, the parts list in the link provided should get you started.
 

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Discussion Starter · #14 ·
Okay! So I found the problem. After another THOROUGH cleaning I was still getting double discharges. So I took the slide and the grips off again, removed the hammer spring and tried to think through everything I seeing.

I realized that even with the slide on, if I turned the gun upside down things were not working right. It worked upright pretty well but changing the angle of the gun even slightly, the hammer would not cock. I realized it did NOT make sense to expect the sear to lock the hammer in the cocked position BY GRAVITY. So I looked at the schematic rawright54 pointed me to and found, sure enough, part number 29, 'sear spring' was there in the schematic but NOT in my gun.
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So, using the image on the NUMRICH website I MADE ONE out of a paper clip!
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And I put it in the gun.
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It's kinda hard to see, it's the shiny wire NOT visible in the first picture that IS in this one.

Then I took the gun out to my makeshift 'range', a place where I know nobody can stray across my line of fire and the bullet will hit the berm behind. Fired off three shots and, sure enough, a cartridge in the chamber and THE HAMMER COCKED after each shot!

I suppose if I'd had a little more experience that would have been an obvious place to start. Goes to show the value of getting advice from those who have it! In any case, as soon as I can, on my next trip stateside, I WILL purchase a proper spring from NUMRICH.

So, all the thanks to everybody here on TFF, specially Bill DeShivs and rawright54. Don't know if I'd ever have figured it out without the help.
 

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Just read this thread. Really cool how you all came together to fix the problem. And then J J getting creative to fix his firearm. Like reading a really neat short story with a happy ending.
 

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Discussion Starter · #16 ·
Thought I'd post a couple of thoughts to wrap things up.

First, The friend that gave me the gun (almost) never used it. She complained that when she did try shooting it, sometimes the round would not detonate. In fact when she gave it to me there were three cartridges in the clip with hammer marks on them but with the bullet still in the case. She said she did have someone look at it because of the misfires. I'm guessing two things, (a) that's when the sear spring went missing and (b) the problem was bad ammo, maybe wet powder, and not a problem with the gun. In any case, she doesn't remember who gave it to her or how she got it, it was so long ago, but I'm pretty sure it's never been involved in any murder.

Second, in response to Bill DeShivs post where he says "the disconnector is at the top right of the left side of the gun" and rawright54's post where he says "There is no disconnector, per se" between them they helped me figure out that when the slide is blown back by the recoil, it pushes the tab Bill DeShivs was referring to down so that the sear is let free from the notch in the trigger bar, which allows it to catch the hammer and prevent it from falling, leaving the hammer cocked and the gun ready for the next trigger pull to fire the next shot.
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I don't know if that tab is properly called a "disconnector" or not, but clearly it does fulfill the function of 'disconnecting' the trigger from the sear!

Anyway, the last week has been the best crash course in understanding, this gun, at least, that I could have hoped for. Two weeks ago I was a complete newcomer to the world of firearms. And I'm sure a lot of the terminology I learned applies to guns in general. So Thanks! to TFF and everybody here.

~JJ
 

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