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Discussion Starter · #1 ·
At my last range session when 20 out of 20 hot handloads failed to eject, I became aware the extractor only hangs on to a fired case by a small corner. Couple this with a chamber that is less than brilliantly smooth and the picture becomes clear. It takes more than a small extractor corner to pull an expanded case out of a less than polished chamber.
First the chamber, feed ramp , bolt face and the rib under the slide were burnished bright with Cratex rubber bonded abrasive wheels in a Dremel. This took less than five minutes.
The extractor was addressed next.
Several things have to happen to make the extractor better grip the case rim when the barrel is tilted down during the extraction cycle. The case is now sitting with the extractor at the 10 o'clock position with only the lower corner of the claw gripping the rim, so the claw needs to be reshaped to be tangent to the rim groove. First the claw needs to be brought in closer toward the center of the cartridge case by judicious grinding of the extractor flat where it stops against the slide. Then an angle cut across the claw needs to be made to be tangent to the cartridge rim groove. If you're real good with delicate stuff then you can radius the claw for a perfect fit. Use a number drill shank in the roll pin hole during the fitting.
This is followed by cutting 1 1/2 coils from the extractor spring.
When you're done, radius the extractor front so the extractor will bump over a chambered round. polish everthing you've roughened up.
This job can be done with Swiss files but the Cratex wheels give a better finish. I don't believe in sandpaper on machine parts.
This essential, extractor modification has been covered before and really should be incorporated into production.
A session at the range yesterday gave me complete confidence in the pistols' reliability in both slow and rapid fire using FMJ standard velocity handloads. Examination of fired cases showed full width extractor marks.
The ejector pin was shortened about 1/32" to help in both ejecting a loaded cartridge and helping a fired case to clear the barrel hood (and my forhead). This helped to some degree as fired cases were not deformed at the mouth. Losing energy by banging into the barrel hood makes cases fly lower.
After coming home, I thinned the rear of the barrel hood by grinding and polishing in the hopes that cases will miss it completely and fly higher.
Next range report will cover the results of the hood mod and
hot handloads.
 

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Careful you don't adjust the extractor so it's only reliable with one type of ammo... gotta leave some wiggle room for all kinds.
Oh yeah.. ALL my mods involving chamber/ramp work are done EXCLUSIVELY with files and sandpaper... I won't allow a Dremel anywhere near these areas!
Flyer
 

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Discussion Starter · #3 ·
Extractor mod further testing

A second trip to the range gave a 100% extract & ejection rate with both the hot 4gr Unique, 115 gr XTP handloads and the Standard velocity FMJ handloads. Cases seemed to disappear and were hard to find in the grass. I did get a hot, hard one in the mid forehead though. That was disappointing because of higher expectations from shortening the ejector and thinning the chamber hood.
Cases had only a minor "D" shaped mouth and were more suitable for reloading than before the mods.
 

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Discussion Starter · #4 ·
continuation of mods and range results

All brass flew clear of the pistol. Two to the side and the rest high overhead as observed by bystanders. All ammunition fed with no failures to extract/eject. Rapid fire was without event.
The slanted extractor described above, is a success.
The barrel really doesn't need a hood to function so wanting to direct ejected brass to the right, I removed the right half the hood.
Iwould have removed it all but it needs to act as a slide stop. If the slides' cartridge guide were moved forward or the rib on the barrel moved rearward to act as a slide stop then the barrel hood could be removed and ejection improved. As it was, I question this improvement and submitted it for evaluation as I have run out of ammunition.
If not a functional benefit, one can readily note if the chamber is loaded.
Brass is not mangled with or in spite of the mods.
While the extractor mod seems to work 100% but I believe more work can be done by lengthening height of the claw (and its' cutout in the slide) upward. This will keep case rims captured as they are bounced upward upon striking the ogive and case lip of the next cartridge in the magazine.
 

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Discussion Starter · #5 ·
Chronographing the \"hot\" 380 handloads

At least five years ago I assembled some 115gr XTP bullets on top of four grains of Unique and just today chronographed them. They had to be compressed loads due to the conical, long bulletand I was nervous about them. They turned out to be no big deal at 769 fps and 151 ft lbs. out of the Keltec. The kick was greater so I expected more oompfh.
At these velocities, lead or plated lead should be better than JHP.
 

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The barrel really doesn't need a hood to function so wanting to direct ejected brass to the right, I removed the right half the hood.
Iwould have removed it all but it needs to act as a slide stop.
Um...
Alarm bells are ringing very loudly in my head.
The lockup of the P-3AT is achieved by pressure of the slide against the barrel face, and the first (and main) place the slide contacts the barrel on it's return trip is the barrel hood.
Also, don't forget that's not the ONLY reason for the hood... it prevents round from simply hopping ABOVE the chamber and flying right out of the gun. It's a guide.
I'd keep an eye on the remaining portion of the barrel hood, and make sure it's not getting peened or rounded, since it now offers only half as much surface area for slide impact; therefore it's going to take twice the battering.
Flyer
 

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Discussion Starter · #7 ·
Barrel Hoods

Many auto pistols don't have hoods . It depends on alignment of cartridges in the magazine with respect to the chamber. In the case of the P3AT, cartridges sit so high in the magazine that it's almost a straight shot into the chamber.
They sit so high in fact that I believe they are primarily responsible for ejection; being high enough to interfere with extracting brass when the barrel is tilted down.
As you may have noted, I said the slide stop function can be performed between the ridges on the barrel being lengthened to impact the cartridge base guide of the slide.
These parts are alloy steel hardened to about Rc35 and can take a beating without peening provided there is reasonable crossectional area. Of course all cuts and angles were carefully polished to avoid fatigue failure with a ...DREMEL.
 

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MANY autopistols don't have hoods?
Well, offhand, only a couple come to mind... the 1911, of course, and the Browning Hi-Power.
You're mainly speaking of the Beretta 92 series, I suspect... what you're failing to take into account is the falling wedge locking system that Beretta adopted from the Walther P-38 in 1951.
With this system in place the chamber has very little actual drop... and that, coupled with a magazine designed so there IS a direct shot into the chamber, malfunctions are very rare, indeed.
However, let's simply ignore the Beretta and concentrate on every single other auto I'm aware of. Some don't have hoods; they ALSO have the bullet entering the chamber as the slide is COVERING it during the process.
You COULD elongate the slide's "wings"; you'd have to elongate the barrel tang (hood) also. Six of one, half a dozen of the other. I don't see much affect on function at all, except a possible loss in reliabilty due to the required increase in slide travel such a modification would require.
Frankly, too, the Rockwell figures don't really matter one way or another, for the purposes of this discussion. ANY hardness is going to be affected with a loss of a supporting cross-section. If it's malleable enough, it's going to peen tremendously. If it's just right, it's going to peen. If it's really really really HARD it's going to take that battering, and take it some more... and finally the thing's simply going to crystalize and fall into the bottom of the pistol in a shower of dust.
When I worked up my barrel hood mod, I was EXTREMELY careful to leave the entire upper mating surface of the hood ALONE for at least 3/16" of it's thickness.
Before I've EVER posted a mod, I've ensured to my personal satisfaction it would NEVER compromise the pistol's strength in any fundamental way. I have made MANY other modifications I haven't posted. Why? Because they'd be DANGEROUS.
Your idea of removing half the hood is an interesting one, and somewhat reminds me of the function of a Kahr pistol, with a feed ramp located left of center and the hood somewhat truncated on the right. The pistol was engineered to function in this fashion, however, and no lockup integrity was compromised.
In short, I'd have to say I discourage anyone from doing this to their pistol. No, I'm not God, or even the world's best pistolsmith... but I DO know what I'm talking about, did it for a living for quite a few years, and feel that's pretty much enough to validate my concerns.
Flyer
 

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Discussion Starter · #9 ·
Polish +extractor mod

Flyer, I've done a bit of thinking about the P3AT and have come to the conclusion that you are not doing readers a service by responding with limited understanding of P3ATs and their problems as though you had valid answers.
In doing so , you are " playing God" (as you deny) when you could be silent and perhaps learn something .
After all, if you had the answers, this forum would only have lasted a week since the problems with the P3AT are few and the same repeat over and over again.
It is clear you aren't reading my posts thoroughly and don't understand the implications of what I'm talking about and/ or have the technical expertise to evaluate my experiments, their merits or implications. You present a lot of speculation as fact.
A lifetime as a gunsmith does not make you a gun designer or an engineer any more than being a mechanic does
As I said, my intent is not to provide education outside of solving the Keltec problems that have proven out for me such as the tapered extractor claw and getting the information to Keltec and the readers.
There are several additional, meaningful mods in the works for the P11/40/357 in the works. plus a few more for the P3AT.
Incidently, I made my first Zip Gun during WW2 and have had a heavy technical firearms background in between also involving experimental automatic weapons and semiautomatic small arms operating at up to 75,000psi. I've seen some of these Keltec problems before and solved them.
I appreciate objective comments but not subjective ones presented as fact.
 

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Okay, flybob.
Don't say I didn't say I made things clear.
I AM a gun designer. In fact I've got a prototype of my newest design right here. Looks nice, needs final fitting and finishing.
I beg to differ with something you've said... I DO know the P-3AT inside and out, and thoroughly understand every single aspect of it's functioning, right down to the proportions of it's slide stop/lug angle and degree of muzzle tilt during unlocking. I have a few special tools I've made myself for working on these pistols, including a special "press" used only for removing the plastic frame pins - no more pins and punches over a hole in a board.
I'm shooting .32 NAA in a P-3AT now, as I put everyone on notice about MONTHS ago, through a barrel of my OWN design and construction.
I don't know what's come over you... maybe you've been bitten by a rabid bat, with the unfortunate consequence of missing treatment.
Also, what's with the "Upcoming developments in KT" crap, too? My man, I'm USING one of the "Upcoming Products", right NOW! Works great, too!
I can only conclude you're bitter about something or another I'm not privy to.
I can also admit that my father was a part-time armorer in Korea, too, and now he HATES guns. Your former experience in this area means nothing to me. I prefer living in the here and now.
In any event, you're obviously not one of us, anymore.
Sorry. But, Goodbye.
Flyer
 

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What in the world is going on? Differing opinions are fine even healthy, but the rudeness and arrogance, duh, especially to a forum partner is death.

Which brings me to my next Limerick:

There once was a dude named Bob...
Who thought being a jerk was his job...
Down was his fly...
So we waved goodbye...
I don't think I'm going to S0B...
 

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Yeah, I dunno what happened...
I really did NOT want to do that, but there's no WAY I can let someone claim cutting away half the barrel hood is A-OK, and who begins the process of questioning my ancestry because of my concerns.
We DON'T do things that way here... and we never will.
Flyer
 
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flybob a gunman supreme
made mods that he thought supreme
at least that's what it said in his dream

he questioned the advice of our Flyer
who invented the wonderful Flyerwire
and who's advice we all admire

flybob is no more, got hit in the a$$ with the door
on his way out of here landed right on his ear

and I think we owe Flyer a beer :cheers:
 
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