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Discussion Starter · #1 ·
Has anyone experienced the tumbling of bullets out of their P3AT? I don't believe that I've seen that problem commented on here, but on my first range session it appears to have cropped up...I think. If you have some experience with that, perhaps you can check out my posting here:http://www.ktog.org/vbulletin/showthread.php?s=&threadid=8484...and let me know what you think. Are there specific rifling problems to examine my barrel for or...?[/url]
 

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Yep, I saw the post at Ktog.
It's the first I've heard of tumbling problems. I seriously doubt your rounds were actually tumbling.. it's a possibility the target paper moved, or wasn't taped down evenly, that created the strangely-shaped holes.
Anything's possible though, I guess... any chance of putting up a pic of the inside of your bore? The only thing that could cause a bullet to tumble would be a VERY VERY bad rifling job. Even some of the bores that look like they've been threaded don't cause tumbling, though they probably decreased accuracy.
In short, your barrel would have to have almost NO rifling for this to happen. If you take a look at the rifling on a 1911 .45, you'll see rifling so shallow you wonder how it can possibly spin the bullet... but it does!
A pic of the bore would be a great help... employees of Kel-Tec are members here, and will likely chime in if they see anything amiss.
Flyer
 
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I am not sure that most people would shoot their P3AT at any distance that would give the round a chance to tumble. At up close distances i would imagine that even out of the worst rifled barrel that the round would still hit their intended target. But then again, I don't claim to know anything...... :?
 

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Discussion Starter · #4 ·
Re:

norfdet893 said:
I am not sure that most people would shoot their P3AT at any distance that would give the round a chance to tumble. At up close distances i would imagine that even out of the worst rifled barrel that the round would still hit their intended target.
Luckily, the distance was relatively close -- I wasn't going for accuracy this time around...just 10 yards, so that shouldn't have been an issue.

Flyer, thanks for the advice...actually, I did indeed try to get a shot of the inside of my barrel to post, but just wasn't able to make the lighting and camera work together this evening (after cleaning the pistol)...maybe I'll try again tomorrow in the outside daylight. Honestly, though, I'm certain that's not the problem, so I doubt if I'll waste anyone's generous time or this site's bandwidth to post it...I took a very close look at it this evening (more so than the quick glance I gave it on the inital field-strip cleaning before the first range session), needless to say, after I got it all cleaned up and gleaming inside...and the bore looks great. Very clean, perfectly pronounced rifling lines, with a very gentle and perfectly acceptable slight twist to the rifling. No other chatter/obstructions/burrs to interrupt the spin.

Which, in short, obviously makes me think even more that it must be an ammunition issue, which is obviously a great personal relief. I'll naturally keep an eye on it, and run several different brands through to confirm...but I think the likelihood that the fault lies with WWB is strong enough that the planned call to Kel-Tech can probably be delayed.

Flyer: "Yep, I saw the post at Ktog." -- By the way, hope I wasn't out-of-line by posting a reference here...I suspected there'd be some cross-duplication with the two sites' visitors, but hoped it'd be minimal enough not to cause a problem. My apologies to those who had to stumble across it twice...
 

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Re:"I am not sure that most people would shoot their P3AT at any distance that would give the round a chance to tumble."

I've owned several NAA mini revolvers in 22mag. All have produced tumbling as close as 10 ft. Not enough brl length?
 

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The only time that I've had problems with bullets tumbling have been when I've had damage to the bullet like a jacket separating from the core or a bullet defect. This happened when shooting handloaded 240 gr JSP bullets in a .44 Spec. at too slow of a velocity. It's my understanding that it can also happen when there is:

1. Mismatch between bullet weight and barrel twist
2. Mismatch between bullet caliber and barrel diameter
3. Insufficient velocity remaining to keep the bullet stabilized.

Correct me if I'm wrong, but I don't think that tumbling would be an issue with a rough barrel, unless one of the above would be in effect. It seems to me that the rough barrel should only affect cleaning and accuracy, depending on how bad it was.


FWIW,

emc
 

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Yep, a rough barrel would also affect velocity, too.
Strangely enough, it may make it go up! The increased friction a rough surface would present to a bullet's case would retard the bullet's movement enough to allow extra pressure to build up.
Flyer
 

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I have had a couple of suspect shots out of my p3at. However, I don't think it was the gun as much as the bullet. I had some irregluar shapes, but they were also well off the group and always very low. My suspicion is that the charge was very weak. These were also at 10 - 15 yards. ??? I don't really know what or why these happened, but just tellin ya what I have experianced. Yes, the targets were also well secured, top and bottom.
 

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Discussion Starter · #9 ·
Since the KTOG site was hacked and crashed, and my original post is no longer there for reference, I should say that the problem -- from all subsequent indications -- turned out to be nothing. Upon careful inspection after cleaning (I didn't pay that much attention at the original cleaning), my barrel looks perfect. I ran 75 more rounds through it the next range visit, at targets that were carefully secured and thick, with different ammo, and all new 75 rounds were just fine.

So either it was paper that was too thin (though I'd been using those same targets with my .22, 9mm, .45, .40, and .357Sig stuff for a while, and had no similar experiences), or the Winchester-USA (White Box) ammo. To keep matters simple, I will now simply avoid WWB in this caliber (as I do in most other calibers as well, come to think of it).
 

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Bullet Keyholing

I have experienced bullet keyholing with my P3AT. It occurs with the WW 85 gr STHP, and I think it is aggravated by the smiley issue. I'll try to post pictures here tonite, along with some additional observations.

Let me also say that I am new to this board and am very impressed with the breadth and depth of the inofrmation available here. The Kel-Tecs are great little guns, but I find it a shame that I have to come here to learn about factory upgraded parts, rather from the company itself.

I have been involved in firearms training for many years, and own both the P3AT and the P32. They are fantastic little guns that pay big dividends to the tinkerer. The information from this site has been most useful! I think out-of-the-box users might find the guns troublesome though.

I used to have a P-11, and didn't care for it, finding it unreliable. I also had the Grendel P10, and wished I still owned it: the blind magazine was quaint.

My P3AT and P32 have been very reliable as is, although a few modifications, as mentioned here, have made them 100% and more smoother.
 

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I noticed the problem at my first range session. WW 85 gr STHP would start tipping as close as 5 yards, about 20% would keyhole at 7 yards, and 80% at 15 yards. It was impossible to keep all shots on a "Q" target much past 15 yards, and almost none hit at 25 yards. hansen 95 gr FMJ printed straight-through shots out to 20 yards, although hits became spotty at 25 yards.

I was not aware of the "smiley" issue at that time. After I became aware and tested the effect, I found that my FMJ rounds had a very pronounced crevice in the nose, and the STHP would get "pinched" as if my a pliers. I did a Dremel "smiley modification", along with a small matching frame mod, and the problem completely disappeared. Accuracy improved as well.

Here is a target from today:
 

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Sorry for the large file size. At any rate, you can clearly see that out of 6 rounds of STHP at 15 yards, 2 keyholed, 2 tipped and 2 went straight through. Compare to the FC 95 gr FMJ load (which had the heaviest recoil of all tested), which went all straight through.

Post-"smiley mod", all ammo shoots a smaller group, with the FC 95 FMJ staying on the "Q" out to 25 yards

Even at 7 yards, 4 out of 8 STHP tipped:
 

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Discussion Starter · #14 ·
Thanks for the report. A few of your bad hits are similar to what I saw in my first experience. As mentioned, a change of ammo and target weight on my second range visit seemingly made the problem disappear, but I'm still concerned enough -- especially after seeing the similarity in your report -- to keep a close eye on it for further incidents. Found my target shots...here they are again, for your perusal/comparison.


 

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It occurs to me that the recoil of the P-3AT might be affecting bullet flight a little here... that muzzle is coming up FAST even as the bullet leaves the muzzle.
If it can cause the pistol to rotate so fast to result in brass to the face, it's possible it could cause a "wobble" to an occasional bullet, as well. Not true tumbling, but unstable flight nonetheless...
I think next time I hit the range I'll empty a mag into a target while deliberately limpwristing... see what happens.
Flyer
 

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I really doubt that limp wristing is an issue here... the bullet clears the muzzle at a definite point in time, and it doesn't back-up to strike the muzzle again.

The barrel isn't match grade by any means, and as posted above, the combination of rifling twist/barrel length/bullet bearing length/velocity/actual bore diameter and etc all play a part. In my gun, the STHP is marginally stabilized. Not really a big deal, I switched to the FC 95gr FMJ round and am pleased.

at-home, some of your shots appear to be tipping, what distance were you shooting?
 

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I really doubt that limp wristing is an issue here... the bullet clears the muzzle at a definite point in time, and it doesn't back-up to strike the muzzle again.
Nope, that's not what I meant.
The inertia imparted to the bullet as the muzzle is rising would tend to cause a "wobble" in flight. Think of a top, spinning on the floor - now give it a bump to the side. Immediately it goes into an asymetrical wobble.
You better believe the bullet can leave the muzzle after it begins rising! It can, and does.
Take a look at a .38 Special snubby, then a .357 snubby of the same size. Note that the front sight is MUCH higher than on the .38.
Why? Because the sights force you to hold the muzzle LOW, to allow for muzzle rise!
Flyer
 

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Re:

Flyer said:
Nope, that's not what I meant.
The inertia imparted to the bullet as the muzzle is rising would tend to cause a "wobble" in flight. Think of a top, spinning on the floor - now give it a bump to the side. Immediately it goes into an asymetrical wobble...
Yes, the muzzle rise does affect the angle of departure from the horizontal.... but this is true for any weapon, and not every weapon tips bullets like has been shown here. And it is true that every bullet has a certain amount of yaw after it leaves the muzzle, due the spin imparted by the rifling.

But the potential side velocity applied to the bullet during muzzle rise is very small compared to the velocity of the bullet itself... so that its effect is negligible in regards to excessive bullet yaw.

For example, the P3AT with a 85 gr STHP at MV 950 fps has a recoil velocity of appx 26 fps. A S&W Model 29 firing a 180 grain JHP at 1600 fps has a recoil velocity of appx 200 fps. [NRA FIrearms Fact Book, 3d Ed, 1989]

Yet the Model 29 is not known for excessive bullet yaw with that load, altho the P3AT has shown it, at least in my gun.

I think the factors in the case of the P3AT are a bullet of low sectional density, fired in a far-from-perfect bore of short length which does not adequately stabilize the projectile.

Not much of an issue really, as at the distance this gun is useful at (under 15 yards), it is still accurate enough, and the keyholing projectile still does damage. And there is always enough other loads to choose from which do not show excessive yaw.
 

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What you're not taking into account here is the P-3AT's weight.
Under 10 ounces FULLY LOADED, 8 empty.
There is absolutely NOTHING else on the market to compare it to.
I would suspect a large-bore derringer like a Bond Arms would cause similiar tumbling effects... this has already been reported in other forums where the cartridge is a heavy one.
There isn't a SINGLE OTHER PISTOL that's recoil velocity is so high the ejection port is directed squarely at the shooter's face, resulting in head strikes when held improperly. That's what my barrel hood modification was designed to minimize.
The timing of the P-3AT's locking system is tuned so that the muzzle is quite high before the hood disengages the slide. This is even more pronounced when using my home made .32 NAA conversion, in which I've had to adjust the timing to allow the slide to remain locked a trifle longer, in addition to a stronger recoil spring.
The act of limpwristing can and does cause instabilty in bullet flight. I just got back from the range, and did the test I'd posted about earlier. Several classic "keyholes" are clearly visible, whereas they're normal when the pistol is held properly.
Flyer
 

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Discussion Starter · #20 ·
Re:

Boomvang said:
at-home, some of your shots appear to be tipping, what distance were you shooting?
First time out at the range w/ it, so I wasn't concerned with accuracy or showing off my marginal bullseye technique, so it was at 7 yards w/ Winchester-USA White Box FMJ.

While I was concentrating on keeping my wrist locked, it's certainly possible -- since it was a new gun (and quite different from my other full-size pistols) and my first range visit with it -- that I had some limpwristed shots. That could account for the its sporadic appearance, perhaps...
 
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