[1917-1911M]

I can usually figure out something, somehow, but this one has me stumped. If I take a variety of .380 mags....load 2, 3 5 or fully fill it, the body of the rounds sit against and parallel with the mag lips.

Not so with any of the .32 mags I have. Stock Walther measuring 0.227" front lip width and 0.294" rear of the lips. The second round no longer fits against the lips...the nose can be lifted up and down. On a newish MecGar measuring 0.282" front lips width and 0.286" rear lip width, same story. The second round and all following that progressively dip the nose down a little more with each round added. On my recent experiments with Walther PP and Bernadelli .22 mags I saw the same process. Well, naturally. .22 rounds have a rim that sticks out past the body and they stack in a curve. Adding stagger slots to the above mags totally eliminated this problem of the nose dropping. Which is why P22 and Smith .22 and a lot of other mags come with rim stagger slots. The slot allows the cartridges to slide off of each other sidewise which allows the nose of the upper rounds to sit in the mag as designed.

But what about a .32. That cartridge has a rim also but the rim only sticks out about 0.01" and when stacked at a slight angle the rim of the top rounds sits in a recess on the rim below...effectively letting the rounds sit side to side. No need for stagger slots. So the question is, why can't I get my rounds to load into the magazine and keep the nose of each round at the proper height to be parallel with the lips?

The old Walther .32 mag I have has the top of the follower sitting at 104.3* measured in the mag and up the spline and across the top of the follower. The first round fits fine, the second round and the rest all sit nose down. On the MecGar the follower, removed from the mag and measured has a rear angle of 105.2*. And, the second round begins to go nose down. This should be easy to cure I thought...I have a spare follower and if it will withstand the bending, I'l just change the angle of the top of the follower until the stack sits like I want em to.

I began to carefully bend the rear leg outward to pitch the top of the follower up at a steeper angle. I kept the mag body handy because I needed to bend the front leg in until the part slid up and down the mag freely. New angle 108.3*. Good for one more round before the third round would go nose down. OK, let's bend it a bit more - 110.5* and sure enough all was good until the 5th round. I seem to be on the right track, so, I'll bend it some more. 113.5* and now I'm good until the 6th round. Hmmm...this is getting to be a pretty steep angle. I wonder how the top two rounds are going to feed with not much support on the rear of the cartridge. They manually fed fine. Then, 115.8* and the 6th round was still nose down. OK, time for more slant but instead of risking breaking the follower I decided to build up the nose with small strips of tape. Nose only. 118* and the 6th round still went nose down.

At this point I gave up thinking this is going to take more thinking. The problem is...I'm out of ideas. The cartridges are stacking properly. The rims are not sitting rim on rim nor is the slant so much that the rims no longer sit in the recessed portion of the round underneath. For some reason I cannot get the mag to support the front of the case as the stack adds up. Anyone have any ideas?

Perhaps it is a moot point since the pistol cycles perfectly with all ammo tried to date even with the nose down. I sure thought this would be a simple fix and make the rounds sit like .380 rounds. 1917

This is what I'm looking for...all rounds stacking in the mag with the top round sitting like this.

But this is what I'm seeing. The first round only sits with the body against the lips unless the follower is modified. But kicking the nose of the follower up 13* never got me past five rounds sitting properly. In fact it was no better than an increase of 5*.

Picture of how much slant I added to the follower. Stock one on top.

 

[1917-1911M]

I should note that up in the FAQ Stickies (where no one ventures) MG Mike posted some factory .380 mag lip inner width specs. I think they were 0.291" rear and 0.283" front with a +0.008" tolerance. If I recall correctly, he later posted that he had come across some .32 caliber mag specs and they were the same as the .380. So the Walther mag I have is almost to spec and the MecGar isn't. Yet they both function fine. 1917

 

[halfmoonclip]

1917', does the gun run? My .32s are a stuff 'em in, shoot 'em out proposition. All of them, including the 20 round CZ neutered buzz gun.

I know you meditate on mags,and some of your reflections are amazing.



The Smith .22-15s mags are wonderful, and feed 25 rounds without drama. The semi-staggered P365 mags are another outside-the-box thing that let 10 rounds be stuffed into a really small pistol.


But what is up with your .32s?
Best,
Moon

 

[1917-1911M]

The pistol runs fine 100% even. But the rounds don't stack in the mags like they do in a .380. I've seen comments on this a number of times here...i.e., "your rounds aren't sitting right in the mag." Not necessarily mine. I think I read somewhere recently that the rounds should sit parallel with the slope of the feed lips. Mine don't...a number of people have said their's don't. So, I've been wanting to see if I could make em fit in there up against the lips. Nope, haven't figured it out. I really think it has something to do with the rims and how they fit against the underneath rounds. There might be a make or two of ammo, perhaps European, that stacks straighter.

Yeah, those .22 mags all worked.....ugly....but they worked. The Smith ones were particularly important because you can purchase all of those you want for $20 or so. Keep your originals for show and shoot with the modified ones. I still need to order a Bersa .22 and see what mods one of those needs. 1917

 

[jehzsa]

I really think it has something to do with the rims and how they fit against the underneath rounds.

I think that's it. The rims make it stack higher at the back than at the bullet end.

Fwiw, same thing with my Beretta 70. It doesn't affect function.

 

[halfmoonclip]

Uhhh, 1917', if it runs 100%, you could futz with it 'till it doesn't....
Yeah, there is variation in the groove ahead of the rim on .32s, but, especially if you put the rim of the round above in the groove of the round below, all should well. The powerful springs on blowback guns should overcome any resistance.

Seriously, worry about climate change or something; leave the mags alone.
Moon

 

[1917-1911M]

I did leave the mag alone. I had an extra follower and that was the only part I worked on. Not sure there is anything else that could be of any benefit. I was worried the follower might snap with a little bending but it didn't. It actually holds five or six rounds up against the lip compared to an stock one only being good for one round. But six was the limit. I added tape to the front to kick it up even more without further bending of the follower but...six was all it was good for and the sixth one was iffy.

So, unless someone can figure out a different approach that was all that I could make fit against the mag lips and apparently it isn't important anyway since the stock mags work 100%. One day I will put the modified follower in just to see if the pistol will function when firing. I think it will. And, it doesn't appear these pistols are as touchy as we sometimes think they might be.

Climate change is real...but I won't be here for the worst of whatever happens. People will adapt and find a way...although they may sure look back on these as the good ole days. 1917

 

[UniversalExports]

The reason is because the .32 ACP is a semi-rimmed cartridge, whereas the .380 ACP is a rimless design. For that reason, the.32 ACP case is never going to stack completely against the magazine lips as does .380 ACP. That's true of .22 LR as well, by the way, and for the same reason; the top round's rim contacting the magazine lips prevents it.

If the gun runs 100%, you're good to go and the magazines are operating as designed.

 

[1917-1911M]

It isn't that the rounds won't sit case to case, they can as the small rim sits in the recessed area of the adjacent rounds. I'm wondering if the angle that they stack doesn't allow the rim to sit like shown above. The top round was to illustrate rim lock. Something I find impossible to create when loading a mag.

I think i will measure the angle of a stack as above, then measure the angle of the mag to see what the difference might be. 1917

 

[UniversalExports]

Yeah, I misspoke. I realized it a short time later as I thought about what I wrote, and came back to edit my post when I saw yours. I should have said that the semi-rim of the top cartridge contacting the magazine lips prevents solid contact between the main body of the case and the lips.

I see this with all my .32 ACP and .22 LR magazines.

 

[MGMike]

A few random thoughts:

1) UE is of course correct for purely geometric reasons. A rimmed or semi-rimmed case will never mate exactly against the magazine feed lips because the rim protrudes enough to create some clearance at the rear just forward of the rim. But the case needs to be in contact with the front of the lip as the cartridge moves forward in feeding.

2) The attitude of the top cartridge is the only one that matters, and perhaps the one under it. Worrying about the 3d, 5th and others below is waste of time and attention, so long as the column moves smoothly upward without stubbing or hanging up, or otherwise interfering with the pressure constantly exerted by the magazine spring.

3) The magazine does not function in isolation and cannot be understood that way. It is part of a feed system, two major components of which are the feed rib on the underside of the slide and the feed ramp.

The feed rib must extend low enough (or the magazine must be held high enough) that its leading edge will strike the back of the top cartridge in the magazine low enough (toward the primer) to overcome the tendency of the cartridge to pivot nose downward; it also has to hit fast enough (i.e., hard enough) to drive the cartridge horizontally forward against friction from the column below. And there has to be enough time for this to happen, which is why recoil spring and magazine spring balance is vital. If the magazine spring does not fully present the top cartridge high enough in the instant available (especially if there's not sufficient slide overtravel before the slide returns to battery), the rib hits the cartridge rim too high, and it nosedives.

As the cartridge moves forward, the bullet nose --if it's long enough and the right bulbous shape, will be bumped upward by the feed ramp so that --if everything is timed and dimensioned correctly--when the magazine lips release the cartridge rim, the nose of the bullet will be practically in the chamber mouth. The duration and distance of unguided free-flight is minimized.
This illustrates why magazine design is so precise, and so ammunition sensitive. It also illustrates why bottleneck cartridges like 7.63 Mauser and .357 SIG are inherently less susceptible to feed stoppages.

4) It should be recognized that with the slide closed the top cartridge in the magazine is not resting against the feed lips like it is before the magazine is inserted. It is pushed downward slightly by the feed rib, and will be more or less parallel to the slide, not the lips. The cartridge rises only when the slides opens. In many Walther magazines --notably the P38 and P5, that quick upward movement flips the nose of the bullet up; the cartridge below may stay nose down until it's its turn to be fed. This does not seem like an especially positive arrangement, but it undeniably works.

5) John Pedersen recognized this phenomenon and invented a feature to ensure this "flipping" action of the top cartridge with a semi-rimmed case like .32. It's part of the design of the original model Remington M51, and is just a small, strategically-located divot in the magazine feed lips of the .32 magazine. It's absent from the .380. He patented it, one of about 70 patents covering that gun.

Enough. I have other things to do today. But it's so refreshing to see insightful threads like M1917's (not the usual dreary "when was my gun made?"), that such issues deserve extended response.

M

 

[1917-1911M]

I could draw all of this in a way that illustrates exactly what is going on...but I would have to take careful measurements of ammo and the forward slant of the magazine. I don't really care what any of the rounds down in the stack are doing...it is the top one I'm concerned with. Even though all of my mags allow the top round to go nose down....beginning with the second round, the pistol feeds reliably. By changing the angle of the follower I was able to make the presentation of the top round fit tight against the bottom of the feed lips up to the fifth round. Add the sixth round and the forward portion of the case/nose would sit down and away from the lips.

This is what I was attempting to correct. With my original and aftermarket mags only the very first round will sit with the follower pressing the cartridge body against the underside of the lips. Add a second round and the forward portion of the case will not fit against the bottom of the lips. Modifying the follower corrected this up to the fifth round. i.e., the fifth round would sit fully pressed against the lips just like the first round. Additional slanting of the follower showed no further benefit.

What I suspect is happening is that the forward slant of the magazine does not allow the rounds to stack like they do in the picture I posted earlier. I think that while the rim sits in the recess on the case, the forward slant causes the top round to move forward just enough so that the rim slides up on the slanting portion of the case beneath it and perhaps all the way on top of the case. It should be very easy to illustrate this.

All I need to do is determine the forward slant of the magazine in relation to the angle of lips. Then stack a group of 8 rounds to match that angle and have a careful look at how the rims are fitting against the lower cartridge.

When I install one round in a .32 mag, yes, perhaps the rim doesn't allow the rear of the cartridge to move up as much as the front portion of the cartridge, but the amount is minimal. I'm not even sure that the feed lips aren't designed in a way to eliminate this small lip. It seems to me, looking at the first picture in this thread that the top round when properly pressed against the mag lips sits pretty snug, front and rear of the case.

I'll check the angle of the mag in relation to the feed lips and the angle of a free stack of rounds and then match a stack to the slant of the mag and get a good picture of what the rims are doing. I'm pretty sure the mags don't allow them to stack like illustrated in the short stack previously pictured.

Yeah Mike, just fooling around Too hot to do anything outside. The right side of my lip is hugely swollen from having a small basal cell cancer removed today and Saturday I head to Houston and MDA for two months of radiation. I'm driving so at least I will have several firearms with me. Think of the mischief I can get into with an hour treatment per day and nothing else to do for 23 hours.....which is why I'm taking camera, guitar and paints. I find myself as interested in how firearms work as much as I enjoy shooting them. It all got started with a P22 that wouldn't work. Every other gun I owned or had owned always cycled properly, shot straight and all I did was clean them and feed them ammo. Looking closely at these semi autos has caused me to take a close look at a lot of the technical aspects of the designs.. 1917

Edit; I'd like to get my hands on the original engineering drawings. When I was 15, working construction for a masonry crew...at lunch one hot day in MS, I had my Spam sandwich in one hand, my now hot iced tea in the other and was looking at the blueprints of the building we were doing the masonry for. The super came over and told me to get away from his drawings. I told him I would but asked if he would like for me to show him the walls he had built in the wrong places first? He really scowled then and asked what I was talking about. I quietly showed him three walls that were in the wrong location. After lunch we tore them down...he didn't tell me to step away after that.

 

[1917-1911M]

Laying 8 rounds of Sellier and Bellot next to each other, carefully stacked on the top of my slanting drafting table top the stack staggers forward 12 degrees from vertical. This is placing the bottom cartridge where the slight rim hangs off of the lower rest so as not to displace it from horizontal, then stacking each round on top with the base of the top rim placed against the bottom of the lower round. This is as vertical as the stack can be made without one or more rims stacking on top of a lower rim.

Measuring the slant of the rear of the mag shows it to be 13.5 degrees from vertical. This means that the stack of rounds must be shoved forward. I'm not sure what happens inside of the magazine with the follower in play but if I take the previous stack and carefully press it forward to the 13.5 degree line a gap opens between the first and second round. This is with the top of each rim resting against the 13.5 degree line. Other than that, the rounds pretty much stack with very little if any shifting of the base forward and all of the cases appear to be resting against each other. I'm thinking that due to the slight slant of my table top and gravity, the rounds choose to separate between the first round on the bottom and the second round. Why? I don't know.

The follower on this particular Walther mag sits at 14.5 degrees past vertical off the rear of the magazine. The lips are 16.5 degrees off vertical. A photo or a drawing would make all of this much clearer. Tomorrow, perhaps. Adding all of this together, assuming the bottom of the magazine to be horizontal, the rear spline leans forward from vertical 13.5 degrees. The follower as measured with spring tension under it sits 104.5 degrees as measured from the rear spline. This adds up to the follower sitting +1 degree from horizontal, nose up when pressed against the lips. And the top of the lips sitting +3 degrees.

So what does all this add up to...beats me. But, it doesn't appear that the magazine slant is so much greater than the slant of a free stack of rounds as to cause the nose of the second round to fit nose down and not against the feed lips. And it doesn't appear to cause the rims to slide forward much if any on the lower cartridge.

 

[1917-1911M]

It seems this could be figured out in three rounds. If I place one round in the magazine, the case is pressed firmly against the bottom of the feed lips and I cannot move the nose of the round up or down. Add a second round and the nose can be lifted up to engage the lips. Add a third round and the nose can be lifted up even more. Beginning with the second round the nose can be moved up and down as stated but the preferred position is nose down. Why? It is only the failure of the top round (beginning with the second round) to be pressed up fully against the feed lips that this thread is about. 1917

 

[jehzsa]

Perhaps the following data might shed some light on the issue, 1917-1911M. In 2014, I posted on another forum that Remington and Buffalo Bore cartridges fit tightly on Beretta 70 mags, both OEM and Triple K. But that Geco, Fiocchi and Hirtenberger fit loosely and had a certain amount of "play". My recollection is that in describing that they fit tightly, I was referring that they fit pressed up fully against the feed lips.
https://berettaforum.net/vb/showthread.php?t=109206&highlight=bore

That post also notes that there are width differences between cartridges. I hope you don't go out to buy some but if you do find Hirtenberger I'll appreciate a heads-up (I'm out).

Significantly, in my Beretta 81 (double stack) all top rounds fit pressed against the lips.

Again, in my single-stack mags the issue does not affect function.

HTH


EDIT: Best of luck with your treatment.

 

[1917-1911M]

Thanks for the reply jehzsa. First, I'll have to admit that I've never heard of Hirtenberger ammo. Sounds German. I also have not measured the diameter of the cases of various .32 ammo but I will do that. What I have seen is that there is a difference in the case brand to brand regarding the shape of the case right in front of the rear rim. Some have a very short neck, some a bit longer and the slant from this flat portion up to the full diameter of the case varies. Which I was thinking might effect how the cartridges sit on top of one another, slanted forward and with the larger diameter rim.

For what it is worth, I am not mixing ammo on some of these attempts. I have not gotten to does Remington stack at a certain angle, Winchester another, Fiocchi still another or are they all about the same. The difference in each brand, small as it might be could certainly be a part of the problem. Perhaps a certain brand will allow the second and third rounds to load while keeping the body of the round fully pressed against the feed lips.

The mags do feed and function 100%, but, I'm trying to figure out why they don't stack like the first one does. I need to reinstall the modified follower and go back and have a look to see if that one is indeed pressing the entire case against the feed lips especially the first round. The other thing is that most of the stock followers that I have seen in these mags can tilt a bit forward or rearward due to the lower legs not being precisely fitted against the mag body. Again, this does not seem to be a problem. What would be a problem is the follower not moving up freely...so you can't make the follower fit too tightly.

Thanks for the kind words and I will take a look to see if all brands act in the same manner or do some stack better or worse than others. 1917

 

[halfmoonclip]

Let me state the obvious for a minute:
-.380s are cylinder section, and will stack evenly
-.32s are cylinder section, with a semi rim; the should stack evenly, assuming the rim nests correctly
-9mms are slightly tapered, so they do all sorts of strange things, depending on the magazine, which may have a pronounced curve, or a trapezoidal shape to permit stagger
-double stack/single feed mags are a different deal, and only need present the top round correctly.
Now, after all that, I'll quote Mike, who said something to the effect that magazine making is as much art as science. If they work, I don't question it. Kinda like a thermos bottle; it keeps hot stuff hot, and cold stuff cold...how does it know?
Moon

 

[jehzsa]

Hirtenberger is Austrian, 1917-1911M.

And take a look at this, https://forum.cartridgecollectors.org/t/32-acp-vs-7-65-browning-case-spec-variation/14786

Also, https://forum.cartridgecollectors.org/t/32-acp-vs-7-65mm-browning/3133

 

[jehzsa]

Here's what can be deducted from the information available:

1) Technically, .32 acp is not a straight-walled case cartridge;
2) Different manufacturers can use different cases;
3) Some cases are thicker, some are not;
4) The groove can be deeper or shallower depending on the case used by the ammo manufacturer;
5) The interaction between the rim, the groove, and the case can explain why some cartridges are not fully-pressed against the lips when stacked-up.

 

[1917-1911M]

So, the area in question is called the extractor groove. I've seen some specs on it here or there somewhere. Usually overall length and angle of brass as it transitions back to the od of the cartridge. This makes me wonder just how small the diameter of the rim could be made and have the cartridge still feed properly. The breech rail generally engages a sizable portion from my observations assuming there is no excessive wear to the magazine. 1917