Chambering the first round, a slingshot modification

[MO_Soldier]

Now, the issues with the mags cracking and floor plates falling off need to stop. And most of all, a redesign of the followers to reduce that dip in the front that seems to contribute to nose dives (shoot, it goes way too far back!), and a once and for all fix for the follower rubbing on the mag catch, must be addressed! If the problems mentioned in the last 2 sentences were fixed, wouldn't that solve the majority of problem incidents that we see on this forum? Some improvements in quality control and 2 simple design changes to one part, the mag, would reap such huge benefits for overall customer satisfaction and for Kahr's reputation.

Truer words have never been spoken. Unfortunately, it may cause less traffic to the forum though...double-edged sword?

[JFootin]

Truer words have never been spoken. Unfortunately, it may cause less traffic to the forum though...double-edged sword?

That would be good for us gun enthusiasts just enjoying our guns, humor, philosophy and a little bit of politics.

[MO_Soldier]

That would be good for us gun enthusiasts just enjoying our guns, humor, philosophy and a little bit of politics.

Very true. I must say, it's quite depressing hearing all of these problems...and honestly makes me think less of my gun even though it has done me no wrong.

[jlottmc]

Am I the only one who can slingshot his or her Kahr with no issues or modifications?

Both of mine slingshot with no issues. My wife still has a couple when she tries it, but I don't think she has the rip the gun out of your hand part down for that. I seldom use a slide stop for anything but a slide hold open device on anything including my CZ52 (look that one up, it locks open on empty but has only a bar to control that, no lever to push up or down, but I push the bar when I want it open.)

[jimsea]

a quick video of my results using Greg's mod.............

http://kahrtalk.com/showthread.php?t=9729

[dimden]

I modded all my mags by sanding the follower using a large Philips screwdriver wrapped with sand paper. My 7 and 8 round mag nosedive every-time while racking the side anything but very hard. So I sanded down the top part of the mag and it really made no difference. It did help my 6 round mags and when using Hornady Critical defense (very pointy round) I can slingshot by racking the side slowly. Just another data point.

[kiki]

Well i tried the mag mod. One one of my magazines and it did improve feeding, but only with rounds 124 grn or higher....my pm9 doesnt like 115 grn hp, unless there 115 fmjs.....besides that it feeds all fmjs and hps 124 or above.......115grn rem +p...are too short and they hang up on racking, sometimes on slingshot also....

[John222]

First of all, sorry to resurrect a two month dormant thread, but having read it end to end twice I have some input that may clarify some things ... it does for me anyway.

I will also say for the record that I own a PM9 and a MK9. They are fantastic shooters and my favorite guns. The PM9 is always with me.

The PM9 has never fte or ftf once. Not even during break in. The Mk9 has the nose dive ftf issue 1 or 2 rounds out of a box of 50. Hence my interest in this thread.

To me, the fundamental heart of the problem (for those that have one ... some don't and that's great) is that a 9mm casing is tapered by roughly .009 from the base of the casing to the top of the casing just behind the bullet. The more that bullets are stacked, the more that differential is multiplied. That's why the issue presents more with 7 round mags than 6 rounds. Glock solves this (as some Youtube videos show) by double stacking the rounds, allowing them to nest together which decreases the effect of the taper. This won't work in the more concealable, thinner frame, Kahr.

I'm not sure how or why the mod discussed in this thread works, because it doesn't change the angle of the bed of the follower. When the follower is at the bottom of seven (or 6) rounds, I'm not sure how it is 'supporting' the front of the round as the multiplied gap caused by the tapered casing is unaffected. As the rounds become fewer in the magazine, the support IS increased. Don't get me wrong ... I'm not disputing that it works .... in fact I am going to make the mod myself in hopes that it helps the occasional feed issues with my MK. I just can't wrap my head around WHY it works. That bothers me (anal that way ... you should see me with golf clubs!).

The two options that would completely solve the problem, as I see it, is
#1 a mag design that is slightly curved. This is impractical as it would take a redesign and retooling of the frame to accept it (I think).
#2 and more reasonable, would be to have the bed of the follower on a pivot between sides of the same follower. This would allow compensation for the slightly changing angle as each round is stripped from the magazine, and every round would be supported all the way through the stack.

This would undoubtedly be a more expensive magazine by a few bucks .... but, as I think through, a permanent and stable solution. Now ... someone with better credentials than I can feel free to discount my logic with real mechanical engineering facts that shows me wrong. I'm willing to get an education.

Just for fun I tried stacking some ammo to simulate your point. Results, you dead on. The taper causes the rake angle to change as shells are added to the magazine. So much so that the follower cannot compensate.
The mod to sand the follower certainly helps tip the nose up a bit, but it's not the whole solution. To solve the problem the follower needs to be able to compensate by rocking the nose up when the mag is fully loaded. Maybe they need a whole new follower design with a flat top like the promag and modified front and back legs on the follower to allow it to rock more, to compensate for the angle.

I'm tempted to protype an old style metal mag follower similiar to the one on my WW2 Walther PP.

[Tilos]

John222:
Thanks for the pic.

With the bottom round in the your stack parallel to the base plate, the fanning of the ammo is very aparent.

I would suggest adding the follower to the bottom of that stack, outside of the mag, this would shift the entire ammo stack "nose up" into the true operating position and minimize the ammo "fanning".

While your pic shows fanning, it does not show the ammo in the position it would be inside the mag with the follower.

Tilos

[FLBri]

Tilos, that's true, but it won't change the fact that there is a difference between the way the first round sits, to the way the last round sits ... because the follower never changes angle. I suppose, at best, it may situate the stack to a 'happy median' (or in some cases unhappy).

[John222]

Some ammo casings have less taper than others. I originally had a problem with my 1940 Walther PP with ammo like Remmington and Winchester. Too much taper and they wouldn't stack correctly. In this case, the solution was to switch to Fiocchi. They lay perfect in the magazine. In the case of the Kahr, with only 6 rds you would think we could solve this problem.

[jocko]

could

Tilos, that's true, but it won't change the fact that there is a difference between the way the first round sits, to the way the last round sits ... because the follower never changes angle. I suppose, at best, it may situate the stack to a 'happy median' (or in some cases unhappy).

possaby it be also the magazine spring pressure on the first round compared to the last round and possably the first round is now not sitting on the follower but on the second round, giving different angles between first and last round.

I try not to study the magazines/bullet/follower relationship to much if my gun goes bang every time. I guess for me if it is not broke I don't fix it. YMMV

[Tilos]

FLBri:

Correct, the angle doesn't change, round to round when fired, but by extending the follower contact towards the front, by sanding, fanning DOWN of the stack is minimized.

The extension of the follower, front and back, down into the mag is what keeps the angle of the follower constant from the 1st round fired to the last.

John, in my view, "some ammo casings have less taper than others" is simply wrong as all same caliber ammo is made to chamber standards.

Experts have spent their entire careers designing mags and we tweek them, but often the results are less functional.

The redesign of a follower requires a new mold which is a big expense and any secondary machining of the existing design can only remove material, not add any.

Tilos

[jocko]

oh I would suspect alot of these ammo casing dies could be off a few thousands + or -(*even different factory brass) but that should not effect feeding. These are not pocket watches, built in tolerances are takenin to accord . We seel every once in awhile inside mikng of the chambers and they can be off a few thousandes between two exact barrels. Really IMO doesn'tmean keitgher one is bad or good. It if works OK, consider it good, if not consider it bad and proceed to get it fixed. and if it ain't broke don't fix it.

[skiflydive]

Just a little different thought...nobody ever talks about the "ceiling" of the spring cavity in the follower. To me...(a manufacturer of stuff) it would be fun to measure the heights of the internal dimensions of the cavity. If it has a lot of variability wouldn't that affect the pressure the spring applies front vs back of the follower. Variability in the angle of the last coil of the spring would do the same thing