The picture attached shows how I took care of the mag jingle on my M&P 40. It pushes the rounds close enough together to prevent the spring pressure from being on one side of the stack.
If you thought the 15th round went in hard before, wait till you check it out with 10 thousandths of room missing inside the magazine. It does load ok using a magazine loader.
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Append 1: ------------------------------------------------------------------
This is outstanding! After reading how John's extensions are working with the stock mag spring, I decided to shorten one to see how it works. I cut a magazine spring down by 1 turn. Reinstalled it with a new mag shim. Loaded 15 rounds without the mag loader. (It's tuff) No rattle. Fired several full mags starting with 1 chambered and 15 in the mag. No problems. Mag snaps in the pistol like it should. My main concern with the shortened spring was that the last couple rounds might not feed properly, and the slide would not lock back on last round fired. I fired 50 mags with 2 rounds loaded. Worked perfectly. Now I'm carrying 15 + 1 and two 15 round spare mags with no rattle.
I'm going to get spare springs and floorplates for my annual replacement now. Don't think I'll really need them before next year, but I want to be ready if the springs soften too much.
Apend 2: ----------------------------------------------
I now am selling "Mag Shims" for the 15 round M&P 40 magazines.
facts:
1. They are mostly hand made. If they start selling good I'll be stamping them with a die. = Nicer looking, maybe cheaper.
2. The last round is hard to get in. You will need a good mag loader.
(Shorten the spring like listed in Apend 1 and your good to go, if not, read on.)
Even if you only carry 14 in the mag, you won't rattle when you walk, and there is less pressure
on the magazine floorplate than a standard magazine with 15 rounds loaded. Carry spare mags with 15 each. These have slightly less pressure on the floorplate than a
standard 15 round mag, full, and inserted in the magazine well.
My older mag springs have softened a bit, loads easier, still functions fine, but I still use a mag loader.
(Before posting this I put a new shim in my newest mag. Without the mag loader,
round 14 was really hard to get in, #15 I could not get in until I used the mag loader.)
3. If your mags still rattle, return them and I'll refund your money.
4. I'm going to be selling a mag loader as soon as the patent is done. (It is really sweet.)
5. Weighed one for the IDPA shooters. 59 grain. equals .135 ounce.
Send a check with your order to the following.
Louisa Enterprises
P.O. Box 150
Letts, Iowa 52754
Minimum order 2. Price $7.50 each. This includes shipping and tax.
If you thought the 15th round went in hard before, wait till you check it out with 10 thousandths of room missing inside the magazine. It does load ok using a magazine loader.
-------------------------------------------------------
Append 1: ------------------------------------------------------------------
This is outstanding! After reading how John's extensions are working with the stock mag spring, I decided to shorten one to see how it works. I cut a magazine spring down by 1 turn. Reinstalled it with a new mag shim. Loaded 15 rounds without the mag loader. (It's tuff) No rattle. Fired several full mags starting with 1 chambered and 15 in the mag. No problems. Mag snaps in the pistol like it should. My main concern with the shortened spring was that the last couple rounds might not feed properly, and the slide would not lock back on last round fired. I fired 50 mags with 2 rounds loaded. Worked perfectly. Now I'm carrying 15 + 1 and two 15 round spare mags with no rattle.
I'm going to get spare springs and floorplates for my annual replacement now. Don't think I'll really need them before next year, but I want to be ready if the springs soften too much.
Apend 2: ----------------------------------------------
I now am selling "Mag Shims" for the 15 round M&P 40 magazines.
facts:
1. They are mostly hand made. If they start selling good I'll be stamping them with a die. = Nicer looking, maybe cheaper.
2. The last round is hard to get in. You will need a good mag loader.
(Shorten the spring like listed in Apend 1 and your good to go, if not, read on.)
Even if you only carry 14 in the mag, you won't rattle when you walk, and there is less pressure
on the magazine floorplate than a standard magazine with 15 rounds loaded. Carry spare mags with 15 each. These have slightly less pressure on the floorplate than a
standard 15 round mag, full, and inserted in the magazine well.
My older mag springs have softened a bit, loads easier, still functions fine, but I still use a mag loader.
(Before posting this I put a new shim in my newest mag. Without the mag loader,
round 14 was really hard to get in, #15 I could not get in until I used the mag loader.)
3. If your mags still rattle, return them and I'll refund your money.
4. I'm going to be selling a mag loader as soon as the patent is done. (It is really sweet.)
5. Weighed one for the IDPA shooters. 59 grain. equals .135 ounce.
Send a check with your order to the following.
Louisa Enterprises
P.O. Box 150
Letts, Iowa 52754
Minimum order 2. Price $7.50 each. This includes shipping and tax.
- Pic #1 shows shim inserted partially into magazine. Note the notch in the turned up end of the shim. It engages the catch on the floorplate, and is held in place by the magazine floorplate.
Pic 1
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