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Discussion Starter #1
Has anyone experienced problems inserting a fully filled magazine into their FNP 40 (14 rounds)? I actually have to forcefully slap and/or jam the mag into the pistol to get it to latch into place. If I take 1 or more rounds out of the magazine and try again, problem disappears. The magazine slides right into place and latches securely with regular/normal effort (as compared to my other pistols). Gun and magazine are both clean. Anyone else having this problem or hear of it?
 

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Haven't had that problem with my FNP-40. Are you noticing this when the slide is forward or locked back? If the slide is forward, then the top round in the mag is pushed down by the bottom of the slide when the mag is inserted. A fully loaded mag will take more force to insert in that case than a partially loaded one because the mag spring is more compressed with a fully loaded mag.
 

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Discussion Starter #3
Problem is only occuring with the slide closed. Good call on that I had over looked that idea. I'll have to double check and see if it is in fact happening with all 3 mags. I would imagine it is the top round contacting the slide. I wonder if that is a follower spring problem or something else.
 

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If its happeniing with all three mags, then its probably normal. If you notice that one mag is harder to insert than the others, you might want to disassemble that mag, clean it and check the condition of the spring and follower.

All semiauto mags are harder to insert with the slide closed because the bottom of the slide behind the breach has a ridge that holds the top round in the mag slightly below the feed lips. When the slide moves back in recoil and opens the breach, the top round in the mag is pushed up by the mag spring. When the slide moves forward to close the breach, the ridge hits the back of the top round and pushes the round foward out of the mag, up the feed ramp and into the chamber. The ridge actually slides between the feed lips to do this, so when the slide closes, the bottom of the ridge is between the feed lips. That means the the next round in the mag is held slightly below the feed lips until the slide cycles again.

I'm probably not doing a very good job of explaining the mechanics, but the bottom line is that semiauto mags will slide into place will little effort when the slide is open, but take more force to insert when the slide is closed because the top round will be pushed back into the mag a little by the ridge on the bottom of the closed slide.
 

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Discussion Starter #7
Thanks Fabius. Good info on the feeding mechanics, your explanation made plenty of sense to me. I got out my other mags earlier today and both of them snapped right in fully loaded. So it is narrowed down to that one magazine. I must not have ever used that one before or I am sure I would have taken notice to this at some point. I'll inspect that mag and post my findings if anyones interested. Thanks for the help.
 

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Discussion Starter #8
Oh and just for the record, that troublesome magazine was by far harder to insert than ANY other autoloading pistol magazine I've come across, any brand and any caliber. So that should have pointed me straight to the mag. and not the gun since I have been shooting the gun flawlessly for months now...
 

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take another look at your magazines on one of mine on the follower on the corner where the slide catch makes contact the magazine follower is worn the true problem is corrosion due to use but for an expensive mag id expect they use stronger materials in the future this can inhibit a speed reload greatly but other wise im sure theres a quick fix
 

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Well since this topic was dug up I figure I would reply here instead of starting a new thread.

I am also having issues with inserting a fully loaded magazine (10 rounds, as I live in California) into the mag well when the slide is in the forward position. 1-6 or 7 rounds in the magazine and it will work fine, however if there are 8 or 9 it is stiff to push in, but when there is a full magazine, I really have to slam it in, and it is extremely hard to do, sometimes I have to try a couple times.

I know the round is hitting the top of the slide, because when I remove the magazine, the round is scuffed and sometimes dented on the top.

I am not sure if anyone has this difficulty or not, but I have a feeling it may be due to how they modify the magazines for 10 round only capacity. On the side of the magazine they have indentions which are the same angle as the follower and are the whole length of the side of the magazine on both sides, which will prevent the follower from going down any farther than where 10 rounds should be.

This is not my magazine, but it is similar to this


I have a feeling that because these magazines are made specifically to prevent adding any more than 10 rounds, that the follower does not allow any room for the found at the top to tip downward upon hitting the slide.

My main concerns about this are I may not be able to insert a magazine when I need in a life or death situation, as well as potential damage to the weapon from repeated hits to the slide, as well as potentially damaging a cartridge which may catastrophically fail.

I am not sure if anyone else other than the OP has run into this problem or not, but any advice or recommendations would be appreciated.
 
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