P Mags. won't work proper in my KAC SR-15

[kenner]

I just found out that P Mags. will not function proper in my knights SR-15 rifle, The problem is when I insert a loaded P Mag. I cannot close the bolt with either the right or left bolt release levers, with any of my metal mags. no matter who makes them I have no problem at all using the bolt release levers.
Anybody have any idea of what is up with the p Mags?

Thanks
kenner

[bp7178]

How many different Pmags have you tried?

[hkhunter]

I've never had this happen. I've had the last round not chamber a 1/2 dozen times, but nothing like you are experiencing. I would try some more pmags. I also had a problem with some pmags not dropping free when I hit the mag release, but I solved that by buying other pmags and found what worked and what didn't. I would start by changing your pmags.

[kenner]

I have tried all 20 round P Mags. I have 8= 20 rd. P Mags. and all of them do the same thing, thay are brand new, never have been used.
kenner

[Ferris2son]

This is a similar problem that my SCAR has. Try removing the upper and insert a mag into the lower, checking closely if the mag interferes with the bolt catch/mag release. Try pmags and others that function to see if there is any difference in those parts interacting with the mags.

You'll notice that STANAG mags have a square cutout in the rear while pmags are more "V" shaped. The bolt catch can hang-up on that V. If you think that might be the problem, Dremmel or file a little material off that notch and repeat the test

[mpom]

Have you contacted KAC ?

[kenner]

No I have not talked to KAC, I think ferris2son hit the nail on the head, I'm going to try and open up the back of the P Mag. a little bit and see if that works.
kenner

[Titleist]

Simple question, are you loading too many rounds in the magazine?

[kenner]

No, it does not make a difference 5 rounds or 19 rounds in the mag.
kenner

[Pappabear]

I run pmags in mine, never had a problem. But it sounds as though your problem is solved. Good luck. Dremel

[jjw]

any time you have to modify a new piece of gear its a bad piece of gear. we were discussing his same thing to day at lunch (p-mags) i dont have good luck with them but every one else seems to. so what the heck. i just dont use them. we all agreed we had good c=products that work fine but we all shoot a lot and fix what ever bugs pop up.

say over, they should go back to the vendor. u should never have to work on new gear. especially when used in a knacs rifle.

umwv

[jbo723]

I've had my E3 since the late 2008 and I've used close to 70-80 different PMAGS and haven't experience a single issue. I do have issues with the older versions in my LMT though..had to sand down the tabs on the rear spine to get them to drop free.

[az doug]

...u should never have to work on new gear. ...
umwv

I agree if the gear was made for the particular firearm make/manufacturer, model, etc. by or on contract for the original manufacturer. When the gear is made for a generic firearm design such as the AR-15 design, 1911 design etc. it is impossible for any one manufacturer to make an after market product that will fit and function in all the "clones" due to manufacturing tolerance and tolerance stacking. Gunsmiths have made a good living off of this issue for years by fitting parts.

Today with so many well designed aftermarket products out there if one does not fit or work you can probably find another that does. Or you can experiment and modify the part that did not fit. It is up to you. I enjoy tinkering and learning so I would try to modify at least one, especially if that modification did not prevent it from working in any of my other firearms of similar design.

[tobys]

I've had two SR-15's and used tons of PMAGs with each, never a single issue.

[az doug]

Tolerance stacking. Every manufacturer has minimum and maximum allowable tolerances. Also they make minor dimensional to their product sometimes and that throws things off.

That is the only explanation I can think of to explain why they work in your guns and not his. If it is tolerance stacking it is merely a combination from both manufacturers. If it is a minor dimensional change it could be on the part of either manufacturer.

[jwperry]

I have tried all 20 round P Mags. I have 8= 20 rd. P Mags. and all of them do the same thing, thay are brand new, never have been used.
kenner

How new is your rifle?
I want to say I've read about this, new rifles and new mags, not necessarily only an SR15/Pmag issue. Try cycling some rounds through the mags, manually if you have to, to break in the springs a bit.

[kenner]

My rifle is approx. 8 months old.
kenner