WE PDW doesn't like Pmags?

[James's]

Hiya folks.
I got a PDW a few months back and then managed to unclip my sling while throwing a grenade, unleashing the power of gravity on its second skirmish!
All was fine except the stock latch broke on the lower receiver so I got a replacement lower.

**I had noticed before this incident that the WE pmags fit so snuggly there's no wobble at all, but it didn't sound quite the same when using them. More on this point shortly.**

Replaced the lower and test fired a few shots using a stanag m4 magazine. Perfect working order. Nice cycle. Magazine flops around a bit as it used to, but has a good seal while the bolts forward.

The pmags however, needed a good slap to seat the magazine, it cycled slowly as if there was resistance, and sounded like a wet fart.

Turns out that fitting perfectly in the mag well of a PDW creates too much pressure between the loading nozzle and magazine seal.
It's all of around 0.5mm difference, but you can see how the stanag in the first picture is dipping forward, where the pmag in the second photo is running perfectly in line with the reciever.





Has anyone got any suggestions of how I could resolve this issue without resorting to new magazines?
I also run a WE scar using these pmags too, so would rather the modification was on the lower reciever; which is the only thing that's changed so I'm sure it's to blame....

I'd love to solve this, it's a cracking gun and I really enjoyed playing with it but it needs to see more than two games!

Many thanks in advance.
Jim

[James's]

WE PDW doesn't like Pmags?

**Issue solved without any material removal**

I had overlooked the guide rails that the bolt slide up and down....
Removed and cleaned the two thin lengths of steel and then visually inspected. I've got a very keen eye and noticed that the threaded holes in each bar were off centre by a barely measurable amount.
They had been previously installed in a configuration that would have made my problems worse, pushing the bolt down onto the magazine more than it needed to be, so I corrected them.

Now it operates flawlessly with all of my pmags, with no bolt resistance, and a perfect seal.

I'm over the moon!