15 vs 16

I recently purchased a 16rd magazine for the P99. Though I've put a budgetary hold on my gun purchasing funds (due to other priorities), the price was too good to pass up. I've read that the P99 originally shipped with 16rd magazines, but the magazine was later redesigned to a 15rd capacity. This one is particular has a Walther-labeled baseplate, and was manufactured by Mec-Gar.

In case you're unfamiliar with the differences - and there are a couple - I thought a couple of pictures might be useful:



The lips at the top have been reshaped. The 16rd is on the left, the 15rd on the right. Note the more angular cut on the left. I'm not sure if this modification has any effect on feeding the rounds (my tests show no difference), but it does make loading the mags more difficult for sure. The first round is especially harder to quickly insert and seat onto the follower.

The cases themselves have differing vertical indentations, but I've no idea if these differences affect the mags' reliability.

The springs are different as well:



The 15rd (top) has a standard uniform coil, while the 16rd (bottom) has a staggered coil approximately 1/5 down from the top.

Curiously, I've been unable to load 16 rounds into the magazine. I'm not sure if it's due to a spring issue (perhaps it was replaced by the previous owner), or if it's naturally difficult to get the 16th round in - something you'll notice in Glock magazines, when they are new.

Because the magazine will only be used for range trips, I'm not too concerned about the unexpected capacity limit. It was a great deal, and it will do the job just fine. But if you're in the market for a used mag, hopefully this might give you a bit more info on the fact that the 16's and 15's are quite different in construction.