I have long been interested in FN’s 5.7mm cartridge. It’s a throated pistol round with very interesting ballistic performance. It’s a scratch-built round, an unusual situation in this day and age.

The FN P90 individual weapon has also caught my eye for a long time; I was, and am not, thrilled by the bullpup concept, but given the P90s unique magazine placement, I was not so quick to condemn the design, although I had a very strong suspicious that I would shoot my left hand off if I used one.

Despite that concern, I finally got around to renting one, and running a hundred rounds through it.

Now, the P90 certainly looks cool, and the 5.7mm round in very impressive, and FN’s quality is unchallenged. But when I actually got my hands on the weapon, I was not impressed. It feels like a toy, and not in a good way: it feels flimsy. Now, I’m not one of the ‘steel and hardwood’ purists, although I am of that generation, but I want a weapon to feel like a weapon, and the P90 felt like plastic and junk.

The integral optic sight is awful; luckily you are literally looking down the barrel. There is no selector switch; instead, you have a two-stage trigger, pull to the first stage for semi, long draw for full auto. And this with a trigger action that a barnyard gate could match. Its not a hard pull for either, but it is a loooonnnnggg draw for either. I would hate to use the P90 up close where fast reactions count for a lot.

Firing was nice enough, there’s not much felt recoil, and at pistol ranges you can put the round where you want it, even with the crappy optic sight. I did not shoot my left hand off, BTW.

But the ergonomics were not good for me. I felt hunched and my arc of view constrained, which is not a good thing at the ranges the P90 is designed for. Close-in snap-shooting without sights, or using a laser, is not a comfortable fit with the P90s design, and its boxy, plank-shaped construction makes releasing your off-hand to open a door or similar task problematic, and also can place your left hand out in front of your muzzle.

Overall, it was a disappointment. An MP-5 with a good sling would give the user far more options and ease of use, albeit with the less effective 9mm rounds, but I feel the greater arc of vision and better trigger control would be worth it. An M-4 is longer, but I believe would sill out-perform the P90 at close quarters due to ergonomics and vision.

If you were going to deploy the P90, it would require extensive re-training and practice to bring users up to a basic proficiency. Frankly, I would suggest using the round in the AR-57 configurations, which is just a M-4 chambered for 5.7mm.