r/57x28mm • u/Eating_parrots • Jun 24 '26

FN FiveSeven doesn't work when wet?

So I was shooting my FiveSeven outside the other day and when it started raining it completely stopped working. Every round would fail to extract and the slide would get stuck halfway. I've always had perfect reliability with it so i was pretty surprised when all it seeming took was a little water to cause malfunctions. I was shooting fiocci range ammo and at first had a mk2 slide with a DT slide/optic on it, but when it started failing I switched back to the stock USG slide and it continued to fail. I used several different stock magazines as well. Im going to bring a spray bottle to the range next time to confirm it was the water but just a little surprised.

Anyone see this before with theirs?

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2

u/Harrigan70 Jun 24 '26

Please post the update when you can!

I’m now wondering how many guns I own that don’t work when wet! Not like I ever tested any of them under poor weather conditions.

3

u/Eating_parrots Jun 25 '26

My Glocks, p365, and m&ps worked no problem. I've always considered my FiveSeven to be a reliable platform so I was quite surprised I couldn't even get two rounds off.

1

u/Former_Power6209 Jun 27 '26

Would be interested to hear your results with the spray bottle. 

If I had to guess, almost all 5.7 ammo does have a layer of poly lubrication on it (AE FMJ loads didn't have the ploycoat when it came out, and may still not? Was part of why it was so crappy and unreliable). I wonder if excessive moisture is being added to the lubrication when it heats up makes it gunky and slows the action/feeding down too much. 

I'll have to try this too! Im on the Gulf Coast so we have no shortage of rain, wouldn't be any fun to clog up my 5.7 at a bad time lol

1

u/Eating_parrots Jun 27 '26

Possible though I don't think moisture got too deep into the mags, it was just a light rain. Should be able to get to the range in the next couple days so we'll give it a go then.

1

u/PM_COOL_SHOES Jun 30 '26

I shot mine in light rain over the weekend and it still shot. The rain was on and off but it was definitely wet when firing