Yes I wasn't too concerned about it. If it had happened several times I'd be a little annoyed but once is 300 rounds of mixed ammunition is reasonable. The BB that I was using is older stock I have and I noticed yesterday the slide doesn't slam forward as hard when releasing the slide lock like it does with the other stuff I was using. I may check a couple of rounds today to see if they're slightly out of spec. I really like the gun though. Wish it had a few more cosmetic bells and whistles but then again that adds cost so it defeats the purpose.I wouldn't even give that a second thought unless it happened after 500. The pistol is tightly fit, and the parts need time/use to adjust to each other....
Im going to leave it as is. Mine has been running great with all issues worked out the more I shot it. Seems like it didn't like 115 grain Fiocchi ammo at first. Now it eats it no problem. The thing that cracks me up is I read a review on this gun and they used Fiocchi ammo to test it. The guy who did the testing said Fiocchi ran great. When I asked Ed Brown customer service they told me they never heard of Fiocchi.With the exception of the 1 FTRTB I haven't had any hiccups. I've purposely used several different manufactures and weights and it's been running great. Personally I don't plan on changing anything.