Bought a gen 5 26 with night sights a year ago. Maybe longer? Ive shot 2900 round thru it. Today I put 100 rounds of sellier and bellot 115 fmj ammo thru it. It was shooting very well. Was working at 25 yard targets. Then all the sudden it slidelocked open with a loaded mag. I was shooting five shot groups. Then shot about 10 more rounds. It did it again. Then approx. 30 more rounds. 7 or 8 times in a row. It happened 12 or 13 times out of 100 rounds fired today. I have been shooting different generations of the model 26 for at least a year and a half or 2 years. No other guns really. Maybe a different glock model here and there? I shoot every week. Always works. Clean the gun after shooting it. Use the same magazine, it works. Its got a hyve baseplate +2 on it. I wipe the magazine down every range session. Mag was included with a 2nd magazine, and a used glock 26.3 gun. The magazine has about 10,000 rounds i have shot out of it. I use it only, pretty much. Sometimes I use a +2 glock factory magazine. I had no other gun or parts, or magazines today to swap. I forgot my 2nd 26.3 and another +2 magazine. Just in case this was to happen. If its not broke dont fix it. But its a glock, and now its broke! The slidelock just locks open on a loaded magazine. Flip it, it loads extracts, and ejects just fine. If I wanted a single shot I would have bought a rifle. Any ideas, anybody?