I have all but figured this problem was a bad run of pins. I have had reputable gunsmiths agree with this. My mini 30 would only shoot brass and right now you can't find brass. I sent 30 in to ruger asking about steel ammo and they keep changing their stance on it. I digress they changed my firing pin and it fires everything now. Send it to ruger they will replace it and you should then be able to shoot the rest of days with it.also if you "got it" in past year they pay shipping. Money saving tip