Hawg is right. If they fire on the second go around, the caps are too tight.
Most ROA shooter's I know have trigger jobs done. Rugers are notorious for a stiff trigger. I thought this could be your issue (spring too light). However, since they are firing the second time around, I agree with Hawg.
FWIW If your Ruger has ever been modified in any way, DO NOT send it back to Ruger. I had a friend who had some trigger work done and sent it to Ruger for a sight adjustment. He had ONE HECK OF A TIME GETTING IT BACK FROM THEM! They said it was modified and unsafe. (because of the light trigger).
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