u/Accurate-Side-8697

I'm using the CMMG 5.7 8" conversion with a traditional baffled can. I switched from the recommended standard buffer spring and carbine buffer to a Sprinco blue (+15% strength) buffer spring and an H2 buffer. After the first round in a mag, the bolt closes on an empty chamber. I assume mag friction is enough to slow the carrier that it is short stroking, but I'm not totally sure. I'm going to put a standard buffer spring in, but if anyone has experienced something similar and wants to save me the headache, please advise.