I put together a 9mm PCC using a CMMG RDB bolt/Carrier and barrel. I ultimately decided to upgrade the upper and bolt to the fixed ejector. I noticed that on the older bcg with the plunger ejector, the bolt is spring loaded in the carrier. The bolt is forced into its extended position by a spring, when the bolt isnt in battery.. On the new bcg that came with the fixed ejector upper, there is no spring forcing the bolt into its extended position. Is this a change that CMMG made or am I missing a spring?