CZ sp-01 shadow custom ejection problem

[MP9]

I got a new sp-01 shadow custom last month.. lI have ess than 1200 rounds through it.

bayou 147gr FP. OAL .1.120 - 1.130.. mixed brass

I dont know what may be happening or what I'm doing wrong. This happened in the last 2 matches (idpa) in one stage on each..

the extractor is clean, the ejector looks the same as my sp-01 standard.. (mc gar mags)I wasnt using the factory ones until I replace the spring (+10%)

this occur only after a slide lock reload.. I insert the fresh mag.. close the slide.. fired a round and it wont eject the case.. there was a round in the chamber and the case was in the middle, an stovepipe..

in the last match I inserted the fresh mag, closed the slide and it didnt go fully into battery, racked it and fire...another stovepipe..I removed the mag and inserted the other one..

once I finished the stage I checked the mag and the round on top was facing down...

this ONLY happen after I do a slide lock reload...otherwise the gun works without issue.. I was using mc-gar mags.

I will try to get myself recorded while shooting the stage, sometimes I close the slide too soon so not round get in the chamber.. in that case I just rack and continue shooting.. but other times maybe I close it just a little too soon where it still try to chamber the round but somehow it get stuck in the middle pushing maybe the next round down or kind of double feed, causing then the failure to eject..(not sure how)

I went to the range and fired 400 rounds... mostly inserting a fresh mag with 2 or 3 6 rounds, closing the slide . to see If I could get the same issue...0 problem.

any idea? I read somewhere this could be the slide the dragging the next round and causing kind of double feed, ejection problems...? if so, why this only happen after a new reload?

can this happen if I insert the mag too hard?

there shouldnt be any problem with 147gr FP bullets right? I am thinking getting some RN to see if that helps..

thanks

[GrumpyOne]

Polish the underside.of the slide. The jam won't clear until you drop the mag, right?

[CeeZer]

Top round nose diving may be caused by broken front 'leg' of the mag follower and/or weak mag spring.

[emjei]

Is your Slide Stop grinded for long bullets? ?

Mj

[MP9]

yes it is grinded. I compared it to my standard sp-01.

mc gar are like 1 year old.. not so much usage though.. will replace the springs and polish underside of the slide too.