lancaster:

Sorry I missed this.

RE the CZ527, it possesses an engineering flaw in the design of the interface between the magazine and the action bottom whereby the correct location for feeding is governed by the stock dimensions - wood thickness - between the bottom metal which possesses the magazine latch and the action, where the bolt must reciprocate to provide proper feeding. Usually, the first round would feed, but #2 and #3 might lie too low and the bolt simply ride over them.

This problem seems to exist primarily with the 7.62x39 rifles. Some 527's feed just fine, or do for a while and then go to pot. I had one that was a frustration. CZ was very helpful and sent me new mags and springs but nothing would fix the gun. Had that problem not existed, it would have been a favorite of mine, but since it did, it is no longer mine!

I am not 100% certain that the magazine is not partially to blame.

At any rate, your ball detent idea just might solve the riddle and anything that can positively fix the magazine in position should eliminate the potential problem.

At any rate, a derailment off topic, I apologize, but I thought you might find that interesting.

And by the way, the project looks excellent. Bravo!!