I had the same problem with Remington Golden Bullets. The first 8, or so, rounds. Have you tried Ruger’s BX25 mags? They brag on the angle of the feed lips...same as the factory 10 rounders.
I have, and they are not 100% reliable with the 60gr SS.
That’s no problem, the 60gr is for long range plinking, so ten at a time is plenty. Minute of man at 200 yards easy, using a scope.
I had the chance in the boonies a while back to compare the following:
AR-15 supersonic 5.56mm, suppressed and unsuppressed.
Ruger 10-22 supersonic and subsonic 22LR, suppressed and unsuppressed. (The same name-brand can fit on both rifles.)
Here’s what we found. The sonic crack of a suppressed 5.56 is still about as loud as an unsuppressed supersonic 22LR. (But at least it doesn’t give away your position.)
Firing supersonic 22LR from a suppressed 16” barrel is still pretty loud. You still have that sonic crack.
Firing subsonic 22LR from the same barrel is pretty quiet even with no suppressor attached. Our conclusion: at least half of the noise signature from a 22LR is sonic crack. Going subsonic takes away half of the noise right away.
Firing the subsonic 60gr from a suppressed barrel is truly silent. I have air guns that make more noise. Only the bolt is audible. This conclusion was expected.
The real surprise was how quiet the 22LR subsonic is from a rifle barrel, even unsuppressed. You can fire it in suburbia no problem. A carpenter makes more noise with a hammer.