For those of you who collect this caliber, you might want to go through your collection of Chinese Rubber Filled Dummies. Russ Cornell tipped me off to the fact that 80% of the ones that look like black rubber are actually translucent dense Red or Blue. Some are actually Black, but most are not. The “gray” ones are actually Greenish or Whitish. If you put a strong pen-light behind them you will see the translucent color. The “black” ones will only show the true color in the last 1/8 inch or so of the bullet, but the “gray” are translucent all the way to the casemouth.
Boy, just when I thought I was getting a handle on these 7.62x39’s something else comes to light (pun intended).