I agree with That coin dude, what you are seeing is
Die Deterioration Doubling.
However, 1964, 1965, and 1966 nickels all have a minor Doubled Die Reverse, I would say at least over half of the reverse dies for each year show a small spread of hub doubling which makes it actually fairly common.
For 1964 - You should be able to find a small split in the tip of the stem of the left leaf on the reverse and the tip of the 6 in the date.
for 1965 - You should be able to find a small split in the tip of the stem on the left leaf and the right leaf, along with "5 Cents".
for 1966 - You should be able to find a small split in the tip of the stem on the left leaf and the tips of the "66" in the date.
The only
DDR for those 3 years worth keeping if found is the 1965
DDR Doubled 5 that shows a moderate spread of hub doubling on the "5" in the date.
Finding and discovering modern Canadian doubled die varieties since 2018.
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Modern Canadian Doubled Die Varieties - First Edition
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