The most common and most likely answer to this crossword clue is the 5 letter word GYRON
G
Y
R
O
N
Buddy explains!
The straight part
We know that "heraldic charge" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case heraldic charge = gyron.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GYRON mean?
GYRON noun- A triangular form having an angle at the fess point and the opposite side at the edge of the escutcheon.