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The cancelled spec still on your print

AMS-QQ-C-320 turns up on legacy drawings all the time. It is cancelled. That does not mean your part is a problem — it means one conversation.

First, do not panic

If your drawing calls out QQ-C-320 or AMS-QQ-C-320 for chromium plating, you have a cancelled specification on your print. This is extremely common — the spec had a long life, and it is baked into decades of legacy drawings that are still in active circulation. We see it regularly.

A cancelled callout is not a dead end. It is a flag that says: confirm the current equivalent before plating, rather than plating blind to a spec no longer maintained.

What 'cancelled' actually means

A cancelled specification is one the issuing body no longer maintains or revises. It has usually been superseded by, or folded into, a current spec that carries the up-to-date requirements. The old number keeps appearing on drawings because updating every legacy print is a huge job that mostly never happens — so the callout outlives the document behind it.

For chromium plating, the current specifications we plate to are AMS 2460 and AMS 2406, each to its current revision.

What we do with it — and what we do not

What we do not do is quietly substitute a specification and say nothing. Silently swapping AMS-QQ-C-320 for whatever we think fits is how the wrong requirement ends up on a part, and on aerospace work that gets quoted back on an RFQ.

What we do: send us the print. We will work out the current AMS equivalent for your application with you, confirm it, and plate to that — so the decision is made deliberately and documented, not assumed.

Quick answers

Can you still plate my part if the print says QQ-C-320?: Yes. Send the print and we will establish the current equivalent with you, then plate to AMS 2460 / AMS 2406 as appropriate.
Will you just pick a replacement spec for me?: We will recommend one and confirm it with you — we will not substitute silently. On regulated work the specification has to be right and documented.