The business of bundling riskier U.S. mortgages into bonds without government backing is gearing up for a comeback. Just don’t call it subprime.

Hedge fund Seer Capital Management, money manager Angel Oak Capital and Sydney-based bank Macquarie Group Ltd. are among firms buying up loans to borrowers who can’t qualify for conventional mortgages because of issues such as low credit scores, foreclosures or hard-to-document income. They each plan to pool the mortgages into securities of varying risk and sell some to investors this year. JPMorgan Chase & Co. analysts predict as much as $5 billion of deals could get done, while Nomura Holdings Inc. forecasts $1 billion to $2 billion.