Exhibit 99.1

    GenCorp Announces Private Offering of Convertible Subordinated Debentures

    SACRAMENTO, Calif., Nov. 8 /PRNewswire-FirstCall/ -- GenCorp Inc.
("GenCorp") (NYSE: GY) today announced that it will offer $50 million of its
convertible subordinated debentures due 2024 in a private placement.  The
debentures will be convertible, at the option of the holder upon the
satisfaction of certain conditions, into cash and the Company's common stock.
The interest rate, conversion price and offering price are to be determined by
negotiations between the Company and the initial purchasers of the debentures.
The Company will also grant the initial purchasers an option to purchase up to
an additional $25 million aggregate principal amount of debentures.
    The Company expects to use the net proceeds of the offering to repurchase
a portion of its 5 3/4% convertible subordinated notes in privately negotiated
transactions concurrently with, or subsequent to, the closing of this
offering.  Any proceeds not used to repurchase the Company's 5 3/4%
convertible subordinated notes will be used to repay or repurchase other
outstanding indebtedness.
    This announcement shall not constitute an offer to sell or a solicitation
of an offer to buy nor shall there be any offer of these securities in any
state in which such offer, solicitation or sale would be unlawful.
    The debentures and the common stock issuable upon conversion have not been
registered under the Securities Act of 1933, as amended, or applicable state
securities laws, and are being offered only to qualified institutional buyers
in reliance on Rule 144A under the Securities Act.  Unless so registered, the
debentures and common stock issued upon conversion of the debentures may not
be offered or sold in the United States except pursuant to an exemption from
the registration requirements of the Securities Act and applicable state
securities laws.  The Company has agreed that it will file a registration
statement covering the resale of the debentures and the common stock issuable
upon conversion of the debentures.

    About GenCorp
    GenCorp is a leading technology-based manufacturer of aerospace and
defense products and systems with a real estate business segment that includes
activities related to the development, sale and leasing of the Company's real
estate assets.  Additional information about the Company can be obtained by
visiting the Company's web site at http://www.GenCorp.com.

    Forward-Looking Statements
    This press release contains forward-looking statements based on current
management expectations.  Numerous factors, including those related to market
conditions and those detailed from time to time in GenCorp's filings with the
Securities and Exchange Commission, may cause results to differ materially
from those anticipated in the forward-looking statements.  Many of the factors
that will determine GenCorp's future results are beyond the ability of GenCorp
to control or predict.  These statements are subject to risks and
uncertainties and, therefore, actual results may differ materially.  Readers
should not place undue reliance on forward-looking statements, which reflect
management's views only as of the date hereof.  GenCorp undertakes no
obligation to revise or update any forward-looking statements, or to make any
other forward-looking statements, whether as a result of new information,
future events or otherwise.

SOURCE  GenCorp Inc.
    -0-                             11/08/2004
    /CONTACT:  investors, Yasmin Seyal, senior vice president & chief
financial officer, +1-916-351-8585, or press, Linda Beech Cutler, vice
president, corporate communications, +1-916-351-8650, both of GenCorp Inc./
    /Web site:  http://www.gencorp.com/
    (GY)

CO:  GenCorp Inc.
ST:  California
IN:  ARO RLT
SU:  ACC