-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 DqD1PTs6ULTn4JJmV6L89X5cvbItund4PBidiaxbNDPZm4YgFOGvDOjiUIWSHhN0
 aATLhs8Z8VXJo9rXKv8JvQ==

<SEC-DOCUMENT>0001181431-05-025777.txt : 20050504
<SEC-HEADER>0001181431-05-025777.hdr.sgml : 20050504
<ACCEPTANCE-DATETIME>20050504182413
ACCESSION NUMBER:		0001181431-05-025777
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050426
FILED AS OF DATE:		20050504
DATE AS OF CHANGE:		20050504

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MCINTOSH JOHN L
		CENTRAL INDEX KEY:			0001220617

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-01070
		FILM NUMBER:		05800669

	BUSINESS ADDRESS:	
		STREET 1:		OLIN CORP
		STREET 2:		501 MERRITT 7
		CITY:			NORWALK
		STATE:			CT
		ZIP:			06856
		BUSINESS PHONE:		2037503795

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			OLIN CORP
		CENTRAL INDEX KEY:			0000074303
		STANDARD INDUSTRIAL CLASSIFICATION:	ROLLING DRAWING & EXTRUDING OF NONFERROUS METALS [3350]
		IRS NUMBER:				131872319
		STATE OF INCORPORATION:			VA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		OLIN CORP
		STREET 2:		190 CARONDELET PLAZA SUITE 1530
		CITY:			CLAYTON
		STATE:			MO
		ZIP:			63105
		BUSINESS PHONE:		3144801400

	MAIL ADDRESS:	
		STREET 1:		OLIN CORP
		STREET 2:		190 CARONDELET PLAZA SUITE 1530
		CITY:			CLAYTON
		STATE:			MO
		ZIP:			63105

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	OLIN MATHIESON CHEMICAL CORP
		DATE OF NAME CHANGE:	19691008
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd77821.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-04-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000074303</issuerCik>
        <issuerName>OLIN CORP</issuerName>
        <issuerTradingSymbol>OLN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001220617</rptOwnerCik>
            <rptOwnerName>MCINTOSH JOHN L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>OLIN CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>490 STUART RD. N.E.</rptOwnerStreet2>
            <rptOwnerCity>CLEVELAND</rptOwnerCity>
            <rptOwnerState>TN</rptOwnerState>
            <rptOwnerZipCode>37311</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock $1 par vlaue</value>
            </securityTitle>
            <transactionDate>
                <value>2005-04-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1675</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>17.16</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2550</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock $1 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2005-04-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>875</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>21.37</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1675</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock $1 par value</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6370.0006</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By ESOP Trustee</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>17.16</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-04-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1675</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>1996-04-27</value>
            </exerciseDate>
            <expirationDate>
                <value>2005-04-26</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1675</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The figure shown represents shares of Olin Common Stock acquired on a periodic basis under the Olin Corporation Contributing Employee Ownership Plan (CEOP), a tax-conditioned plan, and held in the Olin Common Stock Fund of the CEOP, in a transaction exempt under Rule 16b-3, and is based on information provided by the Plan Administrator as of March 31, 2005.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/B. M. Pantalone, Attorney-in-Fact</signatureName>
        <signatureDate>2005-05-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----