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    ACCESSION NUMBER:		0001193125-25-196139
    CONFORMED SUBMISSION TYPE:	N-CSRS
    PUBLIC DOCUMENT COUNT:		14
    CONFORMED PERIOD OF REPORT:	20250630
    FILED AS OF DATE:		20250904
    DATE AS OF CHANGE:		20250904
    EFFECTIVENESS DATE:		20250904

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			BLACKROCK CORE BOND TRUST
    		CENTRAL INDEX KEY:			0001160864
    		ORGANIZATION NAME:
    		EIN:				522346891
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1031

    	FILING VALUES:
    		FORM TYPE:		N-CSRS
    		SEC ACT:		1940 Act
    		SEC FILE NUMBER:	811-10543
    		FILM NUMBER:		251293922

    	BUSINESS ADDRESS:
    		STREET 1:		100 BELLEVUE PARKWAY
    		STREET 2:		MUTUAL FUND DEPARTMENT
    		CITY:			WILMINGTON
    		STATE:			DE
    		ZIP:			19809
    		BUSINESS PHONE:		888-825-2257

    	MAIL ADDRESS:
    		STREET 1:		100 BELLEVUE PARKWAY
    		STREET 2:		MUTUAL FUND DEPARTMENT
    		CITY:			WILMINGTON
    		STATE:			DE
    		ZIP:			19809
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    <TYPE>N-CSRS
    <SEQUENCE>1
    <FILENAME>d21598dncsrs.htm
    <DESCRIPTION>BLACKROCK CORE BOND TRUST
    <TEXT>
    Document 1 - file: d21598dncsrs.htm

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    <DOCUMENT>
    <TYPE>EX-99.CERT
    <SEQUENCE>2
    <FILENAME>d21598dex99cert.htm
    <DESCRIPTION>CERTIFICATION PURSUANT TO SECTION 302
    <TEXT>
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    <TYPE>EX-99.906CERT
    <SEQUENCE>3
    <FILENAME>d21598dex99906cert.htm
    <DESCRIPTION>CERTIFICATION PURSUANT TO SECTION 906
    <TEXT>
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    <DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA
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    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
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    <TYPE>XML
    <SEQUENCE>9
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    <TEXT>
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    <TEXT>
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    <SEQUENCE>12
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    <TEXT>
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    <TEXT>
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    <TEXT>
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    <TYPE>XML
    <SEQUENCE>17
    <FILENAME>d21598dncsrs_htm.xml
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    <TEXT>
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