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  <xs:element id="gpgi_NetIncomeLosses" abstract="false" name="NetIncomeLosses" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_AdjustmentsToAdditionalPaidInCapitalDeemedDividendForShareBasedCompensationToResoluteEmployees" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalDeemedDividendForShareBasedCompensationToResoluteEmployees" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_UnrealizedGainLossOnDerivativesInterestRateSwap" abstract="false" name="UnrealizedGainLossOnDerivativesInterestRateSwap" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_AdjustmentsToAdditionalPaidInCapitalSpinOff" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalSpinOff" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_AdjustmentsToAdditionalPaidInCapitalDeconsolidation" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalDeconsolidation" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_NonCashOperatingLeaseExpense" abstract="false" name="NonCashOperatingLeaseExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_PaymentsForHoldingsNetAssetsDeconsolidated" abstract="false" name="PaymentsForHoldingsNetAssetsDeconsolidated" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_PaymentForResoluteCashAtSpin" abstract="false" name="PaymentForResoluteCashAtSpin" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_PaymentOnTaxReceivableAgreementLiability" abstract="false" name="PaymentOnTaxReceivableAgreementLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_NonCashInterestCarryforward" abstract="false" name="NonCashInterestCarryforward" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_StockIssuanceCostsIncurredButNotYetPaid" abstract="false" name="StockIssuanceCostsIncurredButNotYetPaid" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_NonCashChangeInDerivativeAsset" abstract="false" name="NonCashChangeInDerivativeAsset" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_NonCashPortionOfWarrantExercise" abstract="false" name="NonCashPortionOfWarrantExercise" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_NonCashContributionForStockBasedCompensation" abstract="false" name="NonCashContributionForStockBasedCompensation" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_GPGIHoldingsNetLiabilitiesExcludingCashAndCashEquivalentDeconsolidated" abstract="false" name="GPGIHoldingsNetLiabilitiesExcludingCashAndCashEquivalentDeconsolidated" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_ResoluteHoldingsNetLiabilitiesExcludingCashAndCashEquivalentDeconsolidatedAsResultOfSpinOff" abstract="false" name="ResoluteHoldingsNetLiabilitiesExcludingCashAndCashEquivalentDeconsolidatedAsResultOfSpinOff" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementMaturityTableTextBlock" abstract="false" name="TaxReceivableAgreementMaturityTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gpgi_Tungsten2024LLCMember" abstract="true" name="Tungsten2024LLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_CompoSecureHoldingsL.L.CMember" abstract="true" name="CompoSecureHoldingsL.L.CMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_NumberOfMarketLeadingBusinesses" abstract="false" name="NumberOfMarketLeadingBusinesses" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="gpgi_SaleOfStockNumberOfSharesExchangedInTransaction" abstract="false" name="SaleOfStockNumberOfSharesExchangedInTransaction" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gpgi_SaleOfStockPercentageOfOwnershipAcquiredDuringTransaction" abstract="false" name="SaleOfStockPercentageOfOwnershipAcquiredDuringTransaction" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gpgi_SaleOfStockConversionRatio" abstract="false" name="SaleOfStockConversionRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="gpgi_ManagementFeePercentage" abstract="false" name="ManagementFeePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gpgi_ManagementAgreementInitialTerm" abstract="false" name="ManagementAgreementInitialTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="gpgi_ManagementAgreementRenewalTerm" abstract="false" name="ManagementAgreementRenewalTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="gpgi_EquityMethodInvestmentsRollForward" abstract="true" name="EquityMethodInvestmentsRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="gpgi_EquityMethodInvestmentsStockBasedCompensation" abstract="false" name="EquityMethodInvestmentsStockBasedCompensation" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_EquityMethodInvestmentsEarningsLosses" abstract="false" name="EquityMethodInvestmentsEarningsLosses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_EquityMethodInvestmentsCashTransaction" abstract="false" name="EquityMethodInvestmentsCashTransaction" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_EquityMethodInvestmentsEquityTransaction" abstract="false" name="EquityMethodInvestmentsEquityTransaction" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_EquityMethodInvestmentsContribution" abstract="false" name="EquityMethodInvestmentsContribution" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_EquityMethodInvestmentsAdvanceToAffiliate" abstract="false" name="EquityMethodInvestmentsAdvanceToAffiliate" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_PIPEPurchaseAgreementMember" abstract="true" name="PIPEPurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_WarrantsMember" abstract="true" name="WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_WarrantsOrRightsOutstandingRedemptionPricePerShare" abstract="false" name="WarrantsOrRightsOutstandingRedemptionPricePerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="gpgi_ContractorAgreementsMember" abstract="true" name="ContractorAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_LongTermIncentivePlanAwardsMember" abstract="true" name="LongTermIncentivePlanAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_PerformanceIncentiveProgramPeriodAxis" abstract="true" name="PerformanceIncentiveProgramPeriodAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="gpgi_PerformanceIncentiveProgramPeriodDomain" abstract="true" name="PerformanceIncentiveProgramPeriodDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_A2026TargetHuskyAdjustedEBITDAMember" abstract="true" name="A2026TargetHuskyAdjustedEBITDAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_A2027TargetHuskyAdjustedEBITDAMember" abstract="true" name="A2027TargetHuskyAdjustedEBITDAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_A2028TargetHuskyAdjustedEBITDAMember" abstract="true" name="A2028TargetHuskyAdjustedEBITDAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_A2029TargetHuskyAdjustedEBITDAMember" abstract="true" name="A2029TargetHuskyAdjustedEBITDAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_PercentageOfAggregateNumberOfShares" abstract="false" name="PercentageOfAggregateNumberOfShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationDuration" abstract="false" name="PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationDuration" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization" abstract="false" name="PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardPercentage" abstract="false" name="PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardValue" abstract="false" name="PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="gpgi_EarnoutConsiderationMember" abstract="true" name="EarnoutConsiderationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiabilityToBePaidTaxBenefitsPercentage" abstract="false" name="TaxReceivableAgreementLiabilityToBePaidTaxBenefitsPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiabilityPaid" abstract="false" name="TaxReceivableAgreementLiabilityPaid" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiabilityToBePaidMaturityAbstract" abstract="true" name="TaxReceivableAgreementLiabilityToBePaidMaturityAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiabilityToBePaidRemainderOfFiscalYear" abstract="false" name="TaxReceivableAgreementLiabilityToBePaidRemainderOfFiscalYear" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiabilityToBePaidYearOne" abstract="false" name="TaxReceivableAgreementLiabilityToBePaidYearOne" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiabilityToBePaidYearTwo" abstract="false" name="TaxReceivableAgreementLiabilityToBePaidYearTwo" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiabilityToBePaidYearThree" abstract="false" name="TaxReceivableAgreementLiabilityToBePaidYearThree" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiabilityToBePaidYearFour" abstract="false" name="TaxReceivableAgreementLiabilityToBePaidYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiabilityToBePaidAfterYearFour" abstract="false" name="TaxReceivableAgreementLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_TaxReceivableAgreementLiability" abstract="false" name="TaxReceivableAgreementLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_SegmentReportingInformationCorporateAdjustedEBITDA" abstract="false" name="SegmentReportingInformationCorporateAdjustedEBITDA" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_Material" abstract="false" name="Material" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_Personnel" abstract="false" name="Personnel" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_SalesAndMarketingExpenses" abstract="false" name="SalesAndMarketingExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_NetIncomeLossAttributableToParentAdjustedEBITDA" abstract="false" name="NetIncomeLossAttributableToParentAdjustedEBITDA" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_CorporateAdjustedEBITDA" abstract="false" name="CorporateAdjustedEBITDA" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_FairValueInventoryStepUp" abstract="false" name="FairValueInventoryStepUp" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_MarkToMarketAdjustmentsNet" abstract="false" name="MarkToMarketAdjustmentsNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_SpinOffCosts" abstract="false" name="SpinOffCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_CompoSecureManagementAgreementMember" abstract="true" name="CompoSecureManagementAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_HuskyManagementAgreementMember" abstract="true" name="HuskyManagementAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_BoardAdviserAgreementMember" abstract="true" name="BoardAdviserAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_InvestorRightsAgreementMember" abstract="true" name="InvestorRightsAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_RegistrationRightsAgreementMember" abstract="true" name="RegistrationRightsAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gpgi_ManagementAgreementExpenses" abstract="false" name="ManagementAgreementExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_AnnualCashRetainerFee" abstract="false" name="AnnualCashRetainerFee" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gpgi_RelatedPartyTransactionSharePurchased" abstract="false" name="RelatedPartyTransactionSharePurchased" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gpgi_RelatedPartyTransactionBoardSeatsAboveTenPercent" abstract="false" name="RelatedPartyTransactionBoardSeatsAboveTenPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="gpgi_RelatedPartyTransactionOwnershipThresholdPercent" abstract="false" name="RelatedPartyTransactionOwnershipThresholdPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gpgi_RelatedPartyTransactionBoardSeatsAboveFivePercent" abstract="false" name="RelatedPartyTransactionBoardSeatsAboveFivePercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="gpgi_RelatedPartyTransactionLockupPeriod" abstract="false" name="RelatedPartyTransactionLockupPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="gpgi_RelatedPartyTransactionDemandRegistrationMeasurementPeriod" abstract="false" name="RelatedPartyTransactionDemandRegistrationMeasurementPeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
</xs:schema>
