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  <xs:element id="cmpo_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmpo_RevenuePerformanceObligationPaymentDue" abstract="false" name="RevenuePerformanceObligationPaymentDue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cmpo_LesseeOperatingLeaseBaseRent" abstract="false" name="LesseeOperatingLeaseBaseRent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmpo_AssetsAndLiabilitiesLesseeTableTextBlock" abstract="false" name="AssetsAndLiabilitiesLesseeTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmpo_DefinedContributionPlanMatchingScenarioDomain" abstract="true" name="DefinedContributionPlanMatchingScenarioDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmpo_DebtInstrumentConvertibleRegistrationDefaultInterestRateForFirst90Days" abstract="false" name="DebtInstrumentConvertibleRegistrationDefaultInterestRateForFirst90Days" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="cmpo_RestrictedStockUnitsAndPerformanceSharesMember" abstract="true" name="RestrictedStockUnitsAndPerformanceSharesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmpo_CreditFacility2016Member" abstract="true" name="CreditFacility2016Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmpo_CommonStockRedemptionValue" abstract="false" name="CommonStockRedemptionValue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmpo_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cmpo_DeferredCompensationArrangementWithIndividualVestingPercentageYearOne" abstract="false" name="DeferredCompensationArrangementWithIndividualVestingPercentageYearOne" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
