A control valve for a handheld fluid meter, the control valve comprising: a valve cartridge comprising: a cartridge body extending between a first end and a second end of the cartridge body, the cartridge body including a first interior circumferential flow passage in the first end and a second interior circumferential flow passage in the second end; a radial inlet extending through the first end into the first interior circumferential flow passage; a radial outlet extending through the second end into the second interior circumferential flow passage; and a control seat disposed about an interior of the cartridge body between the first interior circumferential flow passage and the second interior circumferential flow passage; and a valve stem disposed in the valve cartridge, the valve stem comprising: an upper portion disposed within the first end, the upper portion including: an annular control seal groove; and a throttling portion extending below the control seal groove; a lower portion disposed within the second end, the lower portion including an actuation tip extending out of the second end of the valve cartridge; an elongate portion extending between and connecting the upper portion and the lower portion; and a control seal disposed in the control seal groove, the control seal configured to be engaged with the control seat with the valve stem in a closed position and to be disengaged from the control seat with the valve stem in an open position; wherein an annular flowpath is formed between the throttling portion and the control seat; and wherein a length of the annular flowpath varies as the valve stem transitions between the open position and the closed position. a valve cartridge comprising: a cartridge body extending between a first end and a second end of the cartridge body, the cartridge body including a first interior circumferential flow passage in the first end and a second interior circumferential flow passage in the second end; a radial inlet extending through the first end into the first interior circumferential flow passage; a radial outlet extending through the second end into the second interior circumferential flow passage; and a control seat disposed about an interior of the cartridge body between the first interior circumferential flow passage and the second interior circumferential flow passage; and a cartridge body extending between a first end and a second end of the cartridge body, the cartridge body including a first interior circumferential flow passage in the first end and a second interior circumferential flow passage in the second end; a radial inlet extending through the first end into the first interior circumferential flow passage; a radial outlet extending through the second end into the second interior circumferential flow passage; and a control seat disposed about an interior of the cartridge body between the first interior circumferential flow passage and the second interior circumferential flow passage; and a valve stem disposed in the valve cartridge, the valve stem comprising: an upper portion disposed within the first end, the upper portion including: an annular control seal groove; and a throttling portion extending below the control seal groove; a lower portion disposed within the second end, the lower portion including an actuation tip extending out of the second end of the valve cartridge; an elongate portion extending between and connecting the upper portion and the lower portion; and a control seal disposed in the control seal groove, the control seal configured to be engaged with the control seat with the valve stem in a closed position and to be disengaged from the control seat with the valve stem in an open position; wherein an annular flowpath is formed between the throttling portion and the control seat; and wherein a length of the annular flowpath varies as the valve stem transitions between the open position and the closed position. an upper portion disposed within the first end, the upper portion including: an annular control seal groove; and a throttling portion extending below the control seal groove; an annular control seal groove; and a throttling portion extending below the control seal groove; a lower portion disposed within the second end, the lower portion including an actuation tip extending out of the second end of the valve cartridge; an elongate portion extending between and connecting the upper portion and the lower portion; and a control seal disposed in the control seal groove, the control seal configured to be engaged with the control seat with the valve stem in a closed position and to be disengaged from the control seat with the valve stem in an open position; wherein an annular flowpath is formed between the throttling portion and the control seat; and wherein a length of the annular flowpath varies as the valve stem transitions between the open position and the closed position.