A speed loader has an elongated planar body with opposed major faces, the elongated planar body defining a plurality of cartridge receptacles on one of the opposed major faces, each of the plurality of cartridge receptacles configured to removably retain the head of a cartridge, the plurality of cartridge receptacles arranged along the length of the elongated planar body in an articulated sequence, at least some of the plurality of cartridge receptacles being arranged in at least two obtuse triangular subgroups, each of the obtuse triangular subgroups having three different cartridge receptacles, and each obtuse triangular subgroup having two end cartridge receptacles proximate one major edge of the elongated planar body and an intermediate cartridge receptacle proximate an opposed major edge of the elongated planar body. The obtuse triangular subgroups may face the same major edge or opposite major edges. The obtuse triangular subgroups may each define an arc.