A little research goes along way
The first batch of IHC M1s produced were probably Arrowheads, followed by SA Postage Stamps. The receivers were bought from SA as an interim measure to meet production schedules while IHC solved the “failure to feed” problem. A number of these will have SA barrels furnished with the receiver. Both the Arrowheads and the SA/IHC Postage stamps were produced in 1953.#
The SA Postage Stamp production seems to be intermingled with the Arrowhead variation and the early generic IHC Postage Stamps with no true pattern. The SA/IHC Postage Stamp is considered to be the rarest variation, with the SA/IHC Arrowhead running a very close second. Except for the very experienced eye, the SA/IHC and the IHC/IHC Postage Stamp must be removed from the stock for positive identification.
Generic IHC Postage Stamp Logos, most common of all IHC variations. Note that the heat-lot of the IHC receivers is a letter following the drawing number. Easily told from the SA receivers due to the lack of the SA style heat-lot number/letter sequence. The earliest of these guns were apparently produced concurrently with SA/IHC Arrowheads and SA/IHC Postage Stamps during the production of the first 5000 to 6000 Rifles. Produced from 1953 to 1955
This is the most common of the “Gap Letter Guns”. Approximately 22,000 guns in this sequence. Note the SA heat lot number. IHC was randomly stamped in front of the 4 million serial number range drawing number. The IHC was dropped for the 5 million Gap Numbered Guns. The 4 M Gap Lettered guns were produced (approximately) between Nov. 1953 and Feb. 1954.
Essentially the same as the 4 million Gap Numbered Guns. The “IHC” was dropped from the Drawing Number of the 5 million Serial Number Range Guns. More rare than the 4 million guns, this range is more clearly defined, and consists of 13,243 rifles. Produced from 1955 to very early 1956.
HRA manufactured receivers purchased by IHC at the end of IHC production. Notice the widely spaced typical HRA marking on the receiver leg, along with the separate heat-lot letter. End of the range is not clearly defined. Produced from 1955 to very early 1956.
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