The 23 receiver is not compatible with the 38 slide.
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You will have to contact Glock for manufacturing data. Don't be
surpirsed if they don't provide it.
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There are several models of Glock pistol in .45 calibre. The .45 ACP models include the Glock 21, Glock 30, and Glock 36. The .45 GAP models include the Glock 37, Glock 38, and Glock 39. Factory standard magazine capacities are as follows: