A big change in magazine production was implemented after April 1942 (ac42 d-block). From that point on, magazines no longer were serial-numbered to the pistol. Another change that occurred at the same time was that the smaller magazine parts no longer were marked with the Walther E/359 acceptance stamp. The markings on the spine also were changed from two E/359 acceptance stamps to just one E/359 acceptance stamp. This stamp can be found high on the spine. These magazines were provided with pistols produced from May 1942 until February 1943.
Transition variations from the serialized ac42 magazines to the un-serialized magazines also exist. There were probably still a lot of older type parts in stock during the transition to the new magazine variation and these were also used up as the germans were not in a position to waste any material. Therefore magazines exist that have features of both the older and the new variation and those magazines are therefore called the transition variation. Transition magazines are mainly observed with P.38 pistols produced by Walther around May 1942 (d-block) but are also found in a lower frequency with later pistols. Two transition magazines are shown here.
The first transition magazine has one Walther acceptance stamp E/359 on the spine. This would be correct for the magazine used after April 1942. However the E/359 marking is stamped very low on the spine in contrast to other magazines of this type. The follower is also stamped with E/359 and that indicates that this magazine is probably built up from left over parts from the previous variation. I think that this magazine housing was meant to be double E/359 stamped, but the second E/359 (high on the spine) was never applied due to the change to the new variation where only one E/359 was used.
A second transition magazine is shown below. It has two E/359 Walther acceptance stamps on the spine and at first sight this magazine looks like the well-known magazine variation that was issued with Walther pistols from the beginning of 1941 till April 1942. But in that case there should be a serial number on the floorplate and all the internal parts should be stamped with the walther acceptance stamp.
This magazine doesn't have a serial number and only the follower is stamped with E/359. Starting from May 1942, magazines were no longer stamped with serial numbers and the internal parts were no longer applied with an acceptance stamp. Also the spine was from this point stamped with only one E/359 acceptance stamp instead of two. This example has a magazine housing and a follower that are of the older type (double E/359 stamp on the magazine housing).