It's also grabbed my attention. As far as I know MKEK is currently relocated all of its serial production capabilities and resources to produce MPT-76 and MPT-55 rifles like you see on the previous pics of the photoset and have not produced the HK-33E model for Turkish Army since 2011. Probably it's bought as a surplus for the G3s and kept in storage for years which is common for most of the non-operational and support units.
And also there is no additional modification on the gun apart from the MKEK made polymer 30rds magazine similar with the G36. It's has been used by the Turkish Military roughly for a decade.
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