I’ll admit it, I am guilty of at least two of these (though not the common ones). OutdoorHub has posted up a video on ten gun companies, names, and models that are commonly mispronounced. The video is decidedly cheesy, but includes pronunciation from native speakers in the firearms’ home language.
Full list includes:
• Mosin
• Steyr
• Kalashnikov
• Garand
• Dragunov
• Sturmgewehr
• Tavor
• Heckler Und Koch
• Makarov
• Saiga
Thanks to GlockForums for the title photo!