Bf109K-4 Armament.

[Clayton Magnet]

Im sure this has been covered in the past, but I would appreciate some clarification. Some sources state it carried two MG 151/15's in the upper cowl, but others claim two MG 131's.
Im fairly sure it was the latter, but i have even read pilot accounts confirming the 15mm cannon (my guess is a translation error). I cant imagine they could have shoe-horned a MG 151 into the machine gun bay of a G-10 and not have to redesign the cowl.

 

[Jabberwocky]

Im sure this has been covered in the past, but I would appreciate some clarification. Some sources state it carried two MG 151/15's in the upper cowl, but others claim two MG 131's.
Im fairly sure it was the latter, but i have even read pilot accounts confirming the 15mm cannon (my guess is a translation error). I cant imagine they could have shoe-horned a MG 151 into the machine gun bay of a G-10 and not have to redesign the cowl.

MG151/15 was 1917 mm long. MG 131 was 1170 long.

Unless you significantly changed the 109K cowling or buried the recievers in the cockpit, the MG151/15 would have protruded signifcantly from the armament groves (poor terminology, but I cant think of a better description at the moment). Plus the cowling would have needed to have been significantly bulged to house the much larger MG151/15 breech block (think the 109G5/6 style cheek bulges), and the ammunition feeds would have needed revision.

As there is no evidence of such major structural changes to the 109K and no pictures of cannon barrels protruding 60 or 70 cm out of the cowling, its pretty safe to conclude that the weapon was not fitted in replacement of the MG131.

 

[Denniss]

Common myth, someone mistook a 3 for a 5 so this myth was born. Installation was impossible in the 109 without major structural change.

 

[rinkol]

I've seen an MG 151/15 - it is definitely a massive gun.