With the pin file down an it ah beat rapid
On some semi-automatic weapons it is possible (or believed to be possible) that filing down the end of the firing pin a little can turn a semi-automatic into a fully automatic weapon (or often the best you will get is doubling and some triples, not quite full auto but close). This is what Marley is referring too, saying this is what the thugs have done to their guns.
However, do note that on the vast majority of weapons filing down the firing pin will shorten it to the point it can no longer reach the primers, turning your weapon into a non-firing one — not very close to full auto at all. Not to mention altering a firearm in this way is very ILLEGAL in most jurisdictions.
Bolts of a semi and a full auto Uzi, the absence of a lower lip on the semi bolt face (highlighted) allows the exposed firing pin to contact the rim of a case during feeding, causing it to jam (not full-auto).
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