The 49/56 firing pin is 'free-floating' within the bolt. The heavy MAS pin was designed to impact French Milspec 7.5x 54mm ammo with tough combat primers-ie: with considerable force. Modern commercial ammunition and reloads have "softer" primers because they are sufficient for civilian use. The heavy steel MAS 49/56 firing pin exhibits sufficient forward inertia when the bolt is released to impact and detonate sensitive commercial primers. (This all happens without pulling the trigger.)
Various unwanted occurrences can result: Slam fires (a round is hurled down the barrel when the bolt is released), burst fire (a couple of rounds fire off to the great surprise of the shooter or
full auto-the weapon just rocks and rolls on until the mag is empty.
Titanium firing pins have proven to be the most direct cure for embarrassing and potentially dangerous slam, burst and/or auto fire in MAS 49/56 rifles using commercial ammo with soft primers.
A Place to order a new titaninum firing pin.
http://www.google.com/url?sa=t&source=web&cd=1&ved=0ahUKEwiFkLOBz5vQAhVi VWMKHez3B_MQFggaMAA&url=http%3A%2F%2Fphillittlegun s.com%2F&usg=AFQjCNG_YGcJbAtIO1F6ZvCA3nrb_OW3SA&si g2=zh0w4OUw_5iNfkrH_tuNXA
For the price of a new Titanium its still cheap insurance against a future (liable) potential slamb fire and the consequential damage and or death that can result if a round or burst goes off accidentally at the firing range.