a truncated point is a small flat point instead of a wide flat point. the nose of the bullet tapers like a spire point and is abbreviated with a flat tip.
most flat point molds throw a bullet with a long wide point ahead of the driving bands and very little ogive.
most numbers trailing the caliber size and mold type number are there to designate the variation of that bullet.
i think! i have gotten to the age where i think i have forgotten about half of what i thought i knew! and i have some Ideal molds i bought brand new!