The Grigorovich M-16 was a variant of the Grigorovich M-9 with floats and developed to operate in winter conditions. It became a very important WWI-era plane for Russia, and, ironically, Finland. It’s primary role was as a reconnaissance plane, though it did have a variant called the GASN which was a torpedo-bomber.
The Colt M16 rifle is the military variant of the AR-15 first developed by ArmaLite in 1959. By the late 1960s it was the standard issue infantry rifle for the US armed forces. It is still in use by Navy and Marine forces.
The only logical question, then, is, “How do they compare?”