Remington 1903a3 / 1903a4 cartouche stock questions

I NOTICE THE UNBOXED FJA AND BOXED FJA CARTOUCHES BOTH APPEAR ON 1903A3 AND 1903A4 RIFLES. DID ONE COME BEFORE THE OTHER OR WERE THEY BOTH USED AT THE SAME TIME? IF THERE WAS A TIME FRAME DIFFERENCE DOES ANYONE KNOW THE SERIAL NUMBER RANGES WHEN THESE 2 DIFFERENT FJA CARTOUCHES WERE USED? ALSO ON NEW PRODUCTION {NOT REBUILDS}1903A4 SNIPER RIFLES WERE FULL PISTOL GRIP AND SCANT GRIP STOCKS USED AT THE SAME TIME OR ONE BEFORE THE OTHER? THE 2 RIFLES IN QUESTION ARE SER #s 3,42x,xxx and 4,99x,xxx. THANKS IN ADVANCE.

Answers are as follows:

(1) Yes and Yes.
(2) Yes
(3) One before the other with a small overlap.

J.B.