Owner’s Manual 2020

12
For best results, use new factory manufactured ammunition from a
reputable manufacturer. Primers, powder, cartridge cases and bullets can
deteriorate with time and cause damage to the firearm or injury to the
shooter or others.
LEAD BULLETS HAVE A TENDENCY TO CAUSE BORE LEADING,
WHICH MAY DRAMATICALLY INCREASE PRESSURE WHEN A
MORE RIGID BULLET DESIGN IS FIRED IN THE LEADED BORE.
BE SURE TO REMOVE ALL CHAMBER AND BORE LEAD
ACCUMULATION AFTER EACH USE. DO NOT SHOOT
CARTRIDGES WITH JACKETED OR MONOLITHIC BULLETS
THROUGH A BARREL PREVIOUSLY FIRED WITH LEAD BULLETS
BEFORE THE BORE IS THOROUGHLY DELEADED.
CAUTION: STORE ALL CARTRIDGES OF DIFFERENT CALIBERS
IN COMPLETELY SEPARATE AND WELL-MARKED CONTAINERS.
NEVER STORE CARTRIDGES OF MIXED CALIBERS IN A
COMMON CONTAINER OR IN YOUR POCKETS.
FN has gone to great lengths to ensure the compatibility of the FN 503 with
a wide range of ammunition but it is recommended that you test your pistol
with any ammunition that you wish to carry for protection to ensure reliable
functioning.
If you have concerns about the compatibility of a particular ammunition
type or are experiencing malfunctions with a particular ammunition with
your FN pistol, contact FN customer service.