PN 2002: M14 Adaptor, Castle Nut Type
Machined from fatigue proof steel bar stock. Includes wire EDM internal male splines and rectangular hole for the castle nut. Threaded 5/8″x24, with .735″ length of thread, a common size that fits most other accessories.
The dove tail deck will fit any USGI type front sight, including:
P/N 2055 SEI/USGI standard front sight
P/N 2004 NM .062
P/N 2018 Tritium Bar Stripe
P/N 2019 Tritium Dot
If you are using this with an 18 inch barrel:
18″ barrels will shoot higher than 22″ barrels. To compensate, SEI recommends P/N 2012 GLFS-D-18, or P/N 2013 GLFS-D-18 Gas Lock that is at the correct height, mated to a standard front sight such as the ones mentioned above. Springfield Armory uses a taller front sight like the Springfield Scout.