to the 1932 National Firearms act.
If it is doing it now, then it a bad dis-c0nnector.
Second, confirm the SN on the barrel is the same as on the right reciever front edge, IF NOT the have the headspace checked as the pre-855,000 Sn receiver and barrels were specifically mated and headspaced.
After 1963 (post 855,000 SN) barrels were interchangable.
Goggle diamond gunsmithng , the owner is retired cheif engineer of the Ithaca NY, Ithaca gun and specilizes in the 37.
Recommend two other websites:
www.16ga.com
www.shotgunworld.com good ithaca forum here.
Enjoy.