Normally Yes; It sometimes possible to hold the bbls hard forward & get them to catch & cock the hammers with forend off. This pin was very precisely located so that just the slightest movement to the rear allowed it to slip past the hook for disassembly so normally it will not catch with forend off. If it is not catching with forend on then pin may be bent & need replacement.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra