Note that the 2 3/4" hulls, even with the proper loads should be used in the short chamber "ONLY" if it has the fold crimp. It should not be roll crimped unless shortened. There is a distinct possibility if the longer shell with a roll crimp is used the shell will fit up in the forcing cone "Prior to Firing" & put extra resistance to the crimp opening with a possible increase of pressure. All the tests I am aware of sanctioning the use of hulls longer than the chamer were done with fold crimp shells, whose loaded length was approximately equal to the loaded length of the shorter roll crimped shell for which the gun was chambered.
