I've worked with those 135's before and in several different firearms. What I ended up doing was contacting Speer to get the OAL they tested it at, and then using that OAL as a base line to work off of. I have that information some where in my reloading data and will try to locate it for you. But in the mean time I would start at 1.125" and if that clears the lands, fit the magazime, you should be fine.
FYI, increasing the crimp on a rimless cartridges only decreases neck tension, so do not make that mistake. Maximum neck tension on these type cartridges is achieved by not bellng the case mouth, and then by deleting the crimp. I have been using this method to seat all jacketed bullets and Gold Dots in rimless cartridges for many years, with excellent results. Just give the inside mouths a nice even chamfer to eiminate shaving.
GS