Good thread. Several good tips. I might have to buy a handful of those Sinclair Chamber Length Gauges.
I started reloading (in the '70's) when most of us relied on pressure indicators like flattened primers and ejector marks on the case head. It scares me to think of some of the loads I used to shoot in my 308 and 25-06 that were wayyyy too hot. The chronograph is probably the best pressure indicator available to the majority of us. I like primer pockets to remain tight after multiple loadings.
Yes, finding the chamber length can save a lot of time and cost. I'll bet most folks trimming .223 for their own rifles would never need to trim at all.
