Thread: Testing a conventional approach to load development

Originally Posted by Sidetrack

Ignore this, can’t seem to edit. GPM raised the 260 load data issue and you’re gone part way to explaining your thinking. The chamber differences still bug me but if they’re still within tolerances can we assume we’re still ok? I ask this as I was getting bolt lift issues at the bottom end of powder charge when loading for my 270. It was my first handload so I was being conservative but it stuck with me, hence the questions.

Two 270s get loaded for from my bench.one is near top of book load,the other sits between start and midpoint. No way would I load for the second rifle and hotter. Possible a short throat/ jump till pill hits rifling is the difference. If you look at Weatherby rifles of old( not sure of new ones) they had quite a spacewalk for projectiles which allowed a longer burn and higher charge perhaps? The new hypersonic shotgun rounds work on similar principle. By allowing payload to start moving forward it sort of increases the volume of the case....hopefully that makes sense??? It's why seating deep increases pressure,smaller volume.