Thread: Signs of pressure in a 6.4x47

Originally Posted by zimmer

I was mindful however b4 I started of the very strong 6.5x47L SR primer case's ability to hide to a certain extent the onset of high pressure (within reason) also the Barnard action I have found doesn’t always present sticky bolt lift as early as some other actions. Plus that action has no ejector hole for brass flow. Have tried the head expansion measurements in the past but that is not always conclusive – I had an article debunking head measurements as the finite method but can no longer find it.

Cases have had 4 loads now and no issues detected with them to date.

The 130gr Bergers shot 5 shot 100yd groups of =<0.2 on good days and =<0.4 on bad (read me) days.

The equal most accurate rifle I own.

Thanks Zimmer, the above closely matches my situation and experience with this case. Bloody accurate but somewhat problematic for me as I'd like to explore the full spread of available velocities before picking my final load, meaning development up to some level that I remain uncertain about. QuickLoad points to a slow batch of 2209/H4350. It would be more reassuring if the program gave a better match as I'm already at 42gr behind a 140grVLD. I'm thinking I'll dig out the Pressure Trace and stick on a strain gauge - see what that has to say.