working up to a max load

[modwerdna]

What is the first sign you use to determine you have reached an over-max load on a wildcat ?

Primers can flatten sometimes on normal loads like 30-06.

Cases can stick if the chamber is rough.

Primer pocket blow out? that seems like it might be way too far down the road.

I have worked up a few not listed loads looking for problems on the cases, but have never really liked the concept.

 

[jim147]

I would start with a micrometer and a chronograph.
Case head exspansion and fps tell a lot more than the primer.

 

[USSR]

Primers can flatten sometimes on normal loads like 30-06.

Yep, primers will lie. Knowing what velocity is reasonable to expect, and determining what velocity you are getting over your chronograph should be your starting point. Then, the small circular "smudge" mark on the cartridge base caused by brass flow into the ejector hole, tells you you are beyond where you want to be. Sticky bolt lift is another sign. Even if I reach a velocity that I feel is the best to be expected from a particular load without high pressure signs on the brass, I stop there. On the other hand, your brass may exhibit pressure signs well before you reach the velocity that you expected.

Don