In the Nosler manual there is an extra caution when using Fail Safe and Partition Gold bullets to be sure to work up your load very slowly. More caution than normal. Does anybody know why this is? Why is there more danger, if any?

Also in the Winchester manual the Fail Safe is loaded less than a similar weight bullet in the same caliber.

Those rounds are harder and have a longer bearing surface, compared to other Nosler bullets in the same caliber and weight.

paraphrased from manual--"due to internal construction differences"

I would guess that it's due to the steel cups they put in just aft of the partition. It's probably harder to try to squash those cups (if they do) than it is to squash just plain lead. Those are the only 2 bullets they have that on.

irwin

Irwin hit it right on the head. Depending on the depth of of the rifles land and grooves and how fast it tapers from the chamber throat to the end of the muzzle. You would want to build the loads up slowly, inspect cases or watch for other high presure signs like a stuck bolt. ect.

Those bullets are built like a brick shit house. Strong!

All the answers above are correct. You will love the failsae. I have loading some for my friend. Aaron has 6 kills with six shots. no moved further than 10 yards. One even "ate" dirt as it just collasped. These are not the top barn burner loads either. They were about mid level in the manual. The bearing surface being longer does hav an effect on pressure, so start safe and work up. Good Luck.

Hcliff

The partition gold has a thicker jacket than the std partition or the ballistic tip. I found out (the hard way) that the max load for my .30-06 super-improved with 180 grainers was 2.0 grains lower with the gold than the ballistic tip. The force to obturate the thicker jacket and steel cup is higher than with the thinner jacketed bullet, thus the pressure is higher. I think that the CT failsafe max load is probably even lower than the gold. The old caveat "when changing any component, drop 5% or more, and work back up." I took a short cut and got burned. Lucky for me, the Ruger #1 is one hell of a strong action. All that happened was the primer fell out of the primer pocker, but this means well over 70 kpsi, which is not too safe.