I keep seeing remarks about someones pe64 70. Back in the late 40s, there was a test done to determine which actions were strongest, and they actually tried to blow the guns up. The Mauser 98, springfields, 17 enfield, model 70 and the then new 712 were tested. The model 70 was strong enough that (06) case FULL of proof powder with a 180 grain bullet was loaded. Nothing, so additional bullets were pushed down the barrel on top of the load..I believe it got to 2 or 3 additional 180gr bullets on top of the loaded round, before the gun blew the extractor and etc..and I believe, bulged the action. Gen Hatcher ran the tests..the 721 went through the same test, but took another 5 or 6 180gr bullets down the barrel on top of the proof load, and never did blow up. DID lock the action up, so a mallet and 2x4 were needed to get it open. I don't believe it bulged the action even.. SO, the model 70 and 700, are plenty strong, and the model 77, might be even stronger, not having any stress in the making (its a poured action)..
With my load of 60grs of 4350 we got no pressure problems. Note the pressure shown on the Hodgdon site was 47K which is real low.