changes over the years IMR 4895? 30-30 max loads...

[SpeedyR]

was digging thru some older ammo (30-30) that my dad made years ago. Mostly 130 and 150gr FN speer bullets. I went to check the loads in my current load books and found that they were over the max loads listed in the books (Hodgdon 2012 magazine, and IMR booklet). That was very unusual to me as he always did more low to middle of the road loadings, so I got out a few of the older manuals, mainly Hornady Handbook Vol II from 1973 that would have been his main source for loading info.

Basically that manual has the min load for 30-30 with 4895 at 30.4 gr and max load at 36.1gr (2400fps). Dads load (35.0gr) would clock in around 2300fps according to the manual.

The current max load of 33.5 gr is around 2200fps.

so have the max pressure levels gone down over the years? powder gotten more efficient over the years (same brand and model), or have they just dropped their "max loads" to ensure no one blows up their rifles? I'm guessing the latter as the velocity is the same they just stop at the 33.5 grains and don't give you any higher velocity numbers.

I don't care too much about the velocity, I just want to make sure that I am not loading +p loads into the 92 and 94. I know he shot a fair amount of the loads, because some of the boxes are half empty, but just curious to hear what you guys think.... I don't really want to pull all of them apart, as I have about 100 of them around, but also don't want to have issues with the ammo/rifle.

 

[Chuckdog]

They have improved the methods used for measuring pressure.

Short spikes that were previously undetected by the older methods show momentary pressures
that have caused many to be revised.

 

[loadnplenty]

I have some older reloading manuals that I have compared to new manuals and have found the listed max loads have came down. I read an article once that best summed it up I guess, and it stated new powders are more refined and thus getting better velocity with less powder. Makes sense to me!

If you are worried about the preasure, I would pull the bullets and dispose of the powder. JMO

 

[Petro_58]

They have improved the methods used for measuring pressure.

Short spikes that were previously undetected by the older methods show momentary pressures
that have caused many to be revised.

This and the Legal Teams for the Powder Companies have helped drop some of the Max charges from the Older manuals, and revisions due to better quality control proceedures in manufacturing of powders.