It is really surprising to me how different load data can be. I started out loading for the 44 mag some years ago now and I started as conservative as I could. My favorite load that was on the low end of the data on several sources turns out to be a full grain over the max in a reference I looked at recently. this is on a loading that is less than 10 grains. Firearms and twist and barrel length is not the culprit.
The data is for soft lead projectiles and other bullets, jacketed , in the same wt. range are not the difference either. I can understand small differences but not the difference between a low end conservative load and an over max. load. Nutzzzz!!!!

Load data for swaged bullets has been revised downward as these bullets do not generally shoot well in high pressure loading situations.

Other data has been revised downward as pressure testing equipment has matured.
There was an article on pressure testing equipment in Gun Digest thirty years ago which discussed the differences between the Copper Crusher and Piezo Transducer methods of measuring pressure.
The general consensus was there was so much variation in the Copper Crusher method of recording pressure as to bring all CUP data into question. Pressure testing equipment, data and technique has grown a lot in thirty years so it is not surprising to see some of the pressure data revised downward. If there is a good side to the story it is there has been a significant improvement in canister powders available to the handloader and this has allowed us to improve the performance of our handloads in some instances without raising pressures above a safe level.

Certain cartridges such as the 44 Magnum that we started out for in the 1960’s are now loaded with completely different powders. For top loads our old standbys such as Alliant (Hercules) 2400 are not obsolete, having been effectively replaced by Hodgdon 110 and Winchesterlace 296. H110 and W296 are in turn in the process of being replaced by Hodgdon’s Lil’ Gun and other powders.
The Remington SAUM and Winchester WSM ans WSSM cartridges could not have been developed without the new powders.


These are the best of times for the home hobbyist and the next thirty years are going to be amazing. I’m 56 and have listened to my father describe how to melt kitchen matches to reload primers for use with black powder cartridges – I have no concept of how tough times were in the 1930’s.

Today I describe using Lyman 310 tools, hand seizers and Lee hammer-powered handloading tools to young men who started reloading on a progressive press and they lock at me like I am dinosaur! If I like them I break out the Lyman Tru-Line Jr. press and my Dads old Pacific tool.

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slim

I do feel that it is useful to run loads over a chronograph, as a sanity check to see whether the velocities are expected. If so it's much less of a concern than whether the load matches every manual that I own....

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MikeG

This Green Dot could sure fit in that swagged shift category. The speer cat that is so low is ed.12 from 95 I think. The Hodgedon ed is from the same time and it shows the same as the loadings that came with my 1st Lee Loader. I do not think I have ever cronyed the load so that has to go on my list of things to do on my next range trip.