old data vs. new nata

[Boolseye]

Looking through my old '73 Hornady manual I'm struck by the wild disparity between the .38 special data contained therein and the data you'll find nowadays. Top load for a 158 in the old manual is 5.7 grains of BE, 10.6 grains of 2400. You'll see maxes for BE at around 3.8 these days, maybe 8 gr. 2400. Lawyers, guns and money, I suppose. Still, the anemic data that passes for +P in modern manuals doesn't even begin to challenge my S&W. Any other similar observations?

[Scharfschuetze]

All the older manuals used data developed by technicians who may or may not have used the older copper or lead crusher methods of determining chamber pressure. Now most testing is done with the Pizzo Electric or strain gauge methods. These produce much more accurate data and have shown some of the older pressure measurements to be false and at times dangerous. SAAMI is the authority on dimensions, pressures and other related minutia so the new data generally falls within their guidelines.

In addition, as you surmise, in this litigious society with too many lawyers, litigation is always in the mind of anyone who produces or publishes absolutely anything including firearms info.

While your S&W (and mine) does not seem to be challenged, there are many older firearms out their that are challenged by higher pressures.

[shredder]

When modern pressure lab testing started, lots of old loads revealed dangerous pressure levels. Maybe not "sudden destruction" level of dangerous but beyond the long term working pressure limits of the steel. This is likely one of those cases.

[jsn]

It's a good idea to get load data that corresponds to the age of the powder if you ask me. Powders have also changed manufacturers over the years as well.

At this stage I get several sources of data and "triangulate" from there.

[salpal48]

Most if Not all of the new Data. has all disclaimers. . . . You can Contribute it To new processes. , New Technology. and all That new . stuff. The Only difference In my Opinion. are Lawyers. Todays data Is all Lawyered up. I only use Old data. I have a good collection of Older manuals. some dating to 1930.
Where the powder is still available, I have tried them without any difficulty.

[JRD]

I met Ken Ramage about 10 or more years ago. He edited the old Lyman Cast Bullet Handbook. He specifically warned me about the early spiral bound editions because they contained "submitted data". As in "submitted" by reloaders to Lyman and published without being pressure tested.
The advances in pressure testing equipment have indeed revealed that old loads generated pressures in excess of the SAAMI limits.
As stated, they won't necessarily blow your gun up in one shot, but they will accelerate wear. I strongly recommend to stick to the more conservative, pressure tested loads. Your guns will thank you and give you a longer service life in return.

[knifemaker]

Don't fool yourself by believing it was just lawyers that caused powder companies to lower the amount of powder used in reloading data. With newer and better testing equipment, SAAMI found that many max loads in the manuals were on the border of being dangerous in some guns. The older system used CUPS for giving pressure limits and the newer system is rated by PSI and is more accurate. SAAMI even lowered the pressure limits for some calibers, some being the 44 mag, 38 special, and 357 mag. because the max in older manuals was treading into dangerous territory.
So if your reloading manual is using CUPS for pressure levels, be careful and check other sources for a safe and sane load.

[Boolseye]

Caution is always wise in this field. Thanks guys.
To any newer reloaders-don't hotrod your guns. Stick to published data.

[runfiverun]

heck in the old day's canister lots of powder wasn't all that great.
you could buy 4895 and get nearly 3031 one time and nearly 4064 the next.
not working a load up every time you got powder could be a disaster.
of course when you add in those guy's that learned to 'just work up a load until the bolt got real sticky then back it off a grain' factored in.
then add in a switch to a fast lot of the same powder and use the previous slow lot data and you can see what could happen.

[Kosh75287]

Darned shame, though. I actually did work up to 8.0/Unique/158LSWC (from a 1971 Lyman loading manual) in my Ruger Police Service Six, and it shot REALLY well. IF I was over-pressure, neither the cases, primers, nor the revolver seemed to notice. I dropped the charge to 7.6/Unique when I saw newer data. It was just never the same, though.

[dragon813gt]

Don't fool yourself by believing it was just lawyers that caused powder companies to lower the amount of powder used in reloading data. With newer and better testing equipment, SAAMI found that many max loads in the manuals were on the border of being dangerous in some guns. The older system used CUPS for giving pressure limits and the newer system is rated by PSI and is more accurate. SAAMI even lowered the pressure limits for some calibers, some being the 44 mag, 38 special, and 357 mag. because the max in older manuals was treading into dangerous territory.
So if your reloading manual is using CUPS for pressure levels, be careful and check other sources for a safe and sane load.

This is the explanation. They're able see the pressure curve in real time. Couldn't do this w/ the copper crusher method. Some Blue Dot loads went away because of how much it spiked pressure. It's modern advances in measuring equipment, more than lawyers, that have been reducing loads.

[Fernando]

guy's that learned to 'just work up a load until the bolt got real sticky then back it off a grain' factored in.

That brings a smile to my face - fond memories.

[jeepyj]

Though I'm not the OP this post contains very valuable information at least for me to learn from. Debunks the my thoughts the of why the data has changed through the years. - Jeepyj

[rintinglen]

Another factor in the 38 load reductions was the tendency to include 38-44 loads as part and parcel of the 38 Special Tables and not separate. That continued over into the days when the 38 plus P came to be and often the top load was +p, with little or no explanation that such was the case.
the 357 and 44 Magnum reductions were strictly Lawyer-induced by Smith and Wesson because they had made guns that were breaking--Model 19s and M-29s that couldn't handle the pressures that the folks up in Connecticut built their's to handle. Now a 357 magnum SAAMI load is maxed out lower than the the 38 Super. An N-frame S&W Model 28 can take a licking and keep on ticking.

[Oyeboten]

At least Black Powder loadings have not changed!

[Texas by God]

RunFiveRun- remember Bob Forker's "shoe method"? If you have to use your shoe to open the bolt-you've overdone the charge weight! Best, Thomas.

[atr]

I am still successfully using my reload manuals from the 1960's,,,speer, lyman and sierra. I have loaded maximum loads from these manuals without incident. When I compare the information in the old manuals with that published in the newer ones the difference does not seem to great.
I think the old manuals are still a good source of load information, but when pushing to maximum loads listed do so incrementally and pay attention to things liked fired case extraction, blown-out or flattened primers, etc.
use common sense...something that is sadly lacking in our modern culture