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curioushooter
12-25-2018, 02:18 PM
I started reloading in 2008, so all the powder and all the reloading manuals (many downloaded) have been from that era or later. Over the last two years two different discoveries I've made that made me realize how certain priorities people and companies may have in reloading can end up being quite reckless.

The first bell went off when studying load data for the 357 Herrett cartridge, which I believe had all of its testing done in the late seventies or early eighties long before the transducer type pressure testing equipment was in use. Old listings for 357 Herrett have 34 grains of A1680 driving 200 grain bullets at near 35 Remington velocities. Newer listings have backed that off considerably (into the high twenties) but none of them (like Hornady's) contain pressure data (that they are telling us at least). This makes me think they just backed it off because they figured it would go easier on everybody and reign in the tendency of Contender shooters to hot-rod everything. It was around this time I bought a chronograph (mainly because of the Contender), which was a real eye opener, and makes me mistrust data provided by powder manufacturers (especially Hodgdon).

The second more alarming bell went off in studying cast bullet loads for 357 Magnum. The reloading manual that has always been my Go-to with 357 magnum (which I mostly shot jacketed bullets out of until the last couple of years) was Lee's 2nd Edition. In fact, I don't think I ever looked at 357 data from any other source besides Vitavouri's 4th (which uses CIP standards, which are quite hot). Then my father-in-law lent me his 1992 published 47th edition of the Lyman reloading handbook, which was an eye-opener, because it uses reasonable barrel lengths (4" and a vented test barrel I assumes is meant to replicate the effects of the cylinder gap). This was perhaps one of the last manuals published before the SAMMI downgrade of the 357 Magnum. I also uses the old copper crusher type test. Some of the max loads in the Lyman manual are near starting loads in the Lee. This alarmed me set off a search where I then studied all the data I could find. What a surprise.

Basically 357 Magnum was reduced considerably in 1995. With today's loads, one is hard pressed to get 158 grainer going 1400 out of normal revolver barrel. Alliant 300-MP might be able to do it. It is, of course, a very dense and slower version of Win296/H110, which in my opinion, are already too slow and just blow powder out the muzzle. I have not tried 300MP, and I have hopes that it was designed to actually get lit and burn efficiently at the lower 35,000 PSI limit (because it is a new powder). I think I will give it a try next time I am in the powder store.

I have never been one to hot rod in revolvers (or really any handgun besides a Contender), but I was really surprised to learn that classic 357 "mid-range" loads like the 13.5 grains of 2400 with a 358429 are overmax by today's standards. Loads like 14 grains of 2400 with with 358477 which are bandied about routinely are over pressure. In any case, what I find reckless is Hodgdon's data. They are still listing, for example, Win296 on their website using the old CUP units running up into the 40s, so this data is probably pre-'95. They also list it with 10" barrel (which is presumably sealed, not with a vent or gap). I know why, too. It's because of the advertising qualities of that old data compared to today's. Why would anyone buy a bottle of 2400 when 296 is way faster? The thing is that it has been 20+ years now since the downgrade and there are many 357 revolvers floating around there that have been manufactured to the lower power standard presumably. What comes to my mind are the J-mag frame S&Ws. But there may be other examples in other cartridges, like the 6.5x55.

I am not someone who places much faith in the shooter's ability to determine pressure from incidental signs like primer condition or case web expansion (which I think is a far better and only requires a cheap micrometer). The way I look at it, if you are seeing goofy stuff with primers you are long past over pressure (especially with low pressure cartridges like 45 ACP, 44 or 38 Special). I suspect that if someday an affordable way to measure pressure is developed, that it will be as illuminating as the $100 chronograph was. We are still half-blind when it comes ballistics (external we have, internal we're in the dark). Given this, try to get your hands on as much data as you and can compare grain weights of the same powder before ever selecting a starting load. Get manuals from both BULLET and POWDER companies, and I would say study the Vitavouri for some euro perspective.

JBinMN
12-25-2018, 02:28 PM
Interesting & seems like some pretty good points to ponder on!

I have noticed a lot of changes from my old manuals to the newer ones as well & that has been discussed here before more than once, from my reading of the CB.GL archives.

IMO, it is good that someone brings up this sort of thing on occasion, to see what insights others have in regard to these changes. As more member join & participate here, it makes the info available increase to everyones benefit much of the time. The more we know, the better & more informed decisions we can make in our handloading, IMO.

I am looking forward to reading more when folks add in their 2 cents.
:)

Thanks for sharing your thoughts!
:)

GARD72977
12-25-2018, 02:33 PM
Primers are really not a good indicator of pressure. If you were using a known lot of primers that might work but too many variables. I test a lot of ammo way under SAMMI but the primers look horrible.

GARD72977
12-25-2018, 02:36 PM
CUP test seem to be more consistent than PIEZO gauges. Not sure what that means. Im leaning toward CUP is not as accurrate.

country gent
12-25-2018, 02:54 PM
One other thing is with modern manufacturing and technologies powders (even the old stand bys like bullseye 2400 unique IMR4895) have slightly changed, Thus making changes in data needed. Blue dot is a good example of this in modern manuals for 41 mag its greatly reduced or not mentioned at all, It was the go to powder for years in 41 mag. The older manuals were even more "generous" on data given.

In the wildcats ( 30 herret, 357 herret, 6.5 X 284) pressure numbers may not be given due to all the small variances in chambers and throats. Along with the differences in brass it may be formed from.

A real eye opener on this is to pick up one of the one caliber manuals for a given caliber and look it over. These contain data from powder companies, reloading equipment companies, bullet makers., basically most of the available data in that caliber under one cover. This shows the differences quickly.

Hick
12-25-2018, 08:09 PM
I think the message here is that, if you are dealing with something new, it is not a good idea to rely on one manual. Compare. Compile all the data from every reloading manual you can find for the caliber and bullet you want and compare the starting and max loads. The OP is dead on--I have done this a few times and, if you compare enough, you will see the inconsistencies and can safely figure out where to start.

tazman
12-25-2018, 08:22 PM
Another reason to have data from more than just the powder manufacturers is the difference in bullets regarding pressure. Different manufacturers use different alloys in their jackets. Different length drive bands and other differences add up to some significant differences in load data.
For instance, check the difference between load data for the Hornady XTP and the Hornady HAP. Big differences between two same weight bullets from the same manufacturer.
I used to ignore that kind of thing. No longer.