When is Red Dot not Red Dot?


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Catpop
March 29, 2013, 10:17 PM
I need one of the thread gurues to explain this one to me. I have a 1979 hardback Hornady reloading book thats gives a 38 spc 158 grain lswc Red Dot max load of 5.6 grains @ 1050 fps , yet the current Alliant soft cover list a max load of 3.1 grains of Red Dot @ 835 fps with15800 psi. What's the deal here?
Further using the Hornady book last night I loaded up what I felt were light to midrange loads only to now realize they may be seriously over loaded at 3.5 grains. What do you think?

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oneounceload
March 29, 2013, 10:24 PM
almost 40 years difference in materials and technology

rsrocket1
March 29, 2013, 10:27 PM
Your loads of 3.5g will be fine. 3.1g under a 158g bullet is a pretty soft load and so long as you have a modern gun, a little over 16k psi isn't going to harm it.

Old data was not as accurate as modern piezo transducers which can pick up much higher peaks than old equipment.

You might be at max with a pocket 38, but a mid range or larger frame 38 will easily handle it.

BTW, the Alliant web site says a Speer 158g LSWC takes 3.4g max Red Dot @ 793 fps.

exbrit49
March 29, 2013, 10:41 PM
I had posted about this same thing several months ago, I have been loading the 38 SPL with 4.6G of Red Dot under a 158G SWC for over35 years..
Yes its a pretty warm load and chrono's for me at around 1000, fps.
Having loaded and shot thousands of with no real pressure signs or issues, However, I use mine in my SW and DW .357s, These are built to handle the higher pressures.
I don't know what you are planning in using these in but if its an older 38 Spl, it may well be over pressure.
I don't want to preach but you should have really started at a lower charge and checked velocity and pressure signs.
I take all the reloading manuals as a guide only, and usually start pretty close to the start load and then move up in 2/10 grain increments until I reach an accurate load that shows no signs of over pressure. I always use a chrono and personally feel that you should always use one when working up new loads.
As I said earlier I use that 4.6G and love it, but it is too warm for an old 38!
One last point, I have noticed that all the modern manuals have really cut back on charge weights for most powders. Personally I think its a fear of litigation and they have cut way back in the loading tables. Some earlier responses said that they felt it was due to improvements in the powder, I don't buy that as the Red Dot from 30 years ago, chrono's the same as new powder I buy today.
As for your dilemma? if you are going to use it in a modern .357 it will be fine, but in an older 38, I would advise to pull them and use a modern load recommendation, then you can chrono and work up a load that you are comfortable with from a safety and recoil factor.

NCsmitty
March 29, 2013, 10:58 PM
Alliant's load site lists 3.4gr of Red Dot for 793fps with 158gr lswc, and the +p load is 3.8gr for 846fps. I would try some of the loads that you have loaded, and see how they shoot. If the cases do not stick, it should be safe. Starting loads are 10% less according to Alliant's site.

I'm well aware of the older manuals running hotter charges, and would only use them for a cross reference. Red Dot was reformulated a few years ago to burn cleaner, and is the main reason for the change in max loads. I use the different powder manufacturers/distributor data at their sites as my go to info. It is the most up to date data that you can find.

www.alliantpowder.com

www.hodgdon.com


NCsmitty

rfwobbly
March 29, 2013, 11:00 PM
Not only is there "drift" in the powder formulation over the decades due to new chemical manufacturing processes, but the methods of measuring chamber pressure have also changed drastically in that same time. If this weren't so, then we'd all be loading with the books from the 1940's.

Use the 1970 book only if you're loading 1970's powder. On the other hand, if you're loading powder you bought last week, then use last week's load data.

Catpop
March 30, 2013, 12:18 PM
Thanks to all for the quick response on this issue. I thought I really did start extremely low with the old data I had (30%+ below maximum), but as pointed out, I shouldn't use old data with new powder. I had planned to use these loads in a 1975 S & W m60 ss. Would this be safe? Again thanks to all!

rcmodel
March 30, 2013, 01:08 PM
I disagree that the Red Dot burn rate has changed over the years.
Because it hasn't.

If it had, there would be a lot of blown up shotguns, from shot-shell reloaders still using the same powder bushings they have used for 50 years.
And there isn't.

What has changed is, better pressure testing methods.
And Alliant & Speer have combined load data after Speer became the property of the same conglomerate, Alliant Techsystems Inc. in 2001.

As such, new Alliant data is only shown with Speer soft swaged lead bullets.
And the pressure & velocity they will stand is what determined the new lower max loads..

I don't know what bullet Hornady shows in your 1979 manual, but it might have been a real cast lead bullet that will take higher pressure & velocity.

rc

evan price
March 30, 2013, 05:03 PM
They started using piezo-electric pressure sensors instead of copper crushers. The piezo sensors showed spikes that were briefer than the copper crushers could react to. The electronic sensor can graph the pressure curve as a waveform in real time and show spikes that are only milliseconds wide. The copper crusher shows only that the copper was deformed, and a very short high spike won't get picked up reliably.
The spikes they saw were well above safe levels.
Then they reduced Red Dot data to more liability-friendly load levels.
I've got an old Speer #8 which shows some really aggressive loads for Red Dot in small frame guns.

Salmoneye
March 30, 2013, 05:39 PM
I disagree that the Red Dot burn rate has changed over the years.
Because it hasn't.

I agree fully...

I have canisters spanning 40+ years, and statistically it's the same stuff...

My oldest Red Dot (and it has more than 2# in it):

http://i49.tinypic.com/359heuc.jpg

1KPerDay
March 30, 2013, 06:07 PM
Ooo, Ooo, can I play? :D

http://i12.photobucket.com/albums/a206/1KPerDay/Guns/2d5e61b8.jpg

http://i12.photobucket.com/albums/a206/1KPerDay/Guns/17ea8c8a.jpg

http://i12.photobucket.com/albums/a206/1KPerDay/Guns/h4895%20canister/caec9665.jpg

IMO the reasons for the difference in data is simple: Lawyers. ;)

Steve C
March 30, 2013, 06:20 PM
Load data changes over time, sometimes up and sometimes down. Occasionally it can be explained by differing components and changes in measurement equipment. The early Hornady books listed data much hotter than the Sierra and Speer manuals of the same time. This has now changed somewhat with the current Hornady data being a bit lower than the current manuals from the other two.

The earliest "free" pamphlet I have from Hercules 1975 (now Alliant) listed 3.6grs of Red Dot behind a 158gr LRN as the max load. There was no +P rating in existence at that time so that was the equivalent of +P in those days. Current loads listed by Alliant and their corporate sister company Speer have increased the loads for Red Dot and Unique over the older Hercules data a bit.

Wise reloaders used the higher end early Hornady data for heavy frame .38's and .357 mags.

Jim Watson
March 30, 2013, 06:42 PM
I think 5.6 gr Red Dot and a 158 gr .38 Special is too much. You don't even see that much Unique listed for a 158 gr .38 and it is a much slower powder.

Jeff Cooper said 5 gr Red Dot and a 160 gr SWC would "get the .38 up off its knees" but was "contributing to the delinquency of handloaders."

Evan Price says:

"The piezo sensors showed spikes that were briefer than the copper crushers could react to. The electronic sensor can graph the pressure curve as a waveform in real time and show spikes that are only milliseconds wide. The copper crusher shows only that the copper was deformed, and a very short high spike won't get picked up reliably.

Which is true but I disagree with the part about:

"The spikes they saw were well above safe levels."

Those spikes, not apparent until the change from crusher to transducer, had been there all along, ever since any particular powder was introduced. They weren't blowing up guns then and it is hard to see how an oscilloscope trace makes them dangerous.

But I still think 5.6 gr Red Dot is too much.

Oh, yeah, an old Handloader's Digest pointed out that there were nine different grades of Red Dot, numbered 10 - 90.
Only Red Dot 30 was sold retail, the other eight burn rates limited to OEM ammo companies. Wonder if Hornady accidentally got some bulk Red Dot of a slower grade.

rsrocket1
March 30, 2013, 07:31 PM
1kperday,
Shame on you. That stuff should have been burned up decades ago. My powder might last me a year before I shoot it up. What do you think you have there, wine? :)

Match10
March 31, 2013, 01:23 AM
All the "____ Dot" powders were reformulated two years ago with slightly different results. My experience is they are not equivalent.

bluetopper
March 31, 2013, 02:37 AM
The newer powders may be less sooty and burn a little cleaner, but if the new Red Dot was not the same burn rate and energy as the old Red Dot they would call it something else. Powder companies know that old powder from 40 years ago is still out there and people are still looking up data for it.

I got into a heated argument a few months ago with some guy on a forum trying to tell me that the new 2400 was hotter than the old 2400 because charge weights were less now than in the 70's.:rolleyes:

Matt Dillon
March 31, 2013, 06:58 PM
Guys, I just picked up some Promo, for which Alliant says to use Red dot data. Anybody know if old data or the new Red dot data should be used?

bds
March 31, 2013, 07:21 PM
Matt Dillon, when I initially tested Promo using Red Dot load data by weight (as indicated by Alliant (http://www.alliantpowder.com/products/powder/promo.aspx)), I used current Alliant load data (http://www.alliantpowder.com/reloaders/Powder.aspx?powderid=4) with Lyman #49 and referenced 2004 Alliant load data (http://www.thehighroad.org/attachment.php?attachmentid=182147&stc=1&d=1364769070) for 9mm/40S&W/45ACP jacketed/plated/lead loads.

For 45ACP 200 gr SWC, I used current and 2004 load data along with Lyman #49 and settled with 4.0 gr - http://www.thehighroad.org/showthread.php?t=578444

For 9mm 125 gr RN, I used Lyman #49 and 2004 load data and settled with 3.8 - 4.0 gr - http://www.thehighroad.org/showthread.php?p=6480163#post6480163

For 40S&W 155/180 gr FMJ/TCFP, I used 2004 load data - http://www.thehighroad.org/showthread.php?p=6509911#post6509911

Matt Dillon
March 31, 2013, 09:17 PM
Thanks so very much for thes references!

Taroman
March 31, 2013, 09:50 PM
http://www.hverovhe.com/red_dot.jpg
Old or new, all mine runs the same:

Catpop
April 1, 2013, 01:16 AM
Up date: loaded up some 2.8 Red Dot and tried it first in my M60 Smith. Almost no recoil. Reminded me of a cap pistol Then I tried the 3.5 -again very little recoil and no signs of excessive pressure. So I increased it again and again finally stopping at 4.0 grains, still with no signs of excessive pressure. Makes me think the 1979 Hornady manual was correct after all. I'm not going to 5.6 grains as I am after an economical target load for my wife. But I wish I had a pressure tester just to see where this would go. Thanks to all who gave their valuable input this issue.

Drail
April 1, 2013, 01:57 AM
All those giant cans of Red Dot have got me drooling. I LOVE Red Dot. I would run 3.5 to 4.2 with 158 gr. Red Dot is a great light-medium load powder.

evan price
April 1, 2013, 03:07 AM
@jim watson... True a brief milliseconds wide spike would probably be ok and in fact a lot of guns were not blown up...butWe max pressure means do not exceed so the data had to be changed.

Steve C
April 2, 2013, 09:49 AM
So I increased it again and again finally stopping at 4.0 grains, still with no signs of excessive pressure.

If you ever see over pressure signs in a .38 spl you have gone way beyond the .357 mag level and over 2x the max level.

1KPerDay
April 2, 2013, 02:00 PM
1kperday,
Shame on you. That stuff should have been burned up decades ago. My powder might last me a year before I shoot it up. What do you think you have there, wine? :)
LOL I've burned up that can of red dot a year ago... and 2 more lbs of the newer stuff since. I'm working on the Herco now. :)

Catpop
April 2, 2013, 03:25 PM
Steve C, I'm confused, :confused: if the average reloader can't use indicators of high pressure in load development, how does he ever work up a load for a particular gun?

rbernie
April 2, 2013, 03:41 PM
if the average reloader can't use indicators of high pressure in load development, how does he ever work up a load for a particular gunPost-firing examination of brass/primers doesn't really provide a complete view of the actual event. For this reason, we work up from the starting load data towards the known published max (as tested by a facility with adequate instrumentation to show a complete pressure curve) and stop whenever abnormal signs appear prior to that point. This behavior helps ensure that we never get TOO out of bed with regard to safe pressures, but (as you've pointed out) our view of abnormal signs itself inadequate to ever really *know* what's going on.

Catpop
April 3, 2013, 03:11 PM
Rbernie, thanks for input. Is this pressure curve avaiable to me? If so from where? I'm not totally sold on the new reloading books vs. the old ones. Just me- have to see it. Thanks

plateshooter
April 5, 2013, 07:06 AM
I have loaded 4.7gr of Red Dot with 158 lead bullets in 38 special cases since the early 70s. I have shot many thousands of them in S&W K and L frame revolvers, and my Ruger Security Sixes. I never had any problems or indications of excessive pressure. A friend of mine using the same load shot one round in his S&W 637 Air Weight revolver and this was the result.

I load for the Air Weight revolvers that I have according to the current Alliant data of 3.4 gr for standard 38 spec loads using the 158 gr lead bullets. I don't use the 3.8gr +P loads that they list in these guns either.

This was the 1st shot of the day using a freshly cleaned gun. The bullet did exit the barrel. We couldn't find a hole in the target, or any pieces of the top strap or the cylinder. No one was injured and I was standing next to him when this happened. His comment was "that sounded different".



http://www.thehighroad.org/attachment.php?attachmentid=182345&stc=1&d=1365154292

rbernie
April 5, 2013, 08:52 AM
Rbernie, thanks for input. Is this pressure curve avaiable to me? You can ask the load testers, but it's not likely that they'll give you their data. You can always buy QuickLoad (http://www.neconos.com/details3.htm) if you want to see more than just load data results.

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