As I mentioned in a recent post, I came across a can of 60’s vintage HS-5 powder. Interested in testing odd-ball powder for no other reason than because I can, I put together 5 each of the following sample loads from ancient tombs of magic I have on hand. I also threw in a couple loads using 452-AA from a round can I also picked up at the show (probably 70-80’s production).
• Initial load data was derived from Speer #8, #10, #11 & Hornady 3rd ed.
• Bullets were wheel weights cast with a Saeco #294-382. Rated as 158gr samples weighed between 161 & 163 grains, air cooled, unsized and coated with alox. Due to the slight extra weight I approached 158gr max data with caution in mind.
• Primers were Winchester WSP & WSPMag
• Cases were Nickle Speer (357) & R-P (38)
• Crimp was medium taper (not rolled) and was positioned at the far edge of crimp groove.
• OAL was nominal 1.46” for 38 and 1.59” for 357 Mag.
Speer used 6” barrels testing both 38 & 357, so I used a 6” for testing 357 loads. It was interesting to note that not only did they reduce the published loads in #10 but they also switched the test gun to a Ruger. Knowing that Speer #8 manual is notorious for hot loads (some may say over pressure) and despite their test gun being a M-14, I was a bit leery of using my 6” K frame for testing these loads. I was left with only one choice I felt comfortable testing the unknown with… a 5” Heavy Duty. Hopefully the 1” of velocity loss will be minimal.
Note: In the following charts all data use HS-5 and 160 LSWC unless noted otherwise.
Speer #8 & #10 have big differences in their start & Max loads (especially for 357 Mag) as shown in the next table. #8 loads gain 19fps per 1/10 grain where #10 only gains 15.3 fps. In particular, notice the 57 fps velocity difference for the 38 Spl. 6.0gr load. Part of the loss could be the extra jump from using 38 cases in 357 chambers and the rest just because it’s a different gun. For my testing I started at 5.5 gr and stopped at 6.0 to look at my data before trying anything stronger.
There is a bigger difference in the 357 loads and gun tolerances probably don’t account for all of it.
Cal________Book______Start____fps____Max____fps____Note
38 Spl____Speer #8_____6.0____1007____6.5____1102___6” SW M-14
38 Spl____Speer #10____5.4____858_____6.0____950____6” Ruger Security-6
357 Mag__Speer #8_____7.5____1136____8.5____1251___6” SW M-27
357 Mag__Speer #10____6.4____944_____6.9____1017___6” Ruger Security-6
Just to be able to compare data with the 38 loads, I started at 6.0 gr and went in ½ gr inc. up to 7.5 gr. For interest sake, I made 4 loads of 6.0 gr HS-5 for comparison of 38 vs 357 case and std vs magnum primer (most Speer loads specify a magnum primer with HS-5 but Hornady and Lyman manuals don’t). I then estimated the expected velocity using the above Speer #8 data and my 5” barrel and show it next to my recorded velocities taken 10' from muzzle.
Cal_______Bullet___Powder___Gr____Est.fps__My.fps__SD__ES___Note
38 Spl____160 LFP__HS-5____6.0____875_____887____18___42___WSP
38 Spl____160 LFP__HS-5____6.0____924_____914____11___28___WSPMag
357 Mag__160 LFP__HS-5____6.0____816_____817____23___56___WSP
357 Mag__160 LFP__HS-5____6.0____841_____837____12___29___WSPMag
Notice that the 357 Mag loads are significantly slower than those from a 38 Spl. This is likely due to the reduced powder charge in a larger 357 case, Despite 1” longer bbl, could it be that the smaller charge of powder is not burning optimally? It doesn’t seem to be getting erratic yet.
Coming up with estimates of the 357 load was a bit trickier and more guesstimate than scientific prediction. The lowest Speer #10 357 start charge is 6.4gr so I was in unknown territory with 6.0. Speer #10 loads get 14.6 fps per tenth grain so estimating backwards from my known 6.5gr. 914 fps load, I est. 841 fps for the 6.0 load w/ magnum primers and then subtracted 25 fps for the standard primer load, (since that is typical of my other results). Had I used the Speer data for 6.4gr, I would have arrived at 885 fps. As it turned out, my estimate was right on the money out of my gun.
The rest of the loads turned out as follows. Notice that as is the case above, Magnum primers produce better SD & ES as well as tighter shot groups.
Cal_______Bullet__Powder___Gr____Est.fps__My.fps__SD__ES___Note
38 Spl___160 LFP__HS-5____5.5____823_____829____18___39___WSP
38 Spl___160 LFP__HS-5____5.5____850_____852_____5___12___WSPM
38 Spl___160 LFP__HS-5____5.7____847_____838____19___45___WSP
38 Spl___160 LFP__HS-5____5.7____878_____880____18___43___WSPM
357 Mag_160 LFP__HS-5____6.5____959_____914____13___32___WSPM
357 Mag_160 LFP__HS-5____7.0____1032____985____20___55___WSPM
357 Mag_160 LFP__HS-5____7.5____1105____1036___18___43___WSPM
The can of W-452 was a bit easier to compare since there were only 2 loads each, a start & a max. I was very pleased to see that my results closely matched the book, even using a shorter bbl for the 38.
Cal____Bullet__Powder___Gr___Est.fps__My.fps__SD_ES
38____160 LFP W452____3.6____763____781___20___51
38____160 LFP W452____4.0____842____841___10___24
357___160 LFP W452____5.0____960____949___13___37
357___160 LFP W452____5.4___1004___1009___12___29
This turned out to be a fun day out at my secret shooting spot in the desert.
None of the loads produced sticky extraction or noticeably flat primers
so I think there will soon be a bunch of new loads put back for a rainy day. 
These days I just love finding $7 a can powder, especially when it’s full.
• Initial load data was derived from Speer #8, #10, #11 & Hornady 3rd ed.
• Bullets were wheel weights cast with a Saeco #294-382. Rated as 158gr samples weighed between 161 & 163 grains, air cooled, unsized and coated with alox. Due to the slight extra weight I approached 158gr max data with caution in mind.
• Primers were Winchester WSP & WSPMag
• Cases were Nickle Speer (357) & R-P (38)
• Crimp was medium taper (not rolled) and was positioned at the far edge of crimp groove.
• OAL was nominal 1.46” for 38 and 1.59” for 357 Mag.
Speer used 6” barrels testing both 38 & 357, so I used a 6” for testing 357 loads. It was interesting to note that not only did they reduce the published loads in #10 but they also switched the test gun to a Ruger. Knowing that Speer #8 manual is notorious for hot loads (some may say over pressure) and despite their test gun being a M-14, I was a bit leery of using my 6” K frame for testing these loads. I was left with only one choice I felt comfortable testing the unknown with… a 5” Heavy Duty. Hopefully the 1” of velocity loss will be minimal.
Note: In the following charts all data use HS-5 and 160 LSWC unless noted otherwise.
Speer #8 & #10 have big differences in their start & Max loads (especially for 357 Mag) as shown in the next table. #8 loads gain 19fps per 1/10 grain where #10 only gains 15.3 fps. In particular, notice the 57 fps velocity difference for the 38 Spl. 6.0gr load. Part of the loss could be the extra jump from using 38 cases in 357 chambers and the rest just because it’s a different gun. For my testing I started at 5.5 gr and stopped at 6.0 to look at my data before trying anything stronger.
There is a bigger difference in the 357 loads and gun tolerances probably don’t account for all of it.
Cal________Book______Start____fps____Max____fps____Note
38 Spl____Speer #8_____6.0____1007____6.5____1102___6” SW M-14
38 Spl____Speer #10____5.4____858_____6.0____950____6” Ruger Security-6
357 Mag__Speer #8_____7.5____1136____8.5____1251___6” SW M-27
357 Mag__Speer #10____6.4____944_____6.9____1017___6” Ruger Security-6
Just to be able to compare data with the 38 loads, I started at 6.0 gr and went in ½ gr inc. up to 7.5 gr. For interest sake, I made 4 loads of 6.0 gr HS-5 for comparison of 38 vs 357 case and std vs magnum primer (most Speer loads specify a magnum primer with HS-5 but Hornady and Lyman manuals don’t). I then estimated the expected velocity using the above Speer #8 data and my 5” barrel and show it next to my recorded velocities taken 10' from muzzle.
Cal_______Bullet___Powder___Gr____Est.fps__My.fps__SD__ES___Note
38 Spl____160 LFP__HS-5____6.0____875_____887____18___42___WSP
38 Spl____160 LFP__HS-5____6.0____924_____914____11___28___WSPMag
357 Mag__160 LFP__HS-5____6.0____816_____817____23___56___WSP
357 Mag__160 LFP__HS-5____6.0____841_____837____12___29___WSPMag
Notice that the 357 Mag loads are significantly slower than those from a 38 Spl. This is likely due to the reduced powder charge in a larger 357 case, Despite 1” longer bbl, could it be that the smaller charge of powder is not burning optimally? It doesn’t seem to be getting erratic yet.
Coming up with estimates of the 357 load was a bit trickier and more guesstimate than scientific prediction. The lowest Speer #10 357 start charge is 6.4gr so I was in unknown territory with 6.0. Speer #10 loads get 14.6 fps per tenth grain so estimating backwards from my known 6.5gr. 914 fps load, I est. 841 fps for the 6.0 load w/ magnum primers and then subtracted 25 fps for the standard primer load, (since that is typical of my other results). Had I used the Speer data for 6.4gr, I would have arrived at 885 fps. As it turned out, my estimate was right on the money out of my gun.
The rest of the loads turned out as follows. Notice that as is the case above, Magnum primers produce better SD & ES as well as tighter shot groups.
Cal_______Bullet__Powder___Gr____Est.fps__My.fps__SD__ES___Note
38 Spl___160 LFP__HS-5____5.5____823_____829____18___39___WSP
38 Spl___160 LFP__HS-5____5.5____850_____852_____5___12___WSPM
38 Spl___160 LFP__HS-5____5.7____847_____838____19___45___WSP
38 Spl___160 LFP__HS-5____5.7____878_____880____18___43___WSPM
357 Mag_160 LFP__HS-5____6.5____959_____914____13___32___WSPM
357 Mag_160 LFP__HS-5____7.0____1032____985____20___55___WSPM
357 Mag_160 LFP__HS-5____7.5____1105____1036___18___43___WSPM
The can of W-452 was a bit easier to compare since there were only 2 loads each, a start & a max. I was very pleased to see that my results closely matched the book, even using a shorter bbl for the 38.
Cal____Bullet__Powder___Gr___Est.fps__My.fps__SD_ES
38____160 LFP W452____3.6____763____781___20___51
38____160 LFP W452____4.0____842____841___10___24
357___160 LFP W452____5.0____960____949___13___37
357___160 LFP W452____5.4___1004___1009___12___29
This turned out to be a fun day out at my secret shooting spot in the desert.
None of the loads produced sticky extraction or noticeably flat primers so I think there will soon be a bunch of new loads put back for a rainy day. These days I just love finding $7 a can powder, especially when it’s full.
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