Good morning everyone,
Has anyone tried Somchem S335 in .458 Win Mag caliber ?
I know it works well in .458 Lott so I am thinking it should work well in .458 Win Mag as well ?
Roy
Here are two projections calculated in Quick Load with a 24 inch barrel and using S335 and S321. The charges are theoretical, but I have calculated to achieve the half node between Nodes 6 and 7 with a barrel time of 1.371ms. As can be seen, S335 burns quicker and pressure is high to achieve 2060fps with the 500gr bullet.
With S321 and the same barrel time speed is 2100fps and pressure is much lower. If hunting in hot weather the pressure with S335 might cause difficult extraction and therefore S321 would be better in such a situation. Recoil might also be stiffer due to faster pressure peak.
Roy -Tripodmvr has gone way past old school reloading and is resident expert on more than one site in RSA. The shit he calculates is almost magical.
The way I see it is that the bang from the 335 is much quicker and harder than the 321 bang, the reason being it was designed to get the job done in shorter barrels - burn and achieve velocity in shorter time at the cost of higher pressure.
The 321 burns longer, slower and over the length of the barrel.
Thats one thing, the other thing is the big heavy bullet offers to much resistance in the form of weight to be overcome in regard to acceleration for the 335 fast burn rate and this causes high pressures spike. The 321 burns just enough slower to not spike the pressure trying to get that 500 gr bullet moving.
Somchem are even more pessimistic regarding S335. They have proper pressure testing, whereas QL is there more or less. QL is a very handy tool to see which propellants will give the best performance.
https://www.somchemreload.com/search?c=8&f=130
I cannot help with calculations, but I do remember a thing or two from an old timer sharing his experiences ...
DO NOT - by any means, or in any way - load a compressed load in the 458 WinMag. It is not whether you might suffer terrible ignition due to caked powder, it is just when it will occur. A family member of mine culled elephants with a 458 WM and he vividly remembers the day a bullet from a reloaded cartridge sat between the eyes of an elephant cow.
DO NOT let the reloaded cartridges get older than three months. Something about angry, big footed game and poor penetration.
The 458WM is a good cartridge, but our local powders do not unlock it's full potential.
Hi guys, thanks very much for this valuable feedback and information. So what then are the most suitable calibers for S335 ?
Primary would be 308W. Some shooters find luck with it in their 223's. My 223 is much happier with S321.
Quote from: Tripodmvr on Nov 22, 2023, 12:29 PMPrimary would be 308W. Some shooters find luck with it in their 223's. My 223 is much happier with S321.
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Same findings on my side
Quote from: Ds J on Nov 21, 2023, 08:50 PMI cannot help with calculations, but I do remember a thing or two from an old timer sharing his experiences ...
DO NOT - by any means, or in any way - load a compressed load in the 458 WinMag. It is not whether you might suffer terrible ignition due to caked powder, it is just when it will occur. A family member of mine culled elephants with a 458 WM and he vividly remembers the day a bullet from a reloaded cartridge sat between the eyes of an elephant cow.
DO NOT let the reloaded cartridges get older than three months. Something about angry, big footed game and poor penetration.
The 458WM is a good cartridge, but our local powders do not unlock it's full potential.
The caking of compressed powder is only an issue with the double-based spherical powders like S321 etc.
On S335, which is a single based extruded powder, compression is not supposed to cause caking.
Quote from: 223 on Nov 22, 2023, 09:26 PMQuote from: Ds J on Nov 21, 2023, 08:50 PMI cannot help with calculations, but I do remember a thing or two from an old timer sharing his experiences ...
DO NOT - by any means, or in any way - load a compressed load in the 458 WinMag. It is not whether you might suffer terrible ignition due to caked powder, it is just when it will occur. A family member of mine culled elephants with a 458 WM and he vividly remembers the day a bullet from a reloaded cartridge sat between the eyes of an elephant cow.
DO NOT let the reloaded cartridges get older than three months. Something about angry, big footed game and poor penetration.
The 458WM is a good cartridge, but our local powders do not unlock it's full potential.
The caking of compressed powder is only an issue with the double-based spherical powders like S321 etc.
On S335, which is a single based extruded powder, compression is not supposed to cause caking.
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Yes, it is the ball propellants that cake under compression, but appears to only be a real threat under tropical type heat and/or long term storage. The ball propellants in the SOMCHEM range all end in the # "1" -221,321, etc
I've run the simulation with S321 and S335 on GRT, and they are so much of a muchness. The S335 will give you a slightly better case fill and will reach the same velocity with a grain less of powder. I would probably use S335 as a stick powder it is more temp stable, and burns cooler than a ball powder. Ball powder measures easier, but I don't think that is going to make a difference in a 458.
Quote from: Againstthegrains on Dec 17, 2023, 03:25 PMI've run the simulation with S321 and S335 on GRT, and they are so much of a muchness. The S335 will give you a slightly better case fill and will reach the same velocity with a grain less of powder. I would probably use S335 as a stick powder it is more temp stable, and burns cooler than a ball powder. Ball powder measures easier, but I don't think that is going to make a difference in a 458.
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Its that heat sensitivity that is worrying in a case as big as a .458 and then the usual part of the world where the .458 is generally used, not known for mild days where there be Buffalo and elephants.
Somchem values agree with what QL has to say. S321 is the better choice and leaves more leeway with lower pressure to accommodate hotter conditions.
https://www.somchemreload.com/search?c=8&f=130
CASE LENGTH
CARTRIDGE OVERALL LENGTH
.458 Winchester Magnum
BARREL
LENGTH POWDER CASE PRIMER BULLET
grains COL
mm
LOAD
TYPE LOAD
grain VELOCITY
ft/s V/C
factor
24" S321 W/W CCI 250 400gr SPEER FN
79.2
Start 77.3 2 372 30.7
Max 81.3 2 474 30.4
500gr HORNADY FMJ
84.3
Start 67.8 2 044 30.1
Max 71.8 2 083 29.0
S335 W/W WW 500gr HORNADY FMJ
84.4
Start 67.0 1 886 28.1
Max 70.0 1 999 28.6
S341 W/W CCI 250 400gr SPEER FN
79.4
Start 77.5 2 031 26.2
Max 81.5 2 126 26.1
500gr HORNADY FMJ
85.0
Start 73.5 1 903 25.9
Max 77.5 2 005 25.9
Wow ! Oom Drie, would excess case space not be a larger factor issue when pressures start rising ?
Quote from: Againstthegrains on Dec 17, 2023, 03:25 PMI've run the simulation with S321 and S335 on GRT, and they are so much of a muchness. The S335 will give you a slightly better case fill and will reach the same velocity with a grain less of powder. I would probably use S335 as a stick powder it is more temp stable, and burns cooler than a ball powder. Ball powder measures easier, but I don't think that is going to make a difference in a 458.
Actually, the ball powder burns slightly cooler than stick.
To muddy the waters a bit, S341 and S335 is around equally as stable. I suspect that S321 would be similar.
https://www.somchemreload.com/news/2014/09/16/influence-environmental-conditions-different-reload-propellants-same-calibre
Quote from: Tripodmvr on Dec 18, 2023, 08:27 PMhttps://www.somchemreload.com/news/2014/09/16/influence-environmental-conditions-different-reload-propellants-same-calibre
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I recall you bringing this up years ago in same subject post.
I see the issue is more Relative Humidity than temperature ?
https://www.somchemreload.com/news/2018/04/23/energy-output-ball-propellant-vs-extruded-propellant
Quote from: Treeman on Dec 18, 2023, 08:38 PMQuote from: Tripodmvr on Dec 18, 2023, 08:27 PMhttps://www.somchemreload.com/news/2014/09/16/influence-environmental-conditions-different-reload-propellants-same-calibre
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I recall you bringing this up years ago in same subject post.
I see the issue is more Relative Humidity than temperature ?
There are two pages, the other being temperature and pressure
Quote from: Treeman on Dec 18, 2023, 08:38 PMQuote from: Tripodmvr on Dec 18, 2023, 08:27 PMhttps://www.somchemreload.com/news/2014/09/16/influence-environmental-conditions-different-reload-propellants-same-calibre
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I recall you bringing this up years ago in same subject post.
I see the issue is more Relative Humidity than temperature ?
While there are effects of relative humidity. One must bear in mind where you live and where you will be doing load development and hunting. In some places there is generally a narrow range of relative humidity, and others, quite a wide range. As an example, in George, there are crazy extremes: when the mist rolls in from the sea and it rains all day, its normally around 80-90%, and when the berg wind blows from the other side, it can drop as low 30%. Now if you hunt on the highveld in winter, the range of RH is quite small, and thus negligible. However, the extremes of temperature are more relevant, up to 20 degree difference between early morning and mid day temperatures. Granted, the RH will cycle as it heats up and cools down, as the two are connected.
RH will only be of relevance during reloading and exposure of the propellant for long periods. Once the round has been sealed off by the bullet then only temperature will have an effect.
Quote from: Tripodmvr on Jan 11, 2024, 12:03 PMRH will only be of relevance during reloading and exposure of the propellant for long periods. Once the round has been sealed off by the bullet then only temperature will have an effect.
^ This. Cartridges are hermetically sealed when properly assembled.