I recently did a web search but couldn't find any information related to ball type powders in ARs, except one who complained about loading AA2230 in a 308. I was looking for a chart!! Is there a temperature sensitivity chart on ALL rifle powders, not to be confused with burn rates. I have pretty much stayed with 8208 or H4895 for my 308/06 gas guns but plan on loading several hundred rounds of 5.56 (pressure) rounds for my Wylde chambered ARs. Extruded powders can not be efficiently loaded via powder throwers. Even Varget and 8208 have to be thrown and then weighed to be sure of accuracy. Ball type powders throw more accurately. Now, to find a ball powder that is forgiving in temperature fluctuating NW Florida weather. Please provide link, if known. THX!
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Temperature insensitive ball powder chart?
- Thread starter tank1949
- Start date
reynolds357
New member
Dont know about a chart, but you can look up individual powders.I recently did a web search but couldn't find any information related to ball type powders in ARs, except one who complained about loading AA2230 in a 308. I was looking for a chart!! Is there a temperature sensitivity chart on ALL rifle powders, not to be confused with burn rates. I have pretty much stayed with 8208 or H4895 for my 308/06 gas guns but plan on loading several hundred rounds of 5.56 (pressure) rounds for my Wylde chambered ARs. Extruded powders can not be efficiently loaded via powder throwers. Even Varget and 8208 have to be thrown and then weighed to be sure of accuracy. Ball type powders throw more accurately. Now, to find a ball powder that is forgiving in temperature fluctuating NW Florida weather. Please provide link, if known. THX!
Cold isn't the issue here. Hot weather effects powder just as much as cold and is more dangerous. Powder burns with less pressure in the cold, in hot weather it can have more pressure and what is safe at 70 degrees could be an overload at 100+ degrees.
There are only a handful of powders designed to be stable over a wide range of temps and I'm not aware of any ball powders that make that claim. Not that there aren't any. It just that all of the ones I'm aware of just happen to be stick powder. Most will show a change of 1-3 fps for every 1 degree temperature changes. But even the most stable powders will still change roughly 1/2 fps for every 1 degree of temperature change.
There are only a handful of powders designed to be stable over a wide range of temps and I'm not aware of any ball powders that make that claim. Not that there aren't any. It just that all of the ones I'm aware of just happen to be stick powder. Most will show a change of 1-3 fps for every 1 degree temperature changes. But even the most stable powders will still change roughly 1/2 fps for every 1 degree of temperature change.
FrankenMauser
New member
I know of no such chart.
--
Unless you want something that works pretty much the same from -20 F to 115 F, it really isn't an issue.
Pick a powder and have at it.
For example...
I tested about half a dozen powders from ~0 F to 104 F over the course of about 2 years, to develop the "One Load to Rule Them All" for my go-to .270 Win. (From pronghorn in September heat, to late elk in frozen Winter.
In the end, the most consistent powder for that load was actually a big, fat, extruded powder. Not only that, but it was also reported by ballisticians and self-appointed internet 'experts' to be the most temperature sensitive powder out of the bunch - RL-19.
The load still shows muzzle velocity changes that correspond to temperature, and other powders produced considerably small groups across a narrower temperature range (such as Ramshot Hunter, a ball powder, consistently punching tiny little groups [sub-1/4 MoA] from about 50-60 F); but nothing else was as consistent across the broader temperature range.
In the end, the champion was the powder originally voted "Least Likely to Succeed."
Pick a powder, or group of powders, and start testing for the particular loads that you need to develop.
--
Unless you want something that works pretty much the same from -20 F to 115 F, it really isn't an issue.
Pick a powder and have at it.
For example...
I tested about half a dozen powders from ~0 F to 104 F over the course of about 2 years, to develop the "One Load to Rule Them All" for my go-to .270 Win. (From pronghorn in September heat, to late elk in frozen Winter.
In the end, the most consistent powder for that load was actually a big, fat, extruded powder. Not only that, but it was also reported by ballisticians and self-appointed internet 'experts' to be the most temperature sensitive powder out of the bunch - RL-19.
The load still shows muzzle velocity changes that correspond to temperature, and other powders produced considerably small groups across a narrower temperature range (such as Ramshot Hunter, a ball powder, consistently punching tiny little groups [sub-1/4 MoA] from about 50-60 F); but nothing else was as consistent across the broader temperature range.
In the end, the champion was the powder originally voted "Least Likely to Succeed."
Pick a powder, or group of powders, and start testing for the particular loads that you need to develop.
We don't get real extreme temp swings here but I shoot ball powder in all of them, mostly BL-C(2) and W748. Personally I think it mostly matters if ammo is left in the sun or a round sits in a hot rifle for a while before firing. The only time I've felt like temperature was probably an issue, I had been carrying the chambered rifle on my back in the sun for an hour on a hot day, after firing the bolt was sticky on extraction (it was already a max load in .204 Ruger). A half hour cool down in the shade and that went away.
When I shoot a XTC match I keep my ammo boxes in the shade. Usually not firing fast enough to really heat up the barrel either.
When I shoot a XTC match I keep my ammo boxes in the shade. Usually not firing fast enough to really heat up the barrel either.
The military uses the same ammo from -60 degrees, to well over 120 degrees. AFAIK, they haven't blown up any rifles.
Certainly there will be slight velocity variations, but judging from the experiences of many millions of soldiers firing many hundred billions of rounds of ammo, not enough to cause problems.
Certainly there will be slight velocity variations, but judging from the experiences of many millions of soldiers firing many hundred billions of rounds of ammo, not enough to cause problems.
Tank1949,
The only temperature-stabilized spherical propellant on the market is the new Winchester StaBall 6.5, which is a little slow for the 5.56. It is intended for the 6.5 Creedmoor, which has a smaller expansion ratio cartridge than 223 in a standard 24" pressure and velocity test barrel. That gives a slow powder more time to reach peak pressure before expansion causes pressure to drop.
In stick powders, temperature sensitivity is controlled by manipulating the deterrent coatings. This is made possible by the fact progressivity of the burn can be independently adjusted by the grain geomethery (grain size and the number and size and configuration of perforations in it). With spherical powders, progressivity is controlled entirely by how the deterrent coating concentration falls off as the grains burn from the outside inward. There is no equivalent to a perforation to control progressivity independently of the deterrent control. For that reason, the Western Powders site FAQ says spherical powders cannot be made temperature insensitive. So, what has General Dynamics done to make the StaBall 6.5 parent powder temperature insensitive? I have no idea. They've pulled off quite a hat trick there. I don't doubt they developed it for the military because of the scheduled deployment of the 6.5 CM for snipers this year (as well as for a number of other military arms as their new medium power cartridge). Winchester or Hodgdon (Winchester's distributor) was smart enough to get it made in canister grade for handloaders. I expect it will prove popular. I have no idea whether GD will eventually develop a parallel product for the 5.56 or not.
For stick powders, the Hodgdon Extreme line and the new IMR Enduron powders are the main choices available for temperture stability. Alliant Reloader 15 claims stability, but the military had some issues with it in desert temperatures and good old IMR4064 did better. The newer Reloader 16, though, claims "world class" temperature stability, so it is probably a better bet from that company's line.
All the non-compensated powders can be compensated for approximately by the formula built into QuickLOAD as to temperature effect.
Be aware that temperature compensation in powders depends on them being in a cartridge that produces a certain range of pressure and rate of pressure rise and those are affected by case capacity and bullet weight. Varget, for example, seems to do pretty well in many .308 Winchester loads, but in .223 Rem most folks say they can't tell it from any other powder. This article is informative.
As to not being able to dispense stick powder volumetrically, this is misleading and also untrue if you have the right measure. The JDS Quick Measure is guaranteed to keep them within ±0.2 grains and often does better. I've been using one for several years now, and can confirm that performance. A second factor is that stick powders burn more slowly when the grains are packed closer together because the ignition flame front has a harder time moving through the resulting tighter spaces between the grains. For this reason, the right stick powder, when the measure throws it heavy, can impart the same velocity to the bullet as a lighter charge of the same volume. Like temperature compensation, how well this works depends on matching the right stick powder to your cartridge and bullet combination for best effect. When I pulled down a box of Federal GM308M, I found the IMR4064 inside had a 0.4-grain weight span. Board member Statshooter did the same and found a 0.6-grain span. It shoots just fine.
Finally, why weight over volume? Weight is a more precise measure of the amount of chemical potential energy being dispensed into a case if the powder is kept and dispensed in reasonably stable relative humidity. If the humidity changes from low to high, the weight of the powder increases up to 1.5%, so your scale can under-measure potential energy by that much in humid conditions. But the volume of the grains doesn't change with that added water content (it doesn't swell) so a carefully used volumetric measure can actually dispense energy content more accurately under that circumstance. But then there is another problem. As the Norma manual says, powder burn rate can increase by 12% going from 80% RH to near 0% RH. So even if you keep the energy dispensed the same, powder that gets too dry can take you right out of a load sweet spot. The bottom line is to keep your RH constant at about where the powder makers keep their stocks because that's the RH that their load data will have been developed with. 60% is a good compromise between what the various distributors report having. Norma also points out that water molecules are small enough to slip past primers and bullets in unsealed cases. If you change the RH you store your cartridges in, expect the powder to gradually start reflecting that change over a period of about a year, at which point it will behave as if the powder had been stored in that new RH all along. For this reason, you never want to desiccate loaded cartridges in storage and you don't want to desiccate your powder unless you don't mind published load data for it becoming invalid.
The only temperature-stabilized spherical propellant on the market is the new Winchester StaBall 6.5, which is a little slow for the 5.56. It is intended for the 6.5 Creedmoor, which has a smaller expansion ratio cartridge than 223 in a standard 24" pressure and velocity test barrel. That gives a slow powder more time to reach peak pressure before expansion causes pressure to drop.
In stick powders, temperature sensitivity is controlled by manipulating the deterrent coatings. This is made possible by the fact progressivity of the burn can be independently adjusted by the grain geomethery (grain size and the number and size and configuration of perforations in it). With spherical powders, progressivity is controlled entirely by how the deterrent coating concentration falls off as the grains burn from the outside inward. There is no equivalent to a perforation to control progressivity independently of the deterrent control. For that reason, the Western Powders site FAQ says spherical powders cannot be made temperature insensitive. So, what has General Dynamics done to make the StaBall 6.5 parent powder temperature insensitive? I have no idea. They've pulled off quite a hat trick there. I don't doubt they developed it for the military because of the scheduled deployment of the 6.5 CM for snipers this year (as well as for a number of other military arms as their new medium power cartridge). Winchester or Hodgdon (Winchester's distributor) was smart enough to get it made in canister grade for handloaders. I expect it will prove popular. I have no idea whether GD will eventually develop a parallel product for the 5.56 or not.
For stick powders, the Hodgdon Extreme line and the new IMR Enduron powders are the main choices available for temperture stability. Alliant Reloader 15 claims stability, but the military had some issues with it in desert temperatures and good old IMR4064 did better. The newer Reloader 16, though, claims "world class" temperature stability, so it is probably a better bet from that company's line.
All the non-compensated powders can be compensated for approximately by the formula built into QuickLOAD as to temperature effect.
Be aware that temperature compensation in powders depends on them being in a cartridge that produces a certain range of pressure and rate of pressure rise and those are affected by case capacity and bullet weight. Varget, for example, seems to do pretty well in many .308 Winchester loads, but in .223 Rem most folks say they can't tell it from any other powder. This article is informative.
As to not being able to dispense stick powder volumetrically, this is misleading and also untrue if you have the right measure. The JDS Quick Measure is guaranteed to keep them within ±0.2 grains and often does better. I've been using one for several years now, and can confirm that performance. A second factor is that stick powders burn more slowly when the grains are packed closer together because the ignition flame front has a harder time moving through the resulting tighter spaces between the grains. For this reason, the right stick powder, when the measure throws it heavy, can impart the same velocity to the bullet as a lighter charge of the same volume. Like temperature compensation, how well this works depends on matching the right stick powder to your cartridge and bullet combination for best effect. When I pulled down a box of Federal GM308M, I found the IMR4064 inside had a 0.4-grain weight span. Board member Statshooter did the same and found a 0.6-grain span. It shoots just fine.
Finally, why weight over volume? Weight is a more precise measure of the amount of chemical potential energy being dispensed into a case if the powder is kept and dispensed in reasonably stable relative humidity. If the humidity changes from low to high, the weight of the powder increases up to 1.5%, so your scale can under-measure potential energy by that much in humid conditions. But the volume of the grains doesn't change with that added water content (it doesn't swell) so a carefully used volumetric measure can actually dispense energy content more accurately under that circumstance. But then there is another problem. As the Norma manual says, powder burn rate can increase by 12% going from 80% RH to near 0% RH. So even if you keep the energy dispensed the same, powder that gets too dry can take you right out of a load sweet spot. The bottom line is to keep your RH constant at about where the powder makers keep their stocks because that's the RH that their load data will have been developed with. 60% is a good compromise between what the various distributors report having. Norma also points out that water molecules are small enough to slip past primers and bullets in unsealed cases. If you change the RH you store your cartridges in, expect the powder to gradually start reflecting that change over a period of about a year, at which point it will behave as if the powder had been stored in that new RH all along. For this reason, you never want to desiccate loaded cartridges in storage and you don't want to desiccate your powder unless you don't mind published load data for it becoming invalid.
reynolds357
New member
Staball 6.5Cold isn't the issue here. Hot weather effects powder just as much as cold and is more dangerous. Powder burns with less pressure in the cold, in hot weather it can have more pressure and what is safe at 70 degrees could be an overload at 100+ degrees.
There are only a handful of powders designed to be stable over a wide range of temps and I'm not aware of any ball powders that make that claim. Not that there aren't any. It just that all of the ones I'm aware of just happen to be stick powder. Most will show a change of 1-3 fps for every 1 degree temperature changes. But even the most stable powders will still change roughly 1/2 fps for every 1 degree of temperature change.
I dont see where you have a real problem. N.W. Fl gets hot but not real cold. The problem is temp swings. The desert where its freezing at 6 am and 100 at 4pm is where temp sensitivity is important.
Thanks to all and very informative. Unfortunately, where I live temperatures fluctuate. My powder thrower is a Redding so-called "Match" powder dispenser. But, I have weighted 1/2 grain differences using Varget. 4831 yields 1 full grain difference. Ball powders are very accurate in it < +-.1 grain. Perhaps technology hasn't caught up to my needs. THX again!
reynolds357
New member
Yeah, but I am always looking for simplification. If I can get better velocity, eaual accuracy, and temp stability from a new powder then I will switch to it.Hells Bells!
Doesn't anyone shoot year round anymore and keep a dope sheet?!
"Temp insensative"=lazy!
Lets dont forget snti CU fouling additives.
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From my experiences and data, my most temp SENSITIVE powder is W748. Loading typical 308 or gas gun AR , i'll observe about a span of 50 fps in velocity from June vs october. Its not a super big deal as i have gathered enough data to know to adjust my powder charges based on the ambient temps.
Again, throw accuracy is less critical with stick powders for the reasons I described earlier. Prove to yourself that your loads are performing poorly before you spend a lot of money on additional equipment. Your Redding is a good measure (I have one) but it takes practice and employing extra baffles and the like to get more consistency from it with stick. You can also modify the chamber throat to reduce cutting and the associated irregularities. I already mentioned the JDS Quick Measure, but I also have one Lee Perfect and the classic cast version of that measure that do pretty well with sticks. It's part measure and part technique.
The JDS quick measure link is dead. However, one thing that I didn't mention and I am sure every 5.56 reloader has experienced are powder jams inside powder throwers trying to throw powder into a small 5.56 hole. Stick powders are horrible. I stopped using my dillion's auto-powder dispenser because of jams. It is ok for pistol small grains and large case openings, but I still have to carefully observe for squib or overfill loads. For those reasons, I use the Redding on a separate powder filling process and sleep well knowing I examined all cases for fills. Squib loads suck!
Tank1949,
I clicked on the link and it took me straight to the site. Let me give it to you in text so you can copy and paste it into your browser.
https://www.quick-measure.com/
You can usually resolve the throw jams with a drop tube.
I clicked on the link and it took me straight to the site. Let me give it to you in text so you can copy and paste it into your browser.
https://www.quick-measure.com/
You can usually resolve the throw jams with a drop tube.
I've already did web search and found it. Interesting!!!! About 200 bucks. I may buy it just to try it out, but the small .223/5.56 brass hole is still going to cause "bridging" with stick powder unless I use long powder tube and thump it as powder goes through it (been my experience) . The 5.56 rounds are the ones I want reload a bunch of. Probably KKs. I may just stay with aa2230, since I have used it a lot in the past. The 5.56 62 grain FMJs are not too accurate anyway (maybe 2 MOA) , but I was hoping to at least get some ball powder not temp sensitive. I had read article before on temperatures affecting chamber pressures. Still a good read! I use a lot of IMR 4831 but when I do it is usually shooting at deer and cold. My 30 cals are all 8208 or H4895. Thanks for your information.
reynolds357
New member
Load the .204 Ruger a while and you will appreciate how friendly the 223 actually is.The JDS quick measure link is dead. However, one thing that I didn't mention and I am sure every 5.56 reloader has experienced are powder jams inside powder throwers trying to throw powder into a small 5.56 hole. Stick powders are horrible. I stopped using my dillion's auto-powder dispenser because of jams. It is ok for pistol small grains and large case openings, but I still have to carefully observe for squib or overfill loads. For those reasons, I use the Redding on a separate powder filling process and sleep well knowing I examined all cases for fills. Squib loads suck!