Powder Burn Rate Chart

I have always thought that burn rate changes with pressure. That change is different for different powders.

When I put more Power Pistol or LIL'GUN or 800X in a cartridge, it may just make a bigger and bigger fireball at the muzzle.

But AA#5, which is slower than Power Pistol, acts peaky, and gets huge increases in pressure with small increases in powder, like it suddenly got a lot faster.

For this reason, I think that one dimensional powder burn rate charts are not that accurate.
 
Powder Burn Rate Chart
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They can be interesting to look at,
but that is the only thing you can do with them.
It is much more useful to find your cartridge's load data and then see which powders have published loads. Those are powders, and loads, you can use.

The powder manufacturers publish burn rate charts on their products page.
After you gather more than one, then you will notice they do NOT always agree. As to this powder being faster than the other, someone else's chart will be the other way around. And you cannot prove either is wrong: it is completely useless. :eek:

You can look up pretty much all published loads here:
http://thefiringline.com/forums/showthread.php?t=435562

http://www.accuratepowder.com/products/burn-rates/
http://www.hodgdon.com/PDF/Burn Rates - 2015-2016.pdf
 
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I think that's because they are compiled by guessing from load data, which isn't all that consistent from one source to the next. Burn rates are tested under a standard set of conditions, and since different cartridges are loaded to different pressures, those standard conditions usually don't apply exactly. Burn rate testing isn't cheap, and I doubt the powder makers actually pay to have their competition's products tested to compare to their own even at the standard conditions. So the only ranking you can be sure is correct is for each powder maker's own powders. Since Hodgdon now distributes their brand, Winchester, and IMR powders, it probably has the order right for those brands, as they specify it when they order the powder.

The was an experiment in the 1995 Precision Shooting Reloading Guide in which a 308 with 180 grain bullets was loaded to fixed velocities with IMR 4895 and IMR 4064. At low velocity (2200 fps, IIRC) it took less 4064 than 4895, suggesting 4064 was the faster powder. At 2400 fps the charge weight was the same. At 2550 fps it took more 4064 than 4895, suggesting it was now the slower powder at the pressures that produce that velocity.

The reality is just that 4064, at rifle pressures, affects pressure less per additional grain than 4895 does. 4895's burn rate is affected by difference in peak pressure more. So, how do you rank them on a table?

I think it is generally more useful to look at what cartridges and bullet weight combination a powder is typically used in. The are burn rate charts like Western's and this one are more practical from that standpoint, as each horizontal row has powders that can generally be used in the same cartridges.
 
I've got charts in my reloading manuals, bookmarked on my compiuter and a couple printed from different powder manufacturers. Interesting to look at, but pretty vague. I don't know how the powders are tested and under what conditions (as mentioned above, I believe pressure changes burn characteristics). And they just give a list of powders in order, without noting how much powder xxx is faster/slowerthan the next in line, powder yyy. For "rough" comparisons, I glance at a chart, but to determining a specific powder's place, I do more research...:p
 
I was looking at a long line of different blenders in the store.

Some have "chop" as faster than "whirl".
Some have "whirl" as faster than "chop".
 
NONE are accurate

There are lots of burn-rate comparison charts available, Many directly from the powder manufacturer's themselves (see Hodgdon's and Western Powder's web sites for just two of them).

They are all simply a rough comparison to give you an idea of how a particular powder MIGHT perform compared to others. You must NEVER substitute one powder for another simply based on where they sit on a comparison chart. Use the information on which powders may have similar burn rates to lead you to REAL load data for those powders in reliable source materials (published books, manufacturer's web sites, etc., NEVER internet postings!!).
 
No two are exactly the same but for practical purposes, rather than exact, one is as good as the next.
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. . . ^^ Well stated. ^^

Ask 100 different reliable sources to produce a burn rate chart, and you're going to get 100 different burn rate charts.

I'm just going to add my opinion real quick here:

I'm not a fan of burn rate charts that simply number the propellants from 1 to Whatever. That format implies linearity; and it's not that simple. Propellants #21 and #22 may be very close in burn rate: while #23 is much slower; and #24 is nearly the same as #23, etc. If that makes sense. But to simply number them gives the mental image of burn rates from powder to powder being a fairly straight line moving downward on a graph. They're not.

For that reason, I am a big fan of Accurate/Ramshot's burn rate chart. It's two-dimensional; and propellants that are very close, fall on the same line horizontally. For instance, AA#2, Red Dot, and TiteGroup all fall on the same horizontal row - implying that they are the same (or nearly the same) in burn rate. And it just so happens that in my personal experience, the above-mentioned example holds true.

Which brings me to the second reason why I like the Accurate/Ramshot chart: It's seems pretty darn correct, based on my personal experience.
 
I have one in my reloading book I made up. I only use it as a ruff guide line when looking for a new powder to try. I'll pick one out that is closer to powders I currently use and then research that powder further.
 
For that reason, I am a big fan of Accurate/Ramshot's burn rate chart. It's two-dimensional; and propellants that are very close, fall on the same line horizontally. For instance, AA#2, Red Dot, and TiteGroup all fall on the same horizontal row - implying that they are the same (or nearly the same) in burn rate. And it just so happens that in my personal experience, the above-mentioned example holds true.
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Nick, I mostly agree with you, but the problem is that too many newbies take that kind of comparison chart to mean that the powders on the same row are equal and can be interchanged. As we all know, this is NOT correct. So the best advice is to tell them that burn rate charts are nothing more than an approximation.
 
Page 23-24 of the Accurate 2016 Reloading Guide http://www.accuratepowder.com/wp-content/uploads/2010/09/WesternLoadGuide1-2016_Web.pdf are a Matrix of Rifle calibers as rows, and Accurate powders (including Ramshot) as the columns. If the powder is used in that caliber, then there is an X in that row and column. So you can very quickly see which powders are good for a caliber and which calibers a certain powder can be used in. This chart, in the middle of the load data, is what reloaders (especially new) should use when considering powders they can use.

The Hodgdon/IMR/Winchester reloading center http://www.hodgdonreloading.com/ gives the same information, but in a different format. You select a caliber, and bullet weight, . . click Update . . and the list of powders and their data for that bullet weight appear.
 
As stated already burn rate charts are useful to give an idea of a powders rate compared to others, it is not published load data. Kinda the same logic as to why Speer does not give pressure readings for specific loads. Synthesizing/extrapolating data is done from other data such as for plated bullets. Hard data does not exist for plated and appears the makers of plated do not have the resources or desire to develop their own data.
 
While I agree with much of the above discussion about how "useless" most burn rate charts can be, I still use them quite frequently; and have the latest Hodgdon and Lapua charts on the wall behind the computer I'm using at the moment. They're nice to stare at while I contemplate potential loads - especially for wildcat cartridges or applications of unusual components.
And, it looks like I'll be adding the Western Powders chart, since they changed format.


I find the 'multi-column array' style charts (such as Lapua, Western Powders, and Unclenick's link) to be more useful/helpful than 'classic' style charts (like Hodgdon's) where everything is ranked linearly.

Lapua chart (2011).
 
Thank you all

I have several burn rate charts from a variety of sources, and many conflict
with each other ( one says IMR4350 is faster than IMR4895 )

What I was hoping for was a more accurate up to date chart with the
newer powders

I have been looking on the internet, here and other forums

The chart I use the most was Sierra's but it is outdated, I called them
about a newer chart and a newer loading manual, they said they had
no plans for a new manual or updating the chart, "they were to busy
with other things"

At this point I will continue consulting several charts and make the
same educated guess, trial and error I have been using
 
The chart I use the most was Sierra's but it is outdated, I called them
about a newer chart and a newer loading manual, they said they had
no plans for a new manual or updating the chart, "they were to busy
with other things"
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Sierra has had that attitude for quite a while.
Back in September 2011, Matt Reams and I had few discussions. On the subject of a new reloading manual, or at least publishing some updates that can be inserted into the existing manual, the response was: 'We have no plans for a new manual. We'll be posting updates to our website and blog from now on. People can put print-outs in their Sierra manuals if they want to.'
 
I think that the bottom line is they are a ball park reference and then use reloading manuals or lit sheets for actual reload.

Some like R17 still do not appear in assessment but did make the charts.

As noted, some are listed higher in one and some are lower but they are in the same area giving you a rough idea of where they stand,
 
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