are burn rates meaningless?

[unclebill]

i am reading my LYMAN handgun manual again and noticed that UNIQUE,UNIVERSAL and HERCO all have the same burn rates.
then i did an online search and found wildly conflicting opinions in every direction.
so should i just ignore this burn rate thing and continue to follow the directions in my manuals?

thanks
bill

[Blammer]

yes


.

[unclebill]

me comparing powders does no good because they aren't interchangeable anyway .
so why bother?
and if those tables are constantly updated .
there is no way to tell if it is the latest info or not.

[wiljen]

The simple fact is the only way to get a true burn rate chart would be to do it by cartridge and bullet. Powders react to case shape, primer strength, mass of projectiles etc... The reason you see so much variation is that the different chart makers did their testing in different manners and with different cartridges. At best burn rate charts give you an idea of what other powders MIGHT work in a given application, as for recipes - stick with the manuals.

[BCB]

I don’t understand how Unique and Herco could have the same burn rates—they are made by the same company. So why have two powders with the same burn rate? Universal is very close to Unique depending on which chart you observe.

I disagree that burn rates are meaningless. I will probably be condemned to a fate worse than death when I say that I have used burn rate charts to help work up reloads for powder that weren’t listed in some manuals. AL-8 is an example as it isn’t in any newer manuals. I’ve used data from powders that are listed as faster than AL-8 as the starting load. I have never had any problems. Maybe Lucky? I don’t know, but the burn rate charts aren’t meaningless as far as I am concerned. Good-luck…BCB

[Potsy]

I have often used a burn rate chart, a reloading manual to compare loads with, and then a chronograph to work up loads.

It helps to have a feel for powders in a given burn range, how they react in YOUR GUN, and have sense enough to start a little low.

A burn rate chart by itself is useless, kinda like a reloading manual without a chronograph.

It also depends on application; you can dump 8 or 9 grains of anything in Unique's burn range in a .45 colt with 250 grain bullets when loading for a Ruger Blackhawk and not risk life and limb. Doing the same in a modern rifle at upper end pressures requires you to be a little more specific.

[unclebill]

A burn rate chart by itself is useless, kinda like a reloading manual without a chronograph.
UNQUOTE



i disagree on that one.
1000's and 1000's of reloaders dont have a chrono.

[Four Fingers of Death]

I've used burn rates to develop loads where there were no published loads (not an issue nowadays with the internet), but I was realllllllllllllllllllllllll careful.

[wiljen]

I don’t understand how Unique and Herco could have the same burn rates—they are made by the same company. So why have two powders with the same burn rate?

Alliant does indeed have several powders with the same burn rate. The difference is in bulk density.

For example 20/28 and Unique are almost exactly the same burn rate although unique is more bulky than 20/28.

Red Dot, Promo, and e3 are all the same burn rate (you can use the same data by weight) but all have different bulk densities and will take up different amounts of case space.

20/28 was designed for small cases where there wasn't enough space to use unique.

e3 was designed for 12ga shells where Red dot takes up very little room and wasnt appropriate. e3 has a much larger grain size than red dot.

[GabbyM]

Burn rate doesn't tell you how much energy is in the powder. Nitro content is one energy source.

[Potsy]

UncleBill,
I've no doubt 1000's have no chronograph; I'm friends with a bunch of them.
I used to re-load without one and after I got a chronograph I realized that 1000's of people had no real close idea of what their loads were doing in terms of speed and, as it relates to speed, pressure.

Point being, a burn chart is only accurate in a case by case basis. A reloading manual is only exact in terms of the gun or test barrel the data was worked up in.

When working with upper end pressures in a modern rifle, a given load in a manual may not give near the speed indicated in YOUR RIFLE, or it may be way over the top in YOUR RIFLE, and your rifle may not show pressure signs as easily as others.

I didn't mean to sound like a chrony snob and didn't mean to imply reloading manuals are useless. I just meant that a reloading manual is a guide (kinda like a burn chart) and no one I hang around with is that good at guessing (within 200 fps) what a load is doing 100% of the time without verification of a chronograph.

Frankly, I'm not one of these that shoots dozens of rounds over my little $80 chrony, I might shoot 10 rounds working up a load and then 5 more after I get where I want to be. I just want to know for sure. Alot of my buddies without a chronograph have either been a little spooked about how fast they were going, and some others were sorely disappointed when they fired their loads accross my chrony.

[missionary5155]

A burn chart is another tool to use... not stake my life on. And I am looking for all the tools I can find and afford.

[mauser1959]

I find burn rates interesting , but still am mystified if they really have any basis in fact. Take for instance , I load most of my pistols with either 700X or Bullseye, and depending on the chart that you look at , either the 700X is the fastest or in another chart Bullseye is faster. I have tried to work up loads with that in mind and so far have kept myself safe , but at times I wonder exactly what is going on. I know that in my magnums that I love the 700X due to the longer perceived recoil time... but is that just my perception. I believe that I need a good Chronograph, but that is still a ways out yet, so everything now is just starting a load light and working up due to primer cartridge deformation.

[unclebill]

every time i develop a load .
it almost always end up with the most accurate one being 90% max load.
but i still always start with the min.

[James C. Snodgrass]

I'm with Potsy on the chrono . As far as charts go how many arguments and cussin' match's have we seen about H-110 or WW-296, now they say the come from the same spout and are identical ? As far as max load goes you need a chrono to find it . If the manual says 2850 fps out a 24" tube and you are getting 2900 fps from a 22 " tube you found and passed the books max . I go by speed plus expansion of cases and primer pockets if I can fire the load 8 or 10 times with tight primers you Know it is safe . But my main point is all chambers and throats are not equal so some require more or less powder . As far as revolvers and semi auto pistols and absolutely shotguns the book should be treated as scripture . James[smilie=1:






' '

[unclebill]

I'm with Potsy on the chrono . As far as charts go how many arguments and cussin' match's have we seen about H-110 or WW-296, now they say the come from the same spout and are identical ? As far as max load goes you need a chrono to find it . If the manual says 2850 fps out a 24" tube and you are getting 2900 fps from a 22 " tube you found and passed the books max . I go by speed plus expansion of cases and primer pockets if I can fire the load 8 or 10 times with tight primers you Know it is safe . But my main point is all chambers and throats are not equal so some require more or less powder . As far as revolvers and semi auto pistols and absolutely shotguns the book should be treated as scripture . James[smilie=1:






' '

AMEN BROTHER!
:mrgreen:

[unclebill]

i have looked at those charts a bunch of times but they have no bearing on what i do because i dont substitute powders.
that was one of the reasons i started this thread.
if it's not in at least one of my books.
i dont load it.

[shooting on a shoestring]

To me a burning rate chart is like a Schedule of Events for a church service or graduation. It gives you a general idea of what to expect, but don't try to use it to set your watch.

When I look at the results of my load development and find myself wanting a faster or slower powder, I take a quick look at a burning rate chart to see which powders are likely in the range I'm wanting. Then I consider powder kernal size and shape (metering ability), density, composition, and availabilty and pick a powder to investigate.

There are always powders out there I haven't tried and haven't heard of until I see them on a burn rate chart. When Promo came out I had no idea if it was for rilfe or pistol until I saw its position on the burn rate chart. Then I knew it was good for shotguns and light revolver as is Red Dot.

[GP100man]

think of the burn chart as a guide to building a pressure curve chart .
the qwiker powders have a sharper spike than the slower powders .
also consider load density .


GP100man:cbpour:

[454PB]

Here's another can of worms to open:

Never exceed published maximum loads!

Does everyone follow this rule?

I don't. I own several chronographs and micrometers. One of my recipes for my .300 WM exceeds published Winchester load data by 4 grains, yet my brass lasts 10 to 15 loadings and my chronograph records less than the Winchester results.

[missionary5155]

Published MAX loads... I would have to ask.. How come max loads were higher in load manuals 30 or so years ago than rescent manuals ? Did steel get weaker.. did machining processes get worse.. or did lawyers and frivilous law suits stick thier fingers in the pot ?
I had the the "Privaledge" to serve in 2nd Armored Div. for about a year (1972). I decided to read about Gen. Patton. He was not perfect but one of the bright things he said was" Regulations are guidelines...." Well that´s what Published MAX loads are GUIDELINES... they may be unsafe in your firearm and under powered in mine. Reloaders are suposed to be brain functional thinking people who read and head the front of the book before proceeding to the loads. Starting at the suggested low and working up observing and looking for high pressure signs for that particular firearm... Read the front of any loading manual every couple years and pay attention we may just write to each other next Thansgiving time.
God Bless you all... Say Thanks for something.. may be your last chance.

[shooting on a shoestring]

I don't drive with my foot on the floor either. For my needs I push velocity until I find the best grouping and that's always been less than full throttle. If I need more power, I go to a higher caliber.

Yes the reloading manuals today are more conservative than the 1960s, but much of that old data was not pressure tested and was based on data from a sample firearm. Firearms vary in dimensions and hence pressures. Yep they are guidelines and they are more educated, researched and couched for litigation these days. But I still use them.

[Ricochet]

They shot enough working up a lot of those old manuals' data to have significantly worn bore throats, which increases the allowable max load.

[mauser1959]

I guess that I am a bit different than most here , I work up a load till it works the best in all of my guns in that caliber (sometimes that is a chore) and that is where it stands. I will admit that when I reload for my 44 magnum that a lot of times that I load a bit lighter than is optimum but it gives me a much longer days shooting ( I reload for a few buddies and one of them wants the rounds so hot that they jar my eye teeth... but I know that each reload is for him). I have also found that by working with different powders that I get felt recoils that are more to my liking... I do not personally feel the need to get my hand slapped each time by a baseball bat to know that the round will work. So , I guess what I am really saying is that give me the optimum accuracy and ease of shooting on my body every time.

[Down South]

so should i just ignore this burn rate thing and continue to follow the directions in my manuals?

Another YES.