BP binder vs no binder

[MadMat]

Has anyone ever did a burn comparison of BP corned without any binder to BP granulated with dextrin binder?

Up until now, I have always corned my BP without any binder. I have been getting excellent results, but it's a lot of work. I was planning on making up a batch with 4% dextrin and granulate to compare, but if anyone else has......

[AzoMittle]

I'll do it if you can give some guidelines on how you want it done, I can't fire anything into the air though.

[Nessalco]

Mad, I make both corned BP and BP granulated with alcohol + 3% red gum. In my experience the corned burns slowest, the granulated next, then MCRH are the fastest.

 

Kevin

[starxplor]

Mad, I make both corned BP and BP granulated with alcohol + 3% red gum. In my experience the corned burns slowest, the granulated next, then MCRH are the fastest.

 

Kevin

 

Redgum? I have always heard to use dextrin when granulating BP.

[Sparx88]

It's preference. If you got it use it if not dextrin and water/alcohol is fine. I like to think that the use of water also enhances the kno3's ability to be absorbed into the charcoal more effectively. 3-5% is popular, I use 2%. Just enough to help keep the grains from breaking down into fines. I sure you already know this though.

I tried the corned route once and that was enough for me to decide on ricing through screens. In cannons and firearms corned is much more important for safe use/consistency and handling under heavy confinement. Again common knowledge, just wanted to give the best answer I could for those who don't know.

Edited October 31, 2016 by Sparx88

[memo]

for making my burst bp I use no binder and granulate with alcohol. it is not super hard , it is fast

 

memo

[MadMat]

I milled up a 100 gram batch with 4% dextrin last night. I also pressed and corned about 300 grams yesterday. Today I plan granulate the dex/bp through a screen. I will post my comparison results for anyone interested. I suppose I could do a straight line burn speed test and/or a baseball launch. I don't know if I could get much faster on the line burn speed than the stuff I corned yesterday. With some of the fines, I made a line 7-1/2" long (approx. 1.5-2 grams worth). The line burned up almost instantly in a noisy poof.

[Nessalco]

I use sumac charcoal to make BP, and the product is very fast. I use corned for lift, granulated for break in small shells, and 6:1 MCRH for breaking larger shells. It all hits hard, but the corned powder burns enough slower that it doesn't damage the guns or racks.

 

Here's a vid of my fastest product, the 6:1 MCRH. The other forms go up with a whoosh rather than a report. This BP is bound to the rice hulls with 5% dextrin.

 

Edited October 31, 2016 by Nessalco

[memo]

and that is how you make fast bp.......

[Sparx88]

I milled up a 100 gram batch with 4% dextrin last night. I also pressed and corned about 300 grams yesterday. Today I plan granulate the dex/bp through a screen. I will post my comparison results for anyone interested. I suppose I could do a straight line burn speed test and/or a baseball launch. I don't know if I could get much faster on the line burn speed than the stuff I corned yesterday. With some of the fines, I made a line 7-1/2" long (approx. 1.5-2 grams worth). The line burned up almost instantly in a noisy poof.

Why not just cut a 4" square of printer paper and 1gm lit in the center. It's one I use because it's repeatable. Use incense stick, skewer, twig just stay away from the temptation to use a torch or fuse, or worse a lighter. Just a nice 1gm pile and touch it with a glowing tip Then show us.

Edited November 1, 2016 by Sparx88

[Wiley]

The crudest test I can suggest which still gives a ballpark estimate of what you have is to take 3g of your mill dust and lay it out in a nice even powder train diagonally across a piece of flat, un-creased printer paper. Light it "gently" (no propane torches) from one of the extreme ends, and video it. Count frames or use some free software (Avidemux) to determine how long it takes for the flame front to travel that distance.

 

In my experience and that if others, a 0.4 to 0.5 second time is "good" powder. Of course you can ruin that when you process it, but if you're screen granulating, just make sure it dries in under 24 hours, but dry it for more for insurance. Doing so should give you good powder. If you want to know for sure, you'll need to do some baseball or PVC shuttle tests.

[memo]

I use sumac charcoal to make BP, and the product is very fast. I use corned for lift, granulated for break in small shells, and 6:1 MCRH for breaking larger shells. It all hits hard, but the corned powder burns enough slower that it doesn't damage the guns or racks.

 

Here's a vid of my fastest product, the 6:1 MCRH. The other forms go up with a whoosh rather than a report. This BP is bound to the rice hulls with 5% dextrin.

 

 

Nessalco

have you been able to reproduce this test and get the same results with a different batch of powder ?

[MadMat]

I did some baseball launches to compare pressed and corned powder with no binder to powder with 4% dextrin and riced through a 10 mesh screen. The baseball I used weighed 146.8 grams and I used 13 grams of each powder. The flight times are: pressed and corned 9.57 seconds,

riced with 4% dex. 9.22 seconds. I did a third launch but lost the ball so I didn't get a time, but either way, I feel the flight times were close enough so that I am going to save some effort and time by using a binder and ricing my powder from now on.

 

Both powders were made with willow charcoal and ballmilled for 3hours 45 minutes.

Edited November 1, 2016 by MadMat

[Seymour]

If I'm not pressing and corning, which is just KNO3/Charcoal/Sulfur I add 2% Gum Arabic and granulate the wetted powder/dough though a kitchen grater.

 

Of course adding binder can slow the burn but as the baseball tests shows it is not by very much. You can make far better powder that has 5% dextrin added with good charcoal than you can with average charcoal and no binder.

 

The extra strength in the grains is fully worth the small loss in performance. Sure it does work with no binder, but it is FAR more dusty, and repetitive handling of the grain or fireworks containing it will start to damage the grains.

 

While Dextrin is absolutely fine, indeed great, I do find Gum Arabic is superior. I once tried to scrape off the dried BP + 2% gum arabic of the container I used to mix the powder with the water before granulating and a thin flake that was on the wall acted as a rather good knife and cut about 5mm in to my finger. While it by and large did not break off inside me, whatever fragments that did, or KNO3 that dissolved in it's moment in me caused it to hurt a hell of a lot.

[MadMat]

Yep, KNO3 in a cut will sting a bit!

[OldMarine]

KNO3 and pvc cleaner are the best cut locators I know of!

[FlaMtnBkr]

How did you time the baseball test? With a stop watch? Or by video? If using a stop watch you need to do it at least 3 times and average and if you have a abnormal time you should probably throw it out and do another.

 

Your reaction time can vary quite a bit and with a baseball test you are introducing this error twice.

 

The corned powder should be slower by a noticeable amount unless your wetted and granulated powder just took a really long time to dry as this will also slow it down by a noticeable and even significant amount if allowed to stay wet and dry over a few days instead of hours. I like to put my granulated BP in a thin layer around a 1/4" onto a plastic tray and set in the sun when it's directly overhead. If it's partly cloudy I will even add a fan and with a stir once or twice it's completely dry in a couple hours. Throw a handful in a clear bag if you aren't sure if it's dry yet and if there is any moisture you will know in about a half hour when it shows up as a haze of condensation inside the upper areas of the bag.

[MadMat]

I timed the flight with a stop watch from boom to thump (you could hear the baseball hit the ground). I planned to do about three rounds, but the sun was going down and I lost the baseball on my third launch. the last launch was the corned powder and the time was 9.51 seconds. I guess if you average that out you get 9.54 seconds. I imagine that the time difference between the two powders would have been negligible if averaged over three rounds. With the corned powder, I semi-dry the pucks in my drying chamber (a slightly modified food dehydrator), corn them and then back into the drying chamber. The granulated powder was done pretty much the same; rough granulated, drying chamber, finish sizing and back into the chamber. both were dried as quickly as possible and completely dry (checked the weight). I wasn't too concerned about the actual times as much as a comparison between the two methods. In this respect I believe I got a valid answer.

Edited November 3, 2016 by MadMat

[pyrojig]

Nessalco: am I correct your using poison sumac for charcoal ??? That just gives me the wilies thinking about it. In itching to know more ( no pun intended)

[OldMarine]

Not poison sumac but rather Staghorn Sumac. Completely unrelated.

https://en.m.wikipedia.org/wiki/Rhus_typhina

Edited November 4, 2016 by OldMarine

[MadMat]

You can make tea from the berries of Staghorn sumac. It tastes a little like pink lemonade; Its pretty good. And it makes great charcoal too! I used to see it all over the place when I lived in Wisconsin, It doesn't really grow here in Missouri much