Peret's BP-Silicon Prime

[AzoMittle]

Name of composition: BP Prime
Creator: Peret

The Composition:

40...Potassium Nitrate (Milled)

40...Silicon (Not Milled)

20...Black Powder (Milled)

Dextrin as needed

 

Or, given directly:

 

55...Potassium Nitrate

40...Silicon

03...Charcoal

02...Sulfur

Dextrin as needed

Precedure/Preparation:

 

It doesn't need milling but the ingredients should be fine powders.

 

I pre-mill all my nitrate and perc oxidizers to flour before I use them for anything, so my version of the prime above uses 20% ball milled BP, 40% ball milled KNO3 and 40% silicon out of the bag. I never tried making a green mix prime with crystalline KNO3. However, theoretically all you need is for the prime to take fire instantly from the burst - it doesn't have to burn very fast, and indeed it won't with all that silicon. I had 100% success with the silicon prime this year, reliably lighting the difficult barium nitrate stars that blew blind in the past, though looking at the videos, those stars don't actually start to burn until they're some distance from the center of the break.

 

--- http://www.amateurpyro.com/forums/topic/6506-conventional-prime/?do=findComment&comment=84656

 

[BengalFlair]

I think Peret is not the creator of this prime.The actual prime composition is in "PYROTECHNICS" by Alexander P. Hardt which is as follows-

Potassium nitrate--38

Silicon--38

Meal D--19

dextrin--5

 

Peret just modified it a bit.

[dagabu]

I think Peret is not the creator of this prime.The actual prime composition is in "PYROTECHNICS" by Alexander P. Hardt which is as follows-

Potassium nitrate--38

Silicon--38

Meal D--19

dextrin--5

 

Peret just modified it a bit.

 

Then it becomes his version. I don't think Hardt came up with the prime either but a variant.

[Mumbles]

Nope, neither Hardt nor Peret came up with this composition. 38:38:19:5 is the exact same as 40:40:20 +5 dextrin to within a tenth of a percent for what it's worth, no modification. I got this formula 10 years ago from someone who's had it since probably the mid 80's to early 90's, and he certainly wasn't the innovator either. I don't know who actually created it, but I had it labeled as "English hot prime".

 

In any case, this is a supremely hot prime. If it doesn't light your composition, I'm not sure anything will.

[BengalFlair]

I do use this prime and agree that practically there is no difference between 38:38:19:5 and 40:40:20 +5 dextrin.

But when I got this prime composition as 38:38:19:5, I didn’t have any digital balance and only had some 100, 50, 20,10 and 5 gram weights. So I MODIFIED the composition by rounding up the numerical values as 40:40:20 +5 dextrin to weigh it easily.

I think Peret might think so ...as...Wise men think alike

[dangerousamateur]

How does this compare to the much more expensive perchlorate primes?

 

Does silicone make any trouble when wetted with nitrate?

[DonCopal]

Does the prime require an additional outer prime to ignite reliably?

[Arthur]

I've seen this prime quoted as BP +5% Si, unmilled BP ingredients +5% Si and lots of other variants. It really only depends on the fact that burned Silicon is Silica which is a liquid as created so as the liquid cools to solid slag it gives out a lot of heat to the material in contact (the star) rather than spreading hot gas into the atmosphere.