Jump to content
APC Forum

BP issues


MeowMix

Recommended Posts

Ive recently had some issues with my milled BP:

 

I mill my chems (75/15/10) in a small harbor freight mill with 2.5lb of lead media. The meal comes out fine, and when used on mcrh, it breaks perfectly. I started running into issues when I attempted to use the mcrh as lift (It did not lift nearly high enough). I was using 12% on a 3" shell and it only reached around 100ft. I then attempted milling again and granulating. These did not work either.

I milled each batch for 8 hours using commercial air float, and kno3/sulfur from pyrochemsource.

Link to comment
Share on other sites

Commercial air float will always make poor BP. Try using cedar, willow, or even while pine.
Link to comment
Share on other sites

Also your jar is underfilled. I agree it's mainly the charcoal though.

The mill is 3lb and the whole jar is already at 4.5lb with comp, so I don't really wanna go past that point.

Link to comment
Share on other sites

The pound rating refers rocks, and has little to do with the actual motor capacity. You may need to give it a push start, or add the jar after it's already spinning. A 1 gallon jar is often called 15lb, yet we have no qualms about putting 35lbs of lead, plus 2.2lbs of BP, plus whatever the jar weights on those things.

Link to comment
Share on other sites

The pound rating refers rocks, and has little to do with the actual motor capacity. You may need to give it a push start, or add the jar after it's already spinning. A 1 gallon jar is often called 15lb, yet we have no qualms about putting 35lbs of lead, plus 2.2lbs of BP, plus whatever the jar weights on those things.

I'll keep that in mind. I'm gonna order some new charcoal - paulownia charcoal is the only hardwood option; should I buy that?

 

Thanks

Link to comment
Share on other sites

Paulownia is the primo stuff! Equal to if not better than willow and cedar.

Link to comment
Share on other sites

Paulownia is the primo stuff! Equal to if not better than willow and cedar.

Thanks! I'll try that and some homemade red cedar and see what I get.

Link to comment
Share on other sites

Paulownia is the best, in my opinion. I would rate it the 'fastest' of all the charcoals that I have tried. This will make a huge improvement for you..and will probably do the trick. Also something to note. If you are using ball shells, I have found that some 3" hemispheres are slightly smaller than others. Not sure why, but they are. This causes a little more clearance between the shell and the mortar, and can render the lift less efficient. Therefore, long ago I started lifting all 3" shells with 30g of lift, regardless of the weight of the shell. That way I am hitting 300ft no matter what. It's about impossible to over-lift a 3, so don't worry about a little too much lift.

Link to comment
Share on other sites

I've run into another issue, I now have 5lb of media (all I have) in my mill, and I milled some new bp with new charcoal but when I took it out, it was all clumped at the bottom. I'm assuming its from moisture in the chemicals. All that was changed was the char, how would I prevent that?

 

Also, will it affect the performance of my bp?

Link to comment
Share on other sites

How long did you mill it? Charcoal sucks up atmospheric moisture so I keep a sock full of silica in the bucket as with my nitrate. If you milled it too long it will likely clump whether moisture is present or not. If there are no pieces of media trapped in the "mill-berg" and you can crush it to impalpable dust with your fingers I'd go with it. If I run my Hobfir mill more than 4 hours I get clumping no matter what I do beforehand.

Link to comment
Share on other sites

8 hours

Ill try adding silica to my chems and do another batch in the future

There was no media in the and it crushed very easy

Thanks :3

  • Like 1
Link to comment
Share on other sites

Note, I doubled my media from my last milling which also ran 8 hours (last mill had commercial airfloat instead of paulownia, didn't clump)
Link to comment
Share on other sites

Just adding my 2 cents; I agree with everyone. Commercial air float makes slow BP. It's BP, and it works for lots of stuff, but it's not fast. I had horrible BP until I figured that out, now it's great.

Link to comment
Share on other sites

Commercial airfloat makes good stars and glitter to.

Link to comment
Share on other sites

Just tested 30g per shell (200g) (I know it's quite a bit) and they each lifted easily over 250ft. Thanks for the help guys!
Link to comment
Share on other sites

×
×
  • Create New...