Bismuth question

A

Andy Cross

New member
I know it states in the BR rule book that lead shot cannot be used to fill rear bags. It would be interesting to know why.

In any case a friend who is always looking for some way to bend the rules in anything he does said why not use fine irregulat sized bismuth in the bag. Irregular sized garnules would behave in much the same way as irregular sized zircon sand does and not leak out the deams of the bag , has a similar density to lead but doesn't break the rules.

Anyone done this ?

Andy
 
i use

the black mineral sand stuff hard to get unless your in the right place and ask the right person.dont know what its called
 
Andy Cross said:
I know it states in the BR rule book that lead shot cannot be used to fill rear bags.

In any case a friend who is always looking for some way to bend the rules in anything he does said why not use fine irregulat sized bismuth in the bag. Irregular sized garnules would behave in much the same way as irregular sized zircon sand does and not leak out the deams of the bag , has a similar density to lead but doesn't break the rules.
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Andy,

I'm not sure what BR rule book you're looking at, but the NBRSA rule book clear says the rear bag must contain a "dry finely divided nonmetallic substance."

Ryan
 
Fred J said:
How can Lead shot be considered metallic, when it's non-magnetic?
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There are probably more non-magnetic metals than there are magnetic ones.
Copper, Aluminum, Lead, Tin, Bismuth, Magnesium, Gold, Silver, etc..... Even quite a few Stainless Steels are non-magnetic.

Although I can't use it in a competition bag - I have access to quite a lot of finely cut, sand grain sized slugs of plated copper. And I can get it for (almost) free, since it's a waste byproduct of a manufacturing process. I just have to let it sit in a tumbler for a while to dull the sharp edges.

I'd like to get hold of some Bismuth though. But it's not cheap. It's what gets alloyed with Lead and Tin to make CerroSafe alloys that can be melted in boiling water.
 
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Andy Cross said:
I know it states in the BR rule book that lead shot cannot be used to fill rear bags. It would be interesting to know why.
Click to expand...
I don't know why anybody would try. I'm not a competitive shooter so I can put anything I want into my rear bag. I tried lead shot and found that *nothing* I did could coax that shot up into the ears of the bag.
 
IMO the only place that materials that are heavier than common sand have a place in our bags is in the main chamber of the rear bag, not the ears, or the front bag. Materials that are rounded do not stack with any stability, but rather depend on the shape of their container, and degree to which it is full for retention of shape. On the other hand, more angular shaped particles can have stacking and packing characteristics that are more independent of their containers, and the degree of fill.

Dave Dohrman did some experimenting in this area and came to the conclusion that a blasting medium that was made from finely divided coal slag, had very good packing and stacking characteristics. Here is a link to what I believe to be that product, although I am not sure if it is the same granulation or even if more than one is available. http://www.reade.com/component/cont...ineral-abrasive-mil-a-22262-ca?q=black+beauty
I also seem to remember something about him mixing this material with heavy sand, although the details escape me.
 
Boyd, McMaster Carr has it available in two mesh sizes, 12-40 and 20-40.
It comes in 50 and 80 lb bags. Cost is under $20.00
Remember this material has sharp edges as we use it to sand blast.
Centerfire
 
Your right

Fred J said:
How can Lead shot be considered metallic, when it's non-magnetic?
Click to expand...

Your right. You wouldn't be allowed to use rutile sand containing zircon or anything else if that was the case. From what I gathered he used bismuth grainules in the base and mineral sand in the ears. I do remember that the bag was substantially heavier than it would be just filled with mineral sand. Which makes sinse when you look at where bismuth is on the periodic table.
Andy.
 
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