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Discussion Starter #1
I live a skip, a hop and jump from the Grande Canyon. The State/Feds are trying to restore California Condor populations in that area. Those are the same pretty birds that led to unleaded bullets throughout much of California for hunting. Special interest groups are pushing for the same unleaded bullet policy here in Arizona because we love Condors. Ultimately, it is the goal of the environmental groups and the feds to restore the Condor to the full extent of it's original range which is the east slope of the Rockies from New Mexico/West Texas all the way into Canada and everything westward to the Pacific. So if you live west of the big muddy, you may have the call to unleaded hunting bullets coming to your neighborhood some day, if these good people have their way.

Currently, the State of Arizona has adopted a voluntary lead free bullet policy for hunters. The State is pushing the use of unleaded bullets, but suggest you can also bury or haul out the gut pile. A coalition of environmental groups has the state of Arizona and Utah in court trying to force the states to strengthen the lead free policy such that it becomes mandatory backed with heavy penalties.

I seriously enjoy using cast bullets in my 444 and I have a decent collection of 444 compatible 44 cal bullet molds. I enjoy casting bullets for and shooting my 336 30-30 as well. So the thought of a future where my hard cast bullets become illegal, left me considering alternatives to lead. I have been looking at the issue for a couple of years now and people, like Flat Top, have suggested that I look into bismuth.

This is already getting long, so I will post this and continue.
 

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About a month ago, I ordered some bismuth from Rotometals at the low discount rate of $20 a pound. 5# = $100. $100 for half a fill of a 10# pot. Yikes! On top of that, this is a discount price. Rotometals say that they are selling it for a low rate to encourage bullet casters to buy it and test it. OK. So (not to get ahead of myself) after some early testing, I wrote an email to Rotometals mentioning some of the details that I am finding and to ask them questions. The response I got back was something along the lines of "Thanks for the report, I'll share your data with the staff." That's it, they didn't even attempt to answer any of my questions. So it's like, "thanks, you're on your own".
bismuthingots007_zps2eb7116c.jpg
bismuth ingots with one wheel weight alloy ingot for comparison.
 
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Well you have already found out why there is not much info on bullet casting with bismuth, darn stuff is expensive! I’ve used it as well as wood’s metal, field’s metal and cerrosafe but only for specialized castings and such. All super neat materials but until of late are just to expensive for general bullet castings. Leave it to the tree huggers to drive up costs even more !!! Hope you find a nice blend that suits your needs.
 

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Discussion Starter #6
Now let me get to working with bismuth. I had to use a brand new pot to prevent cross-contaminating my lead free alloy with lead and waste $.

Right off, it is obvious that the alloy melts at a lower temp than lead alloys. I am not sure exactly the temperature at which it melts, but it was somewhere between 425-475 degrees, I think. Probably at the low end of that range.

The alloy fills the mold quite nicely, but it takes a lot longer to cool. The Sprue probably takes 30 seconds or so to cool enough to cut the sprue. I have water dropped and air cooled and I do not notice much if any difference in hardness tests. The bullets are very bright and shiny and fills perfectly into square edges in the mold making a very sharp looking bullet.

Oh'yea, I forgot to mention that the alloy that Rotometals sells as a bismuth alloy for bullet casting is 93% bismuth and 7% tin. The alloy measures in the 13.5-14 bhn range. The first bullets that I cast were RD432-240, so I am using a proven bullet that doesn't use to much alloy in testing. With my wheel weight alloy, the RD432-240 drops bullets that weigh 249gr with GC and lube. The same bullet with bismuth is about 10% less weight with gas check and lube weighing about 224gr.

With bullets cast, lubed and gas checked, I loaded one up with 47gr of H4198 and took it to the field to test it into the jugs. My thought is, there isn't any sense in testing for accuracy with the alloy until I can verify that the alloy will work in terms of terminal performance. I was aiming for a velocity around 2250fps. When I tested, the recorded velocity was 1834fps the initial impact into the first jug looked good, but energy transfer dropped off real fast. I looked for the slug but no dice. The bullet deflected up into the 2nd jug and bounced off 3rd jug and couldn't be found. I thought I had the camera recording but in the bright sunlight I couldn't tell for sure and evidently I was wrong and I did not get the test recorded. :hmmmm:
006_zpsffcebb66.jpg
This example bismuth bullet weighs about 26 grains less than average weight in wheel weight alloy.
 
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good thread mt, cost wouldnt be to bad for a pocket full just for hunting after load development, but i for one wouldnt want to spend the rest of the day explaining it all to the game warden or judge, who would look at it and say (it looks like lead to me) prove it
 

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Discussion Starter #8 (Edited)
I did not understand why velocity was so low. Everything I could garner from that test just left me wondering.

That's when I contacted Rotometals and I did not get anything in response to help me.
I loaded two more, one over 15gr of Trailboss and the other with 45gr H4198. The Trailboss bullet recorded a velocity of 1406fps. That is what I was aiming for and I was happy for that, but the slug was lost again. This time, at 1400fps, the bullet escaped out the back of the 5th of 5 jugs that I had on table. The second test with 45gr H4198 recorded a velocity of 1046. The impact on hte jugs belied the velocity recorded and has led me to believe that the bullet is coming out of the barrel in more than one piece. The velocity is reading so low because it is measuring when the first piece crosses the first sensor and then when the last piece crosses the last sensor, therefor recording a much lower velocity.
On top of all that, my computer crashed when I was downloading the test footage and the footage was lost.
Next, I water dropped some and tested to see if it effected hardness and the answer is negative.
I have read some postings on the internet about other people's work with bismuth bullets and I have heard of people using as much as 20% tin in their bismuth alloy. I have concluded that I need to follow that direction and add tin to my alloy. I ordered tin from Rotometals and added enough to raise the tin percentage up to 15%. I dropped some bullets from that alloy this evening and it appears to have had little to no effect on the level of hardness. That was testing for hardness shortly after dropping them and tin takes a while to harden so the number may go up a little. Bottom line, forget what you learned about alloying with lead, this stuff is different.
I do not think hardness is the issue though. The bullet needs more tactile strength and that is what the higher level of tin should offer.
I will load some of the new, 15% tin alloy and test into jugs again soon.
 

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Discussion Starter #9
One more thing. The bismuth alloy melts at a lower temp and seems to have a propensity to smear. With that in mind, I lubed the bismuth bullets like a lead alloy bullet dipping them in LLA. Upon cleaning the bore after having fired three of these bismuth cast bullets, I see absolutely zero sign of bismuth in the bore.
 

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Hmmm, makes you want to cast up a few of those bismuth boolits and a whole bunch of LEAD boolits... That way you can hunt with the lead and if anyone asks, you can show them the bismuth boolits..... :flute:

Doc
 

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maybe pure tin or zinc would be cheaper, either way it will always look like lead to an untrained eye, maybe wardens will carry a test kit
 

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It may be far easier to change politicians (Common Sense ones) then make a reasonable bullets out of Bismuth!
 

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I sure hope California starts to change politicians after one of our anti 2nd state senators got caught for ...... wait for it.......... GUN RUNNING!!!! Leland Lee, a darling of the anti gun crowd with many awards from anti gun lobby was running guns with a known criminal and gang member... Maybe Ca. will vote in someone who has values like a Republican or.... ah who am I kidding? Its Ca so they like their corrupt anti gun morons.


Doc
 

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At temperatures about and above 710 degrees bismuth will vapor and combine with oxygen to form trioxide. A VERY corrosive vapor that will react with most any metals. Bismuth is not non toxic, just less toxic so Bismuth poisoning is possible, so be aware of flumes/vapors.
Bismuth is not malleable either so will need to regulate that with your alloy mix. Not sure if can quench bismuth, I know if its red hot it will react with water to form bismuth oxide (sort of like a rust).
Bismuth Melting point 520.7 F
Lead melting point 621.4 F
Bismuth Atomic weight 208.98
Lead Atomic weight 207.2
Bismuth Mohs Hardness 2.25
Lead Mohs Hardness 1.5
Bismuth density 9.78 g·cm[SUP]-3 [/SUP]
Lead density 11.32 g·cm[SUP]-3[/SUP]

 
Properties of some bismuth alloys
Alloy
Melting temp
bismuth
Lead
tin
indium
cadmium
Cerrolow117
117F
44.7%
22.6%
8.3%
19.1%
5.3%
Cerrolow136
136F
49%
18%
12%
21%
Fields metal
144F
32.5%
-----
16.5%
51%
Woods metal
158F
50%
26.7%
13.3%
10%
Cerrosafe
165F
42.5%
37.7%
11.3%
8.5%
Rose metal
208F
50%
25%
25%

 
 

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Discussion Starter #15 (Edited)
I sure hope California starts to change politicians after one of our anti 2nd state senators got caught for ...... wait for it.......... GUN RUNNING!!!! Leland Lee, a darling of the anti gun crowd with many awards from anti gun lobby was running guns with a known criminal and gang member... Maybe Ca. will vote in someone who has values like a Republican or.... ah who am I kidding? Its Ca so they like their corrupt anti gun morons.
Doc
I did hear about your gun hating senator. That story should have been huge nationally, but was stuffed in a closet real quick like.

I am withdrawing the political rant as not to distract from the intent of this thread. Sorry.
 

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Discussion Starter #17 (Edited)
I added enough tin to raise the percentage to about 15%. I water quenched and air cooled and I have been testing periodically to determine if the alloy hardens slowly. From all I can gather, water quenching has no effect on alloy's hardness compared to air cooling. It appears that the the bhn has been increased slightly with increase in tin. My estimation is the hardness went from about 13.5bhn with 7% tin to 14.3bhn with 15% tin.
I do not think that measuring hardness is that relevant with bismuth as it is with lead. At a molecular level, bismuth forms a staircase-like form of crystalline structure. Under high forces, bismuth shatters along those lines. What an alloy needs to achieve, is to prevent that fracturing nature of bismuth.
An interesting detail about the toxic level of bismuth. It is the active ingredient Pepto-Bismol.
It is said that the fumes from melting bismuth alloy can be toxic and therefor same precautions must be adhered to in regards to moving air and not breathing the fumes.
At this point, I am going to load some bullets and test into jugs to see how it performs with 15% tin. I suspect I am on my way to 20% tin, but I'll test a little along the way.
 

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Thanks for the update, sounds like you are moving forward still !! Positive airflow venting your work area regardless of what may be working with is always a good thing. Toxins are a funny thing, is amazing in what some super nasty things are used. But its all about concentration levels, some toxins that are deadly at even parts per thousand become beneficial at parts per millions or perhaps parts per tens of millions.
 

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Discussion Starter #19
I still have not captured one of these bismuth bullets after 4 tests. Anyways I learned some and I am going to keep on keeping on.:driver:

 

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Sounds like you are still moving forward with results !! Will be nice to see what results you have once the ratio is fine tuned !
 
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