Reloadingtips.com

 
 

 

Address
web@loansoftware.com

 

 
 



Test the assertion:

Tin is required to cast good bullets.



 

Experiment 110818-A

Setup:

I have heard for 50 years you can't cast good bullets without tin. Never cared to try it  'til now.  One test does not make a "Law of Nature",  but one fall out of a tree convinced me of the law of gravity.  I am convinced.

I melted 5 pounds of reclaimed bullet cores from an indoor range ( No cast bullets ) This stuff is very soft. Bullets measure about 8 BNH ( Lee scale ). I assume they have very little tin because they were swaged, not cast and the melt when stirred and scraped looks like pure lead.

I would not normally use this for casting without the addition of some linotype to get the BNH up to around 12.

I took a mold, known to be good, and started casting. I tried every trick known to me and every suggestion mentioned on several web sites and I never managed to get good bullets. They were 98% either wrinkled or unfilled driving bands or badly frosted. Maybe 2 in 100 came out smooth and well shaped.  

This was not a quickie test. I poured five pounds of bullet metal three times. That estimates to about 43x15 = 645 bullets.  I tried temperatures from 600 to 750 degrees. Note that it was the same 5 pounds of lead melted and re-melted three times. Nothing was varied except casting methods and temperatures.

I tried Bottom pour with mold in contact with the spout, 1/2" drop, 3/4" drop, 1" drop. Straight in the hole. Around the sides of the sprue hole. Tilting the mold. Casting hot and dropping the mold on the pad before the melt had hardened.  I tried the same variations with the ladle.

At this point I accepted that  that alloy was never going to cast good bullets so I added two ounces of tin ( to the exact same metal ). That makes it  2oz / 82oz = 2.4% tin in addition to whatever tin may or may not have already been there.

Immediately, first filling, ( The mold was already hot. ) the bullets came our perfectly smooth, and perfectly filled with nice flat driving bands with perfect square edges.

Bullet core bullets average weight:

No tin in alloy

Worst examples  162.9 gr with a +/- 3 grain variance

Best examples  163.1 grains with a .5 grain variance 

With tin in alloy ( 2.5% )

 Average 161.2 gr with .5 gr variance.

Lee Brinell Hardness Readings

No Tin With Tin
.080 .076
.084 .080
.084 .078
.082 .078
.084 .076
   
Avg Avg
.0828" .0776"
   
7.2 BNH 8.2 BNH
   

 

 

Photos:

ctrl+mouse wheel zooms photos.

Cast with no tin. Worst examples. Approximately 40% of total.
(Not including the really bad 50% that went immediately back into the pot.)

No tin

Cast with no tin. Best possible examples. ( Less than 10% of total.)

No tin

 

Cast with 2.5% tin. About 80% keepers.

With tin


 

 

 
 

home | products | about use-mail


 
 

Right 1
Right 2


Right 3