50/50+2% tin

[str8shot426]

The alloy I use the most. I only have my own experience to go on here, but I wanted to get some input.
My supply casts great looking filled out boolits, but the sprues break instead of shear off. My sprue freezes to a slightly frosty state after approximately 3 seconds.
Should I continue as stated, or is it intervention time?

[boho]

Sounds right to me with my limited experience. I don't water my WW that much. I use 7# WW to 4# pure/SOWW + tin. They work well in 9mm and 380. Change the time when you cut your sprue and see if you get a cleaner cut.

[DrCaveman]

With influence from goodsteel's consistency thread, i have been using a more strict cadence to my sprue cutting and boolit dropping

Been finding that when a sprue takes about 3-4 seconds to solidify, if i wait another 3-4 seconds before opening sprue plate, the base is cleaner. Then another 2-3 seconds before opening mould blocks and tapping. About 10-18 seconds between pours, with the other tiny delays figured in

My new favorite alloy is the same as you are using (pretty much)

Try waiting another few seconds before you cut the sprue, ill bet the mould stays hot and your bases will be better

Edit: these numbers are for 2-cavity lee moulds. Bigger ones will of course require a different count

[str8shot426]

I didn't specify. I am using a lee 2 cavity .30-170fn.

I will try slowing down. The sprue scrap seems almost brittle. When cooled the boolits are quite malleable.

[white eagle]

keep experimenting you will get the results you are after

[castalott]

I am wondering if your alloy is contaminated.... Doesn't sound like it is acting right...Dale

[10 ga]

Yeah, just a little slower and you will be OK. I usually run 2 or 3 molds at the same time. Cast, cast, ... sprue cut boolit dump, sprue cut boolit dump.... repeat.

Malleable is good! That is the mix I use for all my hunting boolits= saboted or PP for ML and "greased" or PP for CF rifle.

I "smelt" full converted propane pots of raw ore to get a good amount of any 1 kind of lead, like a pot of COWW, then a pot of battery terminals, then pot of SOWW, then pot of sheet lead, then cable sheathing etc... Label all my ingots and do whatever mix I need for boolits I'm casting. I do 95% of my boolits in the 1-1 + 2% alloy. I usually use pewter for the 2% so that isn't exact but gets close enough. You're on the right path. 10

[str8shot426]

Today's batch was better. Seems to be all heat and cadence related. My bottom poor and thermometer is on the way, that should help with some variables.
I am done with with the ladle, pot and fire!!

[Jeff Maney]

Today's batch was better. Seems to be all heat and cadence related. My bottom poor and thermometer is on the way, that should help with some variables.
I am done with with the ladle, pot and fire!!

You will not regret this upgrade! I have been using a bottom pour Lee pot for years. Added a PID controller last year, another great upgrade.

Jeff

[MBTcustom]

Today's batch was better. Seems to be all heat and cadence related. My bottom poor and thermometer is on the way, that should help with some variables.
I am done with with the ladle, pot and fire!!

You might want to check out this thread. I wrote it for person in your situation:
http://castboolits.gunloads.com/showthread.php?269912-Consistency-applied

[str8shot426]

You might want to check out this thread. I wrote it for person in your situation:
http://castboolits.gunloads.com/showthread.php?269912-Consistency-applied
This is a good read. Looking at what I am trying to accomplish and the tools presently used, I can compare it to building a bridge with a stick and a rock.
Upgrading my casting equipment should help remove some inconsistencies.

[Larry Gibson]

Also try adding the 2% tin to the COWWs by weight first and then mix that alloy at 50/50 with the lead. You'll get a better balance of antimony to tin forming the sub metal SbSn which then goes into solution much better in the lead of the COWWs. The additional 50% lead then mixes better into the solution. Over all it makes for a better alloy.

Larry Gibson

[Gray Fox]

Larry:

Not to hijack this thread, but are you mixing in 2% of the original 5# of WW or 2% of the final total of 10# combined weight? Thanks, GF.

[str8shot426]

I fired up my new lee 4-20. With some experimenting found 5 on the dial was perfect for my alloy. Kept a steady and consistent process and behold!, perfectly sheared and filled out bases.

No regrets on that purchase.

By the way, yep.....it drips.

[Larry Gibson]

Larry:

Not to hijack this thread, but are you mixing in 2% of the original 5# of WW or 2% of the final total of 10# combined weight? Thanks, GF.

What is wanted is to balance the % of antimony and tin. COWWs these days has, at best, 2.5 % antimony and, at best, .5% tin. Thus I add 2% tin of what the weight is of COWW. Doing so gives a good % of the sub-metal SbSn which by it's property then mixes in solution much better than antimony by itself. Once that is done that alloy can then be diluted down with pure lead in any % wanted while maintaining the correct balance of antimony and tin. Mixing COWWs and lead at 50/50 and then adding 2% tin of that total weight is adding 1% more tin than is needed or actually wanted as the you then have more tin than antimony in the alloy.

Larry Gibson