Antimony and BP Boolits?

[Muddy Creek Sam]

Howdy all,

For Black Powder Boolits, what percentage of Antimony is acceptable in the lead?

Sam :D

[Springfield]

Less than is in Wheelweights.

[Muddy Creek Sam]

Springfield,

What about the alloy you just got from me? That is what I have the most of.

Sam :D

[montana_charlie]

I was just (yesterday) reading a post in which Dan Theodore was talking about a hard-for-BPCR alloy. It is intended to be hard enough to prevent nose slump on long ogive bullets, but still soft enough to perfprm as expected for BPCR shooting...especially with paper patched bullets. He calls it the 'three to seven alloy'.

It consists of three parts of Lyman #2 and seven parts of pure lead. The content works out to be 97% lead, 1.5% tin, and 1.5% antimony. The density (speaking about bullet weight) closely resembles 30-1 alloy.
According to Dan's hardness tests, it has a BHN of 8.2 when cast, but stabilizes at 9.8 after only 18 hours.

Dan's hardness numbers, for the softer alloys used in BPCR, are substantially smaller than the numbers found in the 'published tables' that you find everywhere. He believes they contain 'derivitave data' that was wrong when first published...but has never been changed because it has always been assumed to be correct.
You should look at his BHN numbers with that understanding in mind...

CM

[Muddy Creek Sam]

CM,

The Alloy I have is 95-2.5-2.5, guess I need to mis in some Pure. BHN is 10.5.

Sam :D

[Springfield]

The 97 1.5 1.5 sounds like what I try to have. My LBT hardness tester says it is about 9-10 Brinell. I have added more tin before but haven't found it helped fillout any as long as I kept the moulds hot, so I stopped wasteing it.

[Jon K]

Sam,

Unless you're using long nose pp boolits like DT, why do you want to use antimonial alloy for BP?
Also the boolits DT is using requires a fast twist to stabilize, because they're very long.

Why not just use a lead/tin alloy 1:20/1:25/1:30, keep it seperate from smokeless loads with antimonial alloy?

Make sense? or am I barking up the wrong tree?

Jon

[Springfield]

Because it's difficult to get the antimony out if you are using an alloy that came that way, like wheelweights or nuclear medicine containers.

[August]

I ain't as sophistictered as many o' these gent's, but I never found no use for antimony in boolits what I use in black powder shootin' irons. I cut wheel weights with pure lead for cowboy boolits, but them ain't as impotent what the long range gunz is. So, I use pure lead with enough tin in the mix to fill out the mold and no more for the long gunz.

That's what Iz been upta for the past couple years anywho.

[MT Chambers]

In my opinion antimony just causes BPCR bullets to be frosty, pure lead with a bit of tin(30-1) will not be frosty, but nice and shiny, as the good Lord intended.

[montana_charlie]

Unless you're using long nose pp boolits like DT, why do you want to use antimonial alloy for BP?

I ain't as sophistictered as many o' these gent's, but I never found no use for antimony in boolits what I use in black powder shootin' irons.

In my opinion antimony just causes BPCR bullets to be frosty, pure lead with a bit of tin(30-1) will not be frosty.
The reason DT (Dan Theodore) began working with antimonial alloys was to determine how stable they might be over time...not to look for harder bullets.

He spent a year doing his hardness tests at specific intervals, and tested a number of alloys...some with only tin, some with only antimony, and some with various amounts of both.
It appears that an alloy has good stability if the tin content and antimony content are equal.

His 'three-seven alloy' became stable at 9.8 BHN eighteen hours after casting, and remained stable for the entire year-long test.
I wish he had numbers to publish for a slightly softer alloy (perhaps 98/1/1) to use in place of 20-1.

You ask what the value of antimony is.
It is the ability to cast a bullet today and have it reach a known hardness in a short period of time (like tomorrow)...and have it stay at that hardness (essentially) forever.

That means you can load your 'match ammunition' during the winter, and expect it to perform consistently all the way through the following fall.

CM

[prs]

Wheel weight can cover a lot of ground regarding hardness. My WW PRS boolits will easily scratch with thumbnail, but I could treat them different and to get them harder than a (well no reason to go there). I like frosty boolits anyway and I let them cool real slow. If you want them as soft as possible, bring them up to just under slump in oven and then very slowly reduce the heat a few degrees every 10 to 15 minutes. It a PIA, but if you do a whole big bunch at once its not too bad. They do reharden a bit with age, but are still relativley soft.

prs

[Muddy Creek Sam]

prs,

I only have a couple of pounds of WW metal. I am using Isotope container lead.

Sam :D

[KCSO]

I had a long discussion with Doc Carlson about this and it's his opioion that NO antimony is best. He uses pure lead and tin only. Since I just hunt with mine and seldom over 300 yards I just cut wheel weights with pure lead. This is where Hydraulic needs to chime in...

[Wireman134]

I was just (yesterday) reading a post in which Dan Theodore was talking about a hard-for-BPCR alloy. It is intended to be hard enough to prevent nose slump on long ogive bullets, but still soft enough to perfprm as expected for BPCR shooting...especially with paper patched bullets. He calls it the 'three to seven alloy'.

It consists of three parts of Lyman #2 and seven parts of pure lead. The content works out to be 97% lead, 1.5% tin, and 1.5% antimony. The density (speaking about bullet weight) closely resembles 30-1 alloy.
According to Dan's hardness tests, it has a BHN of 8.2 when cast, but stabilizes at 9.8 after only 18 hours.

Dan's hardness numbers, for the softer alloys used in BPCR, are substantially smaller than the numbers found in the 'published tables' that you find everywhere. He believes they contain 'derivitave data' that was wrong when first published...but has never been changed because it has always been assumed to be correct.
You should look at his BHN numbers with that understanding in mind...

CM

Don't drop those boolits in water or yell have a BHN of 15 after 18 hrs., pardoner.

[montana_charlie]

Thanks for the tip, partner.
As a pardoner, I will pardon you for thinking I might ever do such a thing.

The closest I ever came to water dropping a bullet was when I shot a shark in the Gulf of Mexico.
CM

[runnin lead]

Didn't someone win last years Creedmore Nationals @ Raton last year shooting wheel weights ? Don't that same guy use wheelweights for shootin steel ?
He also uses Eagle Lube.

[Old Caster]

Out of about 30 BPCR shooters at Bench Rest Club in Missouri, I don't think a single one uses any antimony ever. You will get leading doing that and with Black Powder or Pyrodex it is the kiss of death if you don't get it all out. Those who "just had to try it" said it took several days of messing with the gun to get it all out and even then they were afraid there might still be some in there so several more days of cleaning to be sure. If some stays, and fouling will be under it, the barrel would be ruined. Even a day would make me nervous because the typical rifle cost 2K or more and they rust fast. Most use a 20-1 mix lead to tin but it varies all the way to 40 - 1 . Pure lead has been tried and they shot well but require such a high temperature to cast and are so susceptable to damage when loading it was given up. When any of these mixes are used leading is very limited and comes out easily.

[w30wcf]

I shoot repeating rifles with b.p. and my standard bullet alloy is w.w.+2% tin.
I have found they shoot as well as, and in some instances, better than lead/tin bullets. I have never had any leading issues.

w30wcf