Am I correct in my alloying plan for Pedersoli Sharps replica rifle cast bullets?

[JimGnitecki]

. . .
I think you are plowing new ground with coated bullets and smokeless, it is going to take shooting.

Yes, I agree. I will be conservative and safe and experiment in small increments.

Jim G

 

[JimGnitecki]

Oops! I overshot the (Brinell) target!



Recall that I planned to alloy 5.4 lb of what appears to be Lyman Alloy No. 2 (BHN = 14.7), with 5 lb of Hornady swaged bullets (unknown BHN but known to be basically pure lead) that did not shoot well in my CAS firearms, to create what I calculated to be a BHN = 12.5 alloy suitable for my Pedersoli buffalo rifle cast bullet shooting.

Looks like swaged those Hornady bullets are even softer than people think! I tested the alloy I blended today using the above formula, and at about 1.5 hours after casting a test billet, the Lee Hardness Tester shows a .075” indent which indicates BHN = 9 ! A second test 20 minutes later confirmed the result. I will need to blend in some more of the Lyman No.2 to increase the hardness!

I will try doing that tomorrow!

Jim G

 

[AJC1]

Oops! I overshot the (Brinell) target!


View attachment 1164049
Recall that I planned to alloy 5.4 lb of what appears to be Lyman Alloy No. 2 (BHN = 14.7), with 5 lb of Hornady swaged bullets (unknown BHN but known to be basically pure lead) that did not shoot well in my CAS firearms, to create what I calculated to be a BHN = 12.5 alloy suitable for my Pedersoli buffalo rifle cast bullet shooting.

Looks like swaged those Hornady bullets are even softer than people think! I tested the alloy I blended today using the above formula, and at about 1.5 hours after casting a test billet, the Lee Hardness Tester shows a .075” indent which indicates BHN = 9 ! A second test 20 minutes later confirmed the result. I will need to blend in some more of the Lyman No.2 to increase the hardness!

I will try doing that tomorrow!

Jim G

Do the same test water quenched and see what happens. I bet your at least 1bhn harder and 10 would be fine for your current test....

 

[gwpercle]

I actually have a Lyman Mag 25, so 25 lb capacity. I will heed the advice to start with a LOT more than the 4.6 lb I had initially thought. My reason for planning the low weight was in case I messed up on my bledning ratio, I wanted to have enough of the Lyman Lead left over unblended to try again. But if I need more wieght in the pot to ensure a consistent flow out of the valve, I'll drop that idea and go much heavier on my first session.

Jim G

Start with a full pot ... you can't have too much alloy hot and at casting temp.
Once your metal and moulds are heated up and you get to casting them ... you don't want to run out of metal ... when things are hot ...cast all the bullets you can ... you will find defective ones , so you need more than you think ... Those large bullets will deplete 25 lbs. quickly ... don't stop casting to inspect bullets , cast when metal / mould are hot as many as you can ...when cool then inspect bullets and cull the rejects .
Gary
Casting since 1967

 

[JimGnitecki]

Start with a full pot ... you can't have too much alloy hot and at casting temp.
Once your metal and moulds are heated up and you get to casting them ... you don't want to run out of metal ... when things are hot ...cast all the bullets you can ... you will find defective ones , so you need more than you think ... Those large bullets will deplete 25 lbs. quickly ... don't stop casting to inspect bullets , cast when metal / mould are hot as many as you can ...when cool then inspect bullets and cull the rejects .
Gary
Casting since 1967

I know you are correct, but I have an inherent limitation: I have a very limited supply of lead until my buddy delievrs about 50 lb of Linotype to me in Mid August. I hadonly 13.5 lb total of Lyman No.2, plus 27 lb of the swaged Hornady 158g bullets which my firearms intensely disliked.

To make the 10.4 lb of BHN = 9 alloy, I used 5.4 lb of the 13.5 lb of Lyman No. 2 alloy, which is the ONLY supply of alloy that I can use to HARDEN the 10.4 lb of alloy already blended.

So, I don't want to try to fill the furnace at this point, because then I have (a) no more room to further add more alloy to harden what I ahve already allowed, and (b) no ROOM in the furnace to add more Lyman No.2 if the furnace is already full.

So, I need to keep the total volume allowed smaller than what you (correctly) suggested.

Jim G

 

[JimGnitecki]

Do the same test water quenched and see what happens. I bet your at least 1bhn harder and 10 would be fine for your current test....

I assume you are saying I need to remelt the 10.4 lb of alloy, and this time, when dropping it out of the Lyman ingot mold, drop it into water, versus onto a metal surface? But if I do that, I may as well instead add some more Lyman No.2 to the mix to harden it instead of doing the water quenching. I dislike the idea of putting hot lead into cold water , as a safety issue.

Jim G

 

[Blue68f100]

Check it in a couple of week and see if it age hardens?

 

[JimGnitecki]

Check it in a couple of week and see if it age hardens?

I know it will harden with time, but I don't want to wait 2 weeks. Better to re-alloy for a bit more initial hardness, and then let a bit more hardness develop over time. How much will a lead alloy harden within a few days if not consumed before that?

Jim G

 

[AJC1]

I know it will harden with time, but I don't want to wait 2 weeks. Better to re-alloy for a bit more initial hardness, and then let a bit more hardness develop over time. How much will a lead alloy harden within a few days if not consumed before that?

Jim

The water quenching brings the alloy immediately up to full hardness. There is zero saftey concerns of any kind so I don't know how to address that with mitigating factors. I do exactly the same thing with an entire tray of bullets out of the powdercoat oven. My recommendation was a thing I learned after trying to size bullets the next day and add gas checks ruining the entire batch. Your alloy is harder than you measured and you can wait weeks, spend a bunch more money on adding more antimony or water quench.... with the volume I shoot I can't afford more expensive alloy and who wants to wait a month!!!!

 

[JimGnitecki]

The water quenching brings the alloy immediately up to full hardness. There is zero saftey concerns of any kind so I don't know how to address that with mitigating factors. I do exactly the same thing with an entire tray of bullets out of the powdercoat oven. My recommendation was a thing I learned after trying to size bullets the next day and add gas checks ruining the entire batch. Your alloy is harder than you measured and you can wait weeks, spend a bunch more money on adding more antimony or water quench.... with the volume I shoot I can't afford more expensive alloy and who wants to wait a month!!!!

Based on what you have said, I am going to look into how slowly or how quickly, and how much, a Lead alloy hardens with time.

Jim G

 

[JimGnitecki]

Ok, I found a posting in a Shiloh forum which I am reproducing exactly as it was posted there:

"
the book is cast bullets by col e h harrison a publication by the national rifle assosiation.. c0py right 1979. reprinted from past articles of the american rifleman.. i think col e h harrison was the question and answer guy back then.. (these books have some really amazing stuff... )

question: it seems to me that cast bullets become harder upon standing, please explain.........

col harrison replies. your observasion is correct. lead alloys do harden considerbly for a time after casting (spontanious hardneing is ment here not that from heat treatment. ). this has had almost no mention in the cast bullet information and the misinformation published to handloaders for generations. it is remarkable that something which can greatly affect bullet performance. and which is observable and measurable with simple means., has been over looked so long.. the pracitcal considerations are extent of hardening which is 50% or more, and the time during which it takes effect. these are brought out in the foll0wing brinell harness meadurments made by the preceedure alread published in the american rifleman, on a bullet aloy at three day inetervals after casting... o means the day of casting.. o days+ brinell 13...3 days=brinell 14.5,,,6 days 15.5....9 days brinell 20,, ...12 days brinell 19....15 days brinnell 20.....18 days brinnell 19.5........ thus the alowy reached nearly its full hardness by the ninth day after casting, though it will continue to harden further very slowly for some time longer.. ... this takes pace in softer alloys also. these measurment were made on another bullet alloy at four day intervals after casting... 4 days 9.5,,,,,8 DYS BRINEELLL 10, 12 days brinell 12.5.........16 days BRINELL 13,,,, 20 days brinell 16... . the increase then nearly stopped. the meal thus reached almost full hardness by the 20th day. this may be a more usual time than the nine days of the other alloy. ..............
"

On another forum site discussion on Lead alloys hardening with age, I saw:

"
The wheelweights I work with (modern ones) air cool to about 8 and age in a fairly linear fashion to 12 in 7 days and then end up about 13 in a few weeks. If I add 2% tin to make 2.5/2.5 it ends up approaching 15.
"

So, evidently, the hardening over a 2 or 3 week period can be pretty significant. For shooters using either cast or jacketed bullets at mid or high pressure loads, this is likely not a problem, as they prefer harder bullets to ensure no barrel leading. But for someone running low pressure cast bullet loads, and looking for better obturation, this appears to eb a significant issue. Another unexpected variable to try to control . . .

Jim G

 

[JimGnitecki]

Ok, I just did another hardness test with the Lee Tester. Recall that yesterday, shortly after the ingot was cast, the BHN was 9. This morning, At 21 hours after the ingot was cast, the Tester says the BHN is now already 11 (.068" indentation). I guess it's true that a Lead bullet alloy does start out right after casting as softer than it will ultimately end up at. I will do more tests on this sample ingot as time since casting it accumulates.

Jim G

 

[JimGnitecki]

The hardening of the alloy ingot to 11 already has me thinking that I should be able to cast it into bullets and it will be hard enough by the time I actually use the bullets. I assume melting it again for casting will “set the clock back” and it will again start at BHN = 9 (?).

Jim G

 

[AJC1]

The hardening of the alloy ingot to 11 already has me thinking that I should be able to cast it into bullets and it will be hard enough by the time I actually use the bullets. I assume melting it again for casting will “set the clock back” and it will again start at BHN = 9 (?).

Jim G

Yes any time you melt the lead your back to minimum hardness. If you castvup a large supply, and pull from old stock to load its not that big of deal. Working the lead by sizing also softenes it.

 

[MEHavey]

For the rifle, cartridge, pressures, and velocities he intends, he neither needs ...nor wants... additional hardness.
Shoot it.

 

[Jim Watson]

I think lead hardness will be of less importance after bullets are powder coated.

 

[JimGnitecki]

Yes any time you melt the lead your back to minimum hardness. If you castvup a large supply, and pull from old stock to load its not that big of deal. Working the lead by sizing also softenes it.

The softening via sizing is very interesting, because I will be powder coating the bullets cast from this alloy, which will add likely, what, .002" or .003" to total diameter (since the powder coating THICKNESS has to be doubled when considering bullet DIAMETER, as it adds maybe .001" to .0015" all the way around). I don't know yet what raw diameter the bullets will be as they drop out of the mold, but after powder coating, I plan to size half of them to .459" and the other half to .460". The Pedersoli rifle they will be fired in has a gunsmith-measured groove diameter of .4563". So, I will be trying both .0027" and .0037" larger than the groove diameter. With a reasonably soft bullet, even the .0037" SHOULD be ok, and obturation should be reliable.

Interestingly, the Lee sizing kit has been demonstarted to be capable of sizing down by even over .010" !!

Jim G

 

[AJC1]

The softening via sizing is very interesting, because I will be powder coating the bullets cast from this alloy, which will add likely, what, .002" or .003" to total diameter (since the powder coating THICKNESS has to be doubled when considering bullet DIAMETER, as it adds maybe .001" to .0015" all the way around). I don't know yet what raw diameter the bullets will be as they drop out of the mold, but after powder coating, I plan to size half of them to .459" and the other half to .460". The Pedersoli rifle they will be fired in has a gunsmith-measured groove diameter of .4563". So, I will be trying both .0027" and .0037" larger than the groove diameter. With a reasonably soft bullet, even the .0037" SHOULD be ok, and obturation should be reliable.

Interestingly, the Lee sizing kit has been demonstarted to be capable of sizing down by even over .010" !!

Jim G

Large movement in bullet diameter is undesired. .002 to .004 is fine and any little problems in roundness are also corrected. Large amounts of sizing turn into extrusion and major dimensions of the bullet start changing. This will lead to other issues I'm still studying like stability, cg and cr problems. BWS can probably explain in a lot more detail the effect and severity of each one.

 

[reddog81]

Sizing down .01 might be possible but the lube grooves will be wiped out and you’ll have large flashing hanging off the base of the bullet. Definitely not ideal if going for good accuracy.

 

[JimGnitecki]

Sizing down .01 might be possible but the lube grooves will be wiped out and you’ll have large flashing hanging off the base of the bullet. Definitely not ideal if going for good accuracy.

Yes, I am not planning any large scale resizings! The example I saw videoed was for a bullet being massively resized to a smaller caliber for which commercial bullets were apparently not available. I THINK that after that guy did his resizing, he lubed the bullets then, probably via pan-coating, as I don't recall seeing lube grooves in the bullet being resized.

Jim G