simple Hi-Tek coating

[AbitNutz]

So I've been reading and watching the videos about using low temp on powder coating so as not to soften the lead.

What is the situation regarding Hi-Tek? Am I losing hardness by repeated heating to 400 degrees for 8 to 12 minutes?

On the final heat I water dump them out of habit.

I typically use 3 coats and heat at 400 degrees for 10 minutes and then water drop them. I've never bothered to check the hardness because I've been fortunate enough to be able to use straight Linotype. Am I softening up my Linotype?

[Ausglock]

HITEK coated Alloy MUST, Must reach AT LEAST 185 Deg C!!!!! for AT LEAST 2 minutes for the coating to fully cure.
That is why I do 200Deg C for 7 1/2 minutes in the Wall oven and 12 minutes in the benchtop ovens.

[AbitNutz]

HITEK coated Alloy MUST, Must reach AT LEAST 185 Deg C!!!!! for AT LEAST 2 minutes for the coating to fully cure.
That is why I do 200Deg C for 7 1/2 minutes in the Wall oven and 12 minutes in the benchtop ovens.

I get that, and I'm not going to alter or play with those recommendations at all. It works too well. What I'm worried about is what that continued 400 degree heating and reheating does to the hardness of the lead. According to what I've read, it can drop the lead hardness by half. That's a problem, if it's true, and it doesn't come back through age hardening over time.

[Ausglock]

No problem with 2,6,92 alloy.

[AbitNutz]

Has anyone tested what the alloy hardness is before they cook the bullets compared to after? I may have to do that. It would be interesting to see what happens to my Linotype bullets after 3 coatings and 3 trips through the oven at 400 degrees for 10 minutes and then water dropped....and then what they are a week later.

Also, you mentioned 12 minutes in a benchtop oven and 8 minutes in a stove. I've only been doing 10 minutes on my benchtop and things seem to be fine. On your recomendation though, I'm going to move to 12 minutes on each cook. Is there a downside this? Can I over cook them?

[slide]

I use range scrap. That is all I can get and it is all I can afford. The testing was done with a cabine tree tester. After casting and before coating the bullets tested around 10 bhn. Water quench on the last bake and testing two days later the bhn was 12 to 15. Checked some yesterday that have been setting for about a month and are still holding at the 12 to 15 range. I don't know how your linotype will react. Lee makes a hardness tester that is around fifty bucks last I heard.

[ioon44]

Has anyone tested what the alloy hardness is before they cook the bullets compared to after? I may have to do that. It would be interesting to see what happens to my Linotype bullets after 3 coatings and 3 trips through the oven at 400 degrees for 10 minutes and then water dropped....and then what they are a week later.

Also, you mentioned 12 minutes in a benchtop oven and 8 minutes in a stove. I've only been doing 10 minutes on my benchtop and things seem to be fine. On your recomendation though, I'm going to move to 12 minutes on each cook. Is there a downside this? Can I over cook them?

Your Linotype bullets will return to the original hardness after a week or more just like it does after casting. In my experience you can get leading from Linotype if they are not sized to fit the bore, I consider Linotype too hard for bullets and I mix Linotype 50/50 with pure lead and makes about a 6-2-92 alloy.

There is no downside to over baking the coating it just makes the color darker and shoots fine, getting the first coat dry is the most important step.
I bake for 12 min at just over 400 deg F.

[Intel6]

Broke in two new .459" moulds in and got some bullets cast and coated.

The first one is a NOE mould that was designed to make bullets mainly for the .458 SOCOM but then a crimp groove was added so it could also be used in 45-70 rounds. As you can see it was also made just for coating as it has no lube grooves. I coated these in Bronze 500, added a gator gas check and sized them to .459" The final weight was right at 360 grs.



The second one is also a NOE mould that I got to cast heavy (500 gr.) bullets for subsonic loads in the .458 SOCOM but this could also be used in single shot 45-70 loads. This was also a coated bullet only mould and was coated with Bronze 500 and sized to .459"

[asmith80]

Has anyone tested what the alloy hardness is before they cook the bullets compared to after? I may have to do that. It would be interesting to see what happens to my Linotype bullets after 3 coatings and 3 trips through the oven at 400 degrees for 10 minutes and then water dropped....and then what they are a week later.

Also, you mentioned 12 minutes in a benchtop oven and 8 minutes in a stove. I've only been doing 10 minutes on my benchtop and things seem to be fine. On your recomendation though, I'm going to move to 12 minutes on each cook. Is there a downside this? Can I over cook them?

I did a little test before and after with hi Tek just for my own peace of mind. I was using COWW and air cooling. Before 1st coat of Hi-Tek they were coming in at 14.3 bhn with my Lee tester. After coating twice (the amount I normally do) they were coming in at 11bhn. After a week and a half of age hardening they were at 12.5 bhn. So it seems you lose some hardness initially, but you do regain some over time. 12.5 seems to be plenty hard for what I'm doing so I'm satisfied with the standard procedure for hi tek

[popper]

I posted this on another thread but I'll put it here too. Made an alloy with 0.8%Sb/0.5%Cu/1% Zn. Hitek'd coated 165 gr for 40sw - AC, just BLL on 185 gr GCd 30/30. Both worked fine, no WD needed. My normal poor levergun shooting. ~1800 fps. Top 2 are sierra jacketed.
Attachment 203623

[AbitNutz]

Yeah, that's what I was worried about. You lost 22% of your hardness immediately. It gained back 14% after a week. Those are significant loses on an alloy in the 10 to 15 bhn range.

I don't know if Linotype acts the same way but if it does, I'm talking about a water drop bhn of upwards of 25 or 26 and an ultimate hardness of about 22 bhn after a week. I guess that's not too bad. I'm hard pressed to think of something I can't do at a bhn of 22. 22 bhn is brutally hard lead.

Some reports I have seen are of 50% and are not recovering a significant amount after aging...Imagine starting out with 15 bhn and ending up with under 10. That would be a real problem.

[dikman]

Range scrap can vary a great deal in hardness. It depends on hw many .22 soft bullets get melted with the centrefire lead bullets.

True. I use a plastic garden sieve that I bought at Bunnings and find most of the .22 falls through the holes, just leaving .38/9mm.

[slide]

AbitNutz, sounds like you need to invest in a hardness tester. Then you will have a good idea of what is going on. It would be interesting to see how the linotype reacts.

[slide]

Okay guys, changing subject, If you need to continue with the hardness question won't bother me. This information may have already been found out by someone else and I really don't think it is worth much. My son and I did some chronograph testing with powder coated bullets and hi-tek coated bullets. This was a NOE 358429 hollowbase mold. Bullets around the 158 weight. Used 4.0 grains of unique powder. On average the hi-tek bullets were around 50 fps faster than the powder coat bullets. We were using a smith&wesson model 64 four inch barrel revolver. I though it was interesting. THIS IS NOT A MY COATING IS FASTER THAN YOUR COATING POST.

[dikman]

Hmm, PC crowd won't like that .

[asmith80]

I use range scrap. That is all I can get and it is all I can afford. The testing was done with a cabine tree tester. After casting and before coating the bullets tested around 10 bhn. Water quench on the last bake and testing two days later the bhn was 12 to 15. Checked some yesterday that have been setting for about a month and are still holding at the 12 to 15 range. I don't know how your linotype will react. Lee makes a hardness tester that is around fifty bucks last I heard.

So just to clarify, are you saying you WQ after about 10 minutes in a 400 degree oven? And you get that big of a hardness jump?

I didn't think 10 minutes would be long enough to really cause an effect on the hardness if quenched. I may have to try this out just for the sake of it

[popper]

Range scrap is pretty soft and MAY not WQ at all. Normal age hardening can increase BHN a couple points. My post 9130 shows you can add 0.5-1% Zn to range scrap that has a tad of Sb and get an alloy that doesn't need to be WQ. I added Zn to pure, it helped but not that much. This is the 40sw target, 2x HITek, 400F for 12 min. AC. Top shots are WWbox.
Attachment 203650

[benellinut]

Yeah, that's what I was worried about. You lost 22% of your hardness immediately. It gained back 14% after a week. Those are significant loses on an alloy in the 10 to 15 bhn range.

I don't know if Linotype acts the same way but if it does, I'm talking about a water drop bhn of upwards of 25 or 26 and an ultimate hardness of about 22 bhn after a week. I guess that's not too bad. I'm hard pressed to think of something I can't do at a bhn of 22. 22 bhn is brutally hard lead.

Some reports I have seen are of 50% and are not recovering a significant amount after aging...Imagine starting out with 15 bhn and ending up with under 10. That would be a real problem.

Just a thought, try baking some without any coating following the directions as if you were coating them and see what happens. I may be wrong and I'm sure the guys will correct me if I am but I can't believe the coating would have any impact on the hardness so it may be a test you could run and see what you get after baking? Am I off base guys?

[bfuller14]

AbitNutz,
Try to contact leadman on here.
He did some testing with linotype on here early on.( pg. 31 post 619)
Maybe he can help.

[dikman]

"Range scrap is pretty soft". I guess that's going to depend on the range itself where it comes from? If it's used by every man and his dog (public range?) then yeah, it could have anything in it. At the range where I collect mine as far as I know very few (if any) cast their own, it all appears to be commercial stuff. There is the odd bit of pure from muzzleloaders and a bit of .22, but when I'm melting 100+ kilos at a time that's pretty insignificant.