simple Hi-Tek coating

[Lakehouse2012]

Jumping back into the thread again after about 100 pages. Failed the smash test for the first time yesterday. I've overcoated boolits while I was learning and increased their diameter by .008", and they still passed the smash. My most recent batch is the best one I've ever done as far as looks go, actually followed the directions this time, thought I was golden. Whacked three of them with a hammer, got this all three times



Where did I go wrong? This is getting frustrating.

10 grams of powder, 1.75oz of acetone, 100 boolits at a time, plenty of dry time, 390 degrees for 9 minutes.

Id try more heat and not worry about color until you know they work.

Sent from my SM-G920V using Tapatalk

[Ausglock]

Did you smash after the first coat?
I really like to pre-heat the tray of bullets that is next into the oven by pacing on top of the oven. makes me 110% sure they are "dry" before baking.

[Grmps]

Possible causes:
1. Dirty alloy?
2. First coat to thick (old coating gets thick in the container, add more solvent) and use less coating, 1 mil to less than 1 pound of boolits on the first coating
3. First coat may not be completely dry (high humidity can cause this)
4. Oven temperature not right (try taking the temp up to 400* and confirm with an oven thermometer on the shelf your baking on


Like Trevor, I like to dry the freshly coated boolits at least 10 min on a wire rack in front of a fan then set them on a spacer on top of the oven for another 10 min to be 110% sure they are dry before baking (they will be warm to the touch)

You can't dry them to much

[DerekP Houston]

If the first coat is too thick, subsequent coats will *not* fix it. If you think the bullets got contaminated with oil a quick acetone bath with the next batch will cure that. I would mix up a fresh batch of solvent + powder and try recoating. Mine is slightly thinner than the recommended but I've found it easier to do 3 light coats.

[ThaDoubleJ]

Being that I've passed the wipe and smash tests every time, I actually forgot about smashing until I was all done, and forgot about wiping until I got on the thread and was reading through (still haven't wiped).
Edit: Wiped, slight discoloration of a paper towel with acetone, like nearly invisible.


As for dry, I live in Colorado, it's semi arid, the day was low humidity, and it was about 75 degrees. Each batch had about 15 minutes to dry in a nice breeze after coats, and I got no bubbling during cooking.

Dirty alloy occurred to me, but I use a bottom pour, and I smashed three bullets from different molds and different hours of my casting the day before, so I'm pretty sure the issue lies in my coating procedure.

Fresh batch of coating, I had mixed the last batch way too thin and it took my 7 coats to get .001" of coating, so I dumped that mix and did a re-do. I also ran three different batches of 100 boolits each, every one of them got slightly different amounts of coating, from "maybe too thick" to "that's way too thin" and got the same smash result with each.

Oven has a separate thermometer inside, on the tray, a tick over 400 degrees when empty, holding almost dead on at 390 after the door was opened and a tray of boolits put in.

It was recommended to me by a local caster that I try MEK vs acetone due to the humidity levels here, I guess MEK evaporates slightly slower. I need to get a can on my next trip to the store, could it be something that simple? I also gave that guy an entire tub of Old Gold, as I couldn't get it to work, thinking maybe this sparkly green would work better, but..... He said the Old Gold worked fine for him, so I'm obviously the problem.

[Grmps]

Don't get frustrated, it's something simple and we just need to figure out what.

If you are mixing it 20 to 100 you can go 20 to 120 for better adhesion

Some put a heat retentive media in the bottom of their oven to help the oven recover faster after the door has been opened. I use ceramic BBQ briquettes, some use firebrick and other pieces of metal.

100 boolits is a small batch, with small batches you need to be doubly sure as to the amt of the coating to the weight of lead. A nerd could probably explain this better than I can. when you coat, s certain amount of coating will get dispersed in/on the coating container. you run to small a quantity the dispersion rate changes. I like to run 8 pound loads (7 mil to 8 pounds first coat) and have had good luck with 5 pound loads (4+ mill to 5 pounds)

How old is your acetone?

Many of the coatings need to be well agitated immediately before coating especially the metallics.

Making sure the coating is completely dry and warming the boolits really helps

this is the metal "spacer" I use on my oven to pre-warm the boolits usually 1 bake cycle (10 min)


Try adding a couple more minutes to your bake time. If the coating starts getting dark due to the longer bake time then you can back the time off a little. Dark boolits pass the tests and shoot just fine

another reason for smash failure is not baking hot enough long enough.

[Ausglock]

My tray on tube spacers

[Avenger442]

I always hate to be the lone voice of dissent here but, I don't think flaking off of the coating is not one of the signs of under cooking either with temperature or time. While I've never tried it I think I remember reading that you can smash a bullet right after drying and if properly coated will not flake. Wiping with solvent is the only test for under cured bullets that I know of. And to fail that test it will take it down to the lead. Don't worry too much about a little color on your rag. Joe or Trevor can correct me if I'm wrong.

I magnified ThaDoubleJ's image to see if I could get a better idea of what shape of flakes he is getting. Would have been nice to see one smashed on a white paper towel and the photo taken of that. And to see if I could tell if this looked like my too thick first coat flaking. I really couldn't tell. The first coat is the problem I think. Like most of you are saying it is either too thick, not completely dry (which by the way are two different conditions that can occur separate from each other or together) or there is some kind of contaminant on the lead. ThaDoubleJ's second post seems to eliminate most of those. The one thing that I see that can be tried is drying longer or warmer, again, what some of you including Trevor have suggested. It is what I would try first.

This reminded me. I shot some flaky bullets the other day in the .308. I'm not suggesting you do this because it can leave lead in your barrel. These were bullets that I found in my cabinet from about three years ago. They were coated without gas checks to see if I could shoot close full house loads without the gas check and Hi Tek. Didn't work. They had already been sized ounce after the first coat. I installed gas checks and resized them. I didn't smash them again but had separated them into groups by weight and taped the different groups together with masking tape and marked the tape with weight. When I started removing them from the tape to load I noticed some of the coating coming off on the tape of about ten percent of them down to the lead in small spots. Well I ran short of the number I wanted to load with the ones that didn't flake so I loaded some of the flaked bullets and shot them last. They still grouped well at about 1 1/2" five shots at 100 yards. And while I didn't clean the barrel didn't see any signs of leading. What does this tell me. Well they don't have to be perfect to shoot well. But we need to strive to make them perfect so they shoot perfect.

[Ausglock]

Yep. A higher temp or longer bake time will not fix a first coat that isn't completely "air dry" or is "too thick"

[slide]

Could you go to your buddy's house and coat and bake some of your bullets? Might learn some more as to what is going on.

[ThaDoubleJ]

Ok, as for acetone age, unknown. A decade wouldn't surprise me, I'm not even sure why I would have ever purchased acetone, but I have two cans of it. Maybe to clean paintbrushes.

I have a 340gr boolit in the bottom of the mix container, and I give about a ten second swirl before squirting as the metallic bits seem to settle as they sit, and I squirt while it's all still spinning.

I think I'll switch to MEK and then try a little more drying, and a little more baking, maybe closer to 375 degrees.

I was expanding case mouths today, and having trouble getting these boolits in them, they measure at .455. Unfortunately, I forgot to measure any prior to coating, so I've either slathered on .003" of coating, or the mould is dropping them fat. I measured a bunch though, and it's a two cavity mold, and they're all .455 or .4545, so I'd guess I might have slathered too much again, but I had a full hundred with almost no coating on them after the first coat, and they don't smash good either.

By the by, these are 230gr and 252gr 45s

I've 45/45/10'd all the 230s and sized them down to .452, gonna shoot them anyway, casting with a 2-hole takes too long to throw them back in the pot. I'll take all this advice under consideration and report back after my next attempt, thanks everyone.

Slide: You know, I probably could, never even crossed my mind. He's a guy from a jobsite I frequent, and we talk guns, and I bet if I brought up my troubles he might offer some help. If I can't get it to work with the above ideas, then maybe I'll give that a shot.

[MAGA]

Question about smash test pass/fail

I was doing the routine smash test a few minutes ago, I work second shift so I get off late and had one batch left to smash test. I didn't want to wake the neighborhood so I used a vise instead of a hammer.
When smashing the bullet no coating flaked off. I was examining the smashed bullet further and just happened to scrape it with my fingernail, I could make some coating come off of the already smashed bullet this way. It would not come of by smashing with a hammer itself though

Normal?

[Ausglock]

Question about smash test pass/fail

I was doing the routine smash test a few minutes ago, I work second shift so I get off late and had one batch left to smash test. I didn't want to wake the neighborhood so I used a vise instead of a hammer.
When smashing the bullet no coating flaked off. I was examining the smashed bullet further and just happened to scrape it with my fingernail, I could make some coating come off of the already smashed bullet this way. It would not come of by smashing with a hammer itself though

Normal?

Sort of?
A vice puts slow pressure on the bullet as it deforms.
A hammer has shock loading on the bullet. Just like firing them.
Once it is smashed, you should not be able to scratch any off.

[Ausglock]

Well... Spent the coin and had my STI Trubor 38 Super upgraded.
It was 4th hand when I bought it. Had done a lot of work and the chamber was very sloppy. Fired brass was badly expanded and had started to jam in the chamber. Sent it to A brilliant gunsmith here in OZ. Victor Precision in Brisbane.
He bead blasted and hardchromed the entire gun. Chambered and fitted a new STI TruBor barrel. Installed and tuned the Cylinder & slide trigger kit, and covered the grip in Carborundum for a slip free grip.
Below is before and after. Fired it today for the first time.
200 rounds of 38Super loaded with 125gn Conicals with 2 coats of Kryptonite green. Barrel was shiny clean and the comp was free of any sign of lead... This was from a Brand new, never fired barrel. This HITEK is bloody great stuff.

[Grmps]

Nice rehab. Bet your Smith is super busy. You never mentioned whether you actually hit the target or not

[benellinut]

Well... Spent the coin and had my STI Trubor 38 Super upgraded.
It was 4th hand when I bought it. Had done a lot of work and the chamber was very sloppy. Fired brass was badly expanded and had started to jam in the chamber. Sent it to A brilliant gunsmith here in OZ. Victor Precision in Brisbane.
He bead blasted and hardchromed the entire gun. Chambered and fitted a new STI TruBor barrel. Installed and tuned the Cylinder & slide trigger kit, and covered the grip in Carborundum for a slip free grip.
Below is before and after. Fired it today for the first time.
200 rounds of 38Super loaded with 125gn Conicals with 2 coats of Kryptonite green. Barrel was shiny clean and the comp was free of any sign of lead... This was from a Brand new, never fired barrel. This HITEK is bloody great stuff.

Nice! I love 1911's, I'd love to have an hour with that one! I use to shoot Bullseye matches, I have a dedicade 1911 .45 wadgun with an Ultra Dot that will shoot better then I can and another I started with Millet target sights. I tried my hand at action pistol with the later a couple times, what a hoot that was! I did better then I expected but I had to choose which game I was going to play, with family I didn't have time for both so I went with the winter Bullseye matches, had more time during winter. There were a couple guys who had Colt .38 Super's converted to shoot .38 Special, I always wanted one but there were not cheap to have built or buy used. If memory serves me right the Bullseye rules wouldn't allow the .38 Super, it would have been much less expensive to use a Super then convert one to Special. I was in my late 40's, climbing close to bumping up from Expert when I started having spine problems in my back and neck, pinched nerves in my neck developed a shake in my right arm I couldn't control and within a few months my groups opened up and scores plummeted, soon it became frustrating, the fun was gone and I gave it up. I miss it dearly but I'm fortunate to have plenty of plaques, metals and great memories, it was time to make room for the younger guys.

If your striving to always improve, push hard, as hard as you can, don't think you have all the time in the world because one day you won't. Push hard, have fun, shoot em up and keep em in the X ring!

[MAGA]

Ok one more question

I have been using a 1500W toaster oven in conjunction with an oven thermometer. I have been doing batches of up to a little over 4 lbs at a time

I'm finding some that fail the smash test, they will have small amounts of little small flakes come off ( what another member called dusting).

I saw where HI-Tek joe said bullets must reach 180 c for 3 minutes while in the oven

My problem is that even baking 12 minutes with the trays preheated on top of the oven the thermometer never reached 400F for 3 minutes.

So In order to bring the temp back up I would turn the oven way up to 500 and allow it to slowly return the internal temp to 400F ( I watched the whole time and did not let it exceed 400F on the thermometer)

So my question is should I just leave it set on 400F and just let it bake until I know that the bullets reach 400F via thermometer even if it takes 15-20 mins?

From reading through the thread it will not hurt to bake the bullets longer than 12 mins just don't exceed 400F correct?

I also plan on doing less bullets in a batch to help temp stabilize faster.

[Grmps]

set your oven thermometer to where the thermometer in the oven reads 400
put some kind of heat retaining material in the bottom of your oven to help the temperature return to 400 faster ( I use ceramic BBQ briquettes, others use firebrick, pieces of metal or ??)
Flakes/ bumpy coating is caused by coating/swirling to long 10-15 seconds then dump, it's OK to dump wet.
the first coat should be thinner lets than 1 mil to 1 pound
It is OK to over bake, all that will happen is the color will get darker. you could bake them till the color gets darker then back of a minute.
400 --410 so far as I know, not a big deal, wouldn't go over 410.
You could check goodwill or thrift stores of a better (convection oven) they can be had for 10 to 20 $

Really think you need a better oven

[Ausglock]

You are overloading your oven. Reduce your bullet load to 1/2 of what you are doing and try again.
Higher temp/longer time will only darken the colour, as stated by my acolyte above.

[HI-TEK]

I'm finding some that fail the smash test, they will have small amounts of little small flakes come off ( what another member called dusting). Flakes after baking is generally caused by application of too much coating with first coat, and not drying adequately. If in doubt about dryness, simply bake only a few to test to determine if the pass smash test after first coat.
If they fail smash test, dry more, even if warm air drying at about 45-50C, then re-test bake a few again as comparison.

I saw where HI-Tek joe said bullets must reach 180 c for 3 minutes while in the oven. That is correct. But coating must be totally dry, this is of paramount importance with first coat.

My problem is that even baking 12 minutes with the trays preheated on top of the oven the thermometer never reached 400F for 3 minutes. You may get away with smaller batches, as it is obvious that your oven is not up to the task for larger loads as is. Insulation on walls may help with heat losses.

From reading through the thread it will not hurt to bake the bullets longer than 12 mins just don't exceed 400F correct? No that is nor quite correct. You can bake theses coatings until they become black, and they will work OK. Extra heating is not what makes coating fail.

I also plan on doing less bullets in a batch to help temp stabilize faster.

Great idea, as from your description your oven is low in capacity.

My replies as per Red inclusions.
Hope that they are useful