something to consider is covering the elements with the crumb catcher that comes with the oven. that way, you're getting a radiant heat which is what is needed with hi tek. i've seen that the direct heat on the boolits can ''burn''' the color after less that the recommanded cooking time.
You sure you've got Zombie Green? They look like a good match for Bronze.
Where are you placing the tray in the oven? Do not put it too close to the heating element as too high a temp will cause the colour to darken. How sure are you that the temp is correct?
That's better....
Hooroo.
Regards, Trevor.
Australia
shanep
They look much better and closer to correct colour.
Finish seems a little granular, that is normally caused by over shake coating for too long.
Once you add coating mixture, shake coat quickly and for just long enough to use up coating, (10-15 seconds).
If coating becomes tacky, it will start to start sticking and produces such finish.
During drying and baking, these type of surfaces will not flow out smooth.
The other way a rough finish may occur is the coated alloy was just not quite baked long enough.
When re-coating an under cured coating, the solvent starts to dissolve/strip off previously under cured coating, and this will form a rough finish.
If this all is finally baked the coating can produce such a granular finish.
Next step is simply to size one or two, this will take off surface lumps and should leave a glassy finish without the body of the coating being removed.
Do not be concerned if you over bake, and if colour changes. The coating has been baked for days at 200C, it turns out Black but coating performs well.
I have been using IR thermometers (yes plural) to measure actual boolits. When the oven thermometers (yes,plural) read 200C,the bullets actually hit 220C. That must be because of direct heat.
I'm on my third oven now,the same is still happening. So I have adjusted to 190C. The latest big household oven has strong fans and there really is a cyclone in there. Still the bullets get hotter than the oven.
My converted Wall oven is set at 200Deg C. The bullets (after 71/2 minutes) are 204 Deg C as shot by an IR Therm.
The oven has a heating element around the internal fan and the over head element working. 2 trays. one on the bottom shelf and another on the middle shelf. If I use the top shelf, I get darkened bullets.
Hooroo.
Regards, Trevor.
Australia
Petander,
If your bullets are coming out hotter that oven temperature it may be due to cycling effect of thermostats.
Some thermostats are able to cycle plus or minus 50C. They turn on 50 below set temperature and turn off 50 above set temperature. Essentially this is supposedly averaging at 200C.
If your thermostat is working OK, if the heating elements are not directly fanned to remove heat from them, than I suspect infra Red heat may be causing over heating of the metal.
It is not logical that oven air is at 200C but bullets are hotter.
If it is not the thermostat losing control, then it must be Infra Red energy causing over heating.
Hi, I have a question. I have used HI TEC for 9mm,40 and 45acp with great results. I just starting casting 165 gr 7mm bullets with a gas check design. Can I,Should I use the gas check after coating the bullets or forget the gas check. Thanks!
I coat 145 gr RCBS SIL and 160 gr SAECO for the 7x57. 2 coats of HITEK, check with actone rub and smash test , then seat GC and size.
HTH
"...Some days its rocket science, and some days it just zinc..."
rcslotcar
That is a great question. There are many variables. First, what alloy are you using?
Second, what velocity are you expecting to achieve?
Gas checks are normally used to prevent Gas cutting of Lead especially with hot powders.
Coating before or after gas check will work.
Can you supply more details please.
i'm using coww's with a very little tin added, brindle hardness around 19-20. Powder I've been using for Sierra 168gr bt hp is 68 gr of Hodgon 4831sc. This has been my max load from my Remington 700 which is very accurate. I was thinking to load down to about 60-63 gr for cast coated bullets maybe around 2500-2600fps. Again I haven't shot any cast 7mm yet, just trying to get knowledge before I put components together. I haven't shot "any" cast bullets thru my rifles (223-270-308-338win).
Last edited by rcslotcar; 10-03-2018 at 02:40 AM.
I would try with and without gas checks just to see how each perform, There are a few variables as others have said but velocity nearly always plays a part. I use gas checks on all my rifle loads except for my 357 max Martini which will not shoot as well with checks and prefers plain base. I would check that the checks fit after coating and fit them after coating especially if you use Aluminium checks as the coating does not stick well them but sticks well to copper. Regards Stephen
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |