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gutpile
08-11-2013, 08:40 AM
I have some questions for the Hi-Tek users............Speed limit, is it the coating or the alloy you cast with the issue?
any one using it in rifles? gas check or plainbase? and if so how many coats? are you sizing before or after?
I read most are going with the powder coat.......I worry of the fillet and foil issue clean base is So VERY critical to accuracy. I do not mind spending the extra if Hi-Tek works better.

Thoughts

swheeler
08-11-2013, 10:00 AM
gutpile go to the SIMPLE HITEK COATING thread just above, leadman has been doing some rifle tests with it

Love Life
08-11-2013, 04:46 PM
It is both. You still need to match the alloy to the application, and some coating are supposed to be better with rifle. Leadman has the lead on rifle shooting right now, and I'll be running hard with the 8X57 soon.

Thompsoncustom
08-12-2013, 11:31 AM
Is there a alloy that can keep up with super high rifle velocity's like 3000fps?

leadman
08-12-2013, 05:47 PM
I have shot the 44gr Lyman round nose 22 cal boolit to 3,065 fps average with 1.8" groups at 100 yards. No leading. The 30-06 I have gotten a 314299 200grs Lyman up to 2,550fps but the accuracy was not what I wanted.
I have used Linotype which the 30-06 told me had exceeded the strength of the alloy at just over 2,400 fps. My last trials were with 50-50 COWW/lino heat treated to about 35 BHN. The coating process took it back down to arpound 15 BHN IIRC. It still shot the above load with the 223 Rem but the 30-06 did not do good at all. I had run out of IMR4350 for the 30-06 and tried WWII 4831.
I have cast some straight lino boolits and heat treated them yesterday. I am going to experiment with placing them in the oven at 375 degrees and checking after the first 10 minutes for BHN. Hopefully I can get it to keep the heat treated BHN for at least 2 coats of the Red Copper.
If not I will try 1 hour at 375 degrees and then water quench after coating to see what BHN I can gain back. I previously tried the normal heat treating temperature of 450 degrees but the coating turned very dark and chipped off when subjected to the hammer test.

It seems that the 22 cal boolits are less affected by shooting at a lower BHN than the 30 cal.
Richard Lee's Second Edition book has some very good information on the pressures different alloys can take. I think his figures are for boolits with no gas checks because I am able to shoot the gas checked boolits to a higher velocity before I notice the smoke from the barrel and the dramatic increase in group sizes.
I listed my 223 Rem loads in the sticky at the top of the page on Hi-Tek lube. I think I can go up at least 1 more grain in powder with no problems.
Do hope to get to the range later this week.

leadman
08-19-2013, 03:37 PM
Posted new shooting results in the sticky "simple Hi-Tek coating" at the top of the page.