Hi-Tek Coating vs. Lubed Cast Reload Data?

[BigBoreReloader]

Just curious about the group's thoughts on this... To date, I have reloaded mostly jacketed and lubed cast boolits, but I am considering using some Hi-Tek coated projectiles for my 44 mag and 500 mag loads. Are you able to just use cast load data or do you need to adjust for the coating?

[Larry Gibson]

Not 44 mag or 500 mag but I conducted an extensive test of four different HT coatings on a 230 gr Lee TC bullet in 45 ACP and 45 Colt. Several different firearms were used bot rifle and handgun. I also pressure tested (Oehler M43 with Contender test barrels) the loads which were identical (all loaded at the same time). I found there was essentially no difference between the HT covered bullets and the same bullet with just traditional lube (BAC). The velocities were basically the same as were the pressures.

The HT treatment neither reduced velocity nor reduced the psi.

I have found the same with other PC and HT covered bullets of various calibers tested in rifles and handguns.

[BigBoreReloader]

Not 44 mag or 500 mag but I conducted an extensive test of four different HT coatings on a 230 gr Lee TC bullet in 45 ACP and 45 Colt. Several different firearms were used bot rifle and handgun. I also pressure tested (Oehler M43 with Contender test barrels) the loads which were identical (all loaded at the same time). I found there was essentially no difference between the HT covered bullets and the same bullet with just traditional lube (BAC). The velocities were basically the same as were the pressures.

The HT treatment neither reduced velocity nor reduced the psi.

I have found the same with other PC and HT covered bullets of various calibers tested in rifles and handguns.

Thank you, Larry... that was extremely helpful. I appreciate the education!

[mdi]

I have always started with cast bullet data for my PCed, commercial PCed and commercial Hi-Tek coatings. During a load work up I watch for problems; fouling, tumbling or sticky extraction, etc. (and change or new component I do another work up starting with book starting data).

[kayala]

I PC my bullets but I had to throw my PC-d 700 grainers for 500Mag back into the pot - nose become too fat to fit into cylinder, so for that mold I'm planning to go to traditional lubing.

[BigBoreReloader]

Thanks... have not gotten to the 700 grainers yet... just 535 and below so far. But I aspire to!

[wmitty]

Larry; thanks for posting this information. I’m sure there are many here who have wondered about the effects of coatings on boolits in regards to pressures and velocities.