I had a very interesting experience with my 4 inch 500 S&W Mag. with some reloads I built up and fired off at the range today. The load was 350 gr. Sierra JHP on top of 40 gr. of H110 with a Fed. 210 LR primers. The loading data given was 39 gr. as low and 43 gr. as a max of H110.

Outside temp was about 70 degrees and clear - I was shooting with a glove and wearing a tee-shirt & jeans, double ear protection and shooting glasses - When I pulled the trigger I felt a immediate flash of heat across my forearms and forehead. I fired the same rounds again and the same results - Then I had friend of mine shoot the same load, he said the same thing - "I could feel the flash of heat as it was like a gasoline flash over". Anyone else experience this heat flash before with H110 and the 500 S&W? It sure gets your attention, plus everyone around you

I have never noticed any heat coming off my 4" gun.  I usually shoot 45gr of H110 behind a Speer 325gr, or 30gr of H110 behind a 625gr cast bullet.  The 325gr loads don't recoil too bad, but when you light off a 625, it's brutal.  I have never seen anyone fire more than 5 before giving up with that shit.

That is definately not normal and I hope you do not blow up your gun. I too always shoot this bad boy with padded leather gloves. I never felt any heat with the reloads I use or the factory Corbon.

I have seen slow motion videos of these being shot and there is a nice flame. but I guess my eye is never quick enough or does not have the right angle to see it while I am shooting it.

I never have to shoot more than a few rounds, not because I get tired of it, but rather because I use it on watermelons and after the first (or sometimes 2nd) round, there is nothing left!

FlameRed - No I don't want my gun to blow up either - One factor maybe old powder? The can of  H110 is about 10 years old- Thinking about - I will dispose of it - better to be safe then sorry, though the cases did not seem to be tight nor primers flatten out.