Newb reloading question

[mcspecialed]

Hello,
First time poster, kind of new to reloading. My problem is that while shooting my reloads, I occasionally get unburned powder blown-back on my forehead and arms. I'm shooting 165 grain .40 rainier hp bullets, loads are on the lighter side (5.6 grains) with AA#5. I use the lee carbide dies and factory crimp die. Is the crimp too light? I would appreciate any help. thanks

 

[medalguy]

I don't have a .40 but it might be your loads are TOO light. Insufficient pressure does not seal around the brass and sometimes you can get blow-by of gas and unburned powder in your face.

 

[ArchAngelCD]

Like said above, your charge is way too low. Accurate's Load Data Site lists a starting charge of 6.5gr for a 165gr bullet in the 40 S&W. Your charge is very low and should be brought up to at least the starting charge because low pressure will cause unburnt powder as well as poor accuracy. The load range is 6.5gr to 7.2gr AA#5.

Welcome to the forum.

 

[zxcvbob]

If you want light loads, I recommend using a very fast-burning powder, like Red Dot.

 

[ArchAngelCD]

Fast powders don't usually work well in a high pressure short straight wall cartridge like the 40 S&W. That would work much better in the .45 Auto because it's a fairly low pressure cartridge.

 

[mcspecialed]

Thanks for the reply's. Rainier's website says that loads should be the same as for an equivalant weight lead bullet since rainier bullets are copper plated. I will definitely increase the charge a little and hopefully that will take care of the problem. Accurate powders data does not list a load for a lead 165 grain projectile. The closest one is 170 grain with a starting charge of 5.5 grains. I was thinking that bumping my charge to 6.1 (for 165 grain projectile) should be sufficient. thanks again

 

[ArchAngelCD]

Sorry, I missed the fact you were using Rainier bullets. You are correct, you should use lead bullet data instead of data for jacketed bullets. Loading 6.1gr should help a lot, please keep us posted on the results...

 

[918v]

You can use fast powders in the 40 if you want soft light target loads. I think his problem lies in too light of a powder charge and not enough case tension on the bullet which results in incomplete combustion. The Lee FCD often reduces case tension because the carbide ring is too tight and the bullet gets squeezed down inside the case. The case springs back a bit because it is harder, while the bullet does not because it is softer.

I'd forego the FCD and go for max case tension, minimum crimp, and a higher powder charge or a different powder alltogether.

 

[mcspecialed]

Thanks for the help guys. Increased the charge to 6.1 and went to the range today. Fired off 150 trouble free rounds. The problem appears to be resolved.

 

[zxcvbob]

Fast powders don't usually work well in a high pressure short straight wall cartridge like the 40 S&W.

Sure they do, they just max out with pitiful muzzle velocities. But if you are trying to develop a light load, you can get it and still have enough pressure for the powder to burn clean and consistent.