.357Mag Marlin: Unburned Powder After Firing

[Reloader222]

I use 16gr of IMR4227 with a Fed205 SR primer on a 158JHP bullet in my .357Mag Marlin Rifle (18" barrel) and still get unburned powder flakes in the barrel after firing. I use a reasonsable taper crimp. What else could be the problem?

 

[Kevin Thomas]

The "reasonable" taper crimp is probably part of the problem. Pick up one of Lee's Factory Crimp Dies, and lock that bullet in there, tight. You may also want to play with soem other primers and see if that helps, but I'd go straight to the crimp die first.

Not much of a Lee fan myself, but this is one tool that I have to say works better than anything else on the market.

 

[J E Custom]

The "reasonable" taper crimp is probably part of the problem. Pick up one of Lee's Factory Crimp Dies, and lock that bullet in there, tight. You may also want to play with soem other primers and see if that helps, but I'd go straight to the crimp die first.

Not much of a Lee fan myself, but this is one tool that I have to say works better than anything else on the market.

+1

That would be my best guess also.

Also some powders burn dirty and if the crimp doesn't fix it I would look at other powders.

J E CUSTOM

 

[boomtube]

"What else could be the problem? "

Low chamber pressure. If the pressure is low it's nearly impossible to burn all of a "slow" powder charge and 4227 is slow for handgun cartridges.

Try a faster powder, more powder, hotter primer, heavier bullet, harder crimp.

 

[Trickymissfit]

I use 16gr of IMR4227 with a Fed205 SR primer on a 158JHP bullet in my .357Mag Marlin Rifle (18" barrel) and still get unburned powder flakes in the barrel after firing. I use a reasonsable taper crimp. What else could be the problem?

try 14.5 grains of AA #9. Should give you about 1800fps
gary