I was deburring some flash hole’s in some 257 wby mag brass

hardhit · February 5, 2009, 03:21 AM

Recently I was deburring some flash hole’s in some 257 wby mag brass an then uniforming the primer pocket when i inserted the flash hole tool I noticed quite some residue had built up in the hole, I was unaware that the flash hole had gotten quite small and wounded if this would affect ignition which in turn would affect accuracy what’s your thought’s as to the affect it may have?

IllinoisCoyoteHunter · February 5, 2009, 08:42 AM

Yes that would affect the ignition of the powder which could very well disrupt accuracy. I am no ballistician. but I would think that the semi-clogged flashole would not throroughly ignite the powder initially, creating a flatter initial pressure curve. I could be wrong.

kraigwy · February 5, 2009, 08:54 AM

It would be awful hard to tell with out testing to see what would happen.

I do know one thing for certain, if they are all clean, and uniform they will shoot better. I having done a lot of testing my self, but I feel certain, and comfortable saying that clean uniform flash wont make a gun shoot worse.

Consistancy is pretty important in the accuracy department.

Inspector3711 · February 5, 2009, 11:04 PM

One thing I found is that walnut media can get caught in the flash hole. When you deprime a case the pin on the die will force the piece of walnut shell into the flash hole. It will stay lodged in there except for the part that the pin made a hole in. A flashole deburring tool will scrape it out. It may or may not be the issue for you, but you don't want anything restricting the flash hole.

February 5, 2009, 03:21 AM	#1
hardhit Senior Member Join Date: August 18, 2008 Posts: 343	I was deburring some flash hole’s in some 257 wby mag brass Recently I was deburring some flash hole’s in some 257 wby mag brass an then uniforming the primer pocket when i inserted the flash hole tool I noticed quite some residue had built up in the hole, I was unaware that the flash hole had gotten quite small and wounded if this would affect ignition which in turn would affect accuracy what’s your thought’s as to the affect it may have? Last edited by hardhit; February 5, 2009 at 07:43 AM.

February 5, 2009, 08:42 AM	#2
IllinoisCoyoteHunter Senior Member Join Date: December 23, 2008 Location: Southern Illinois Posts: 1,527	Yes that would affect the ignition of the powder which could very well disrupt accuracy. I am no ballistician. but I would think that the semi-clogged flashole would not throroughly ignite the powder initially, creating a flatter initial pressure curve. I could be wrong. __________________ ~~IllinoisCoyoteHunter~~ ~NRA LIFE MEMBER~ ~NRA CERTIFIED INSTRUCTOR~

February 5, 2009, 08:54 AM	#3
kraigwy Senior Member Join Date: June 16, 2008 Location: Wyoming Posts: 11,061	It would be awful hard to tell with out testing to see what would happen. I do know one thing for certain, if they are all clean, and uniform they will shoot better. I having done a lot of testing my self, but I feel certain, and comfortable saying that clean uniform flash wont make a gun shoot worse. Consistancy is pretty important in the accuracy department. __________________ Kraig Stuart CPT USAR Ret USAMU Sniper School Distinguished Rifle Badge 1071

February 5, 2009, 11:04 PM	#4
Inspector3711 Senior Member Join Date: February 9, 2008 Location: Puget Sound Washington Posts: 1,553	One thing I found is that walnut media can get caught in the flash hole. When you deprime a case the pin on the die will force the piece of walnut shell into the flash hole. It will stay lodged in there except for the part that the pin made a hole in. A flashole deburring tool will scrape it out. It may or may not be the issue for you, but you don't want anything restricting the flash hole. __________________ "If someone has a gun and is trying to kill you, it would be reasonable to shoot back with your own gun." The Dalai Llama (5/15/01, The Seattle Times) "That rifle on the wall of the labourer's cottage or working class flat is the symbol of democracy. It is our job to see that it stays there." George Orwell