fouled case necks

arrggg · April 24, 2005, 10:00 AM

hi, I'm reloading my .308 with 42gr of imr4064 and 168 sierra mk. My cases are all trimmed and neck sized. I am getting alot of fouling on the outside of the case necks after firing. I noticed a little of this ocuring with factory ammo but it is much worse with handloads, the fouling covers almost all of the case neck to the shoulder, does anyone have an idea of what is happening?

Wildalaska · April 24, 2005, 12:28 PM

How is accuracy? What velocity are you getting in terms of actual and predicted? What is OND after firing and then after neck sizing?

Wildnecksizes308Alaska

arrggg · April 24, 2005, 09:48 PM

accuracy is ok but it seems to be a little inconsistent (maybe its just me)
the necks measure .345 after firing and .336 after sizing.

cheygriz · April 24, 2005, 10:40 PM

In all likelihood, your load is not generqting enough pressure to expand the case neck tightly in the chamber and you're getting gas blow back. It probably isn't hurting anything, but increasing your powder charge could probably correct the problem.

I've had the same thing occur in target loads in the .30-06.

Ruger4570 · April 25, 2005, 07:49 AM

I tend to agree with cheygriz on the problem of not getting enough pressure to expand the necks,,, but,, you are within a couple of grains of a max charge of 4064 also. Therefore it does seem strange to some degree, your neck expansion isn't over the top, but is somewhat larger than my 308. I tend to get case mouth blackining mostly when I use boat tail bullets. I have assumed that the bullet releases and some of the gasses slip back past the boat tail before the case mouth has had time to fully expand. It really isnt a problem and will do no harm, just a little unsightly. I have seen many guns do this to some degree with no ill effect.

woodland · April 25, 2005, 08:18 AM

I have also noticed this with both my .308, and my 30-06. It is with factory ammo with mine. I haven't really shot a lot of hand loads in them yet.

Lennyjoe · April 25, 2005, 10:56 AM

I noticed that as well with my 30-06. I am using 59gr of IMR 4350. Accuracy is 1.5" @100yds out of an older Savage 110 model. Max load is 59gr with a 150gr bullet.

Wildalaska · April 25, 2005, 03:38 PM

I just had it with full legnth sized 6.5x55s fired in a big mil,itary chamber with a target (ie mil spec) load......

Shjoots good though

WildhungryneedburgernowAlaska

arrggg · April 25, 2005, 10:20 PM

ok. I was kinda worried that the gases might damage the chamber prematurely.

April 24, 2005, 10:00 AM	#1
arrggg Member Join Date: December 6, 2004 Posts: 22	fouled case necks hi, I'm reloading my .308 with 42gr of imr4064 and 168 sierra mk. My cases are all trimmed and neck sized. I am getting alot of fouling on the outside of the case necks after firing. I noticed a little of this ocuring with factory ammo but it is much worse with handloads, the fouling covers almost all of the case neck to the shoulder, does anyone have an idea of what is happening?

April 24, 2005, 10:40 PM	#4
cheygriz Senior Member Join Date: May 11, 2002 Location: high up in the rockies Posts: 2,289	In all likelihood, your load is not generqting enough pressure to expand the case neck tightly in the chamber and you're getting gas blow back. It probably isn't hurting anything, but increasing your powder charge could probably correct the problem. I've had the same thing occur in target loads in the .30-06. __________________ If you think a mighty military force is expensive, wait 'til you see what a weak one costs.

April 25, 2005, 08:18 AM	#6
woodland Senior Member Join Date: December 26, 2001 Location: western wa. Posts: 564	I have also noticed this with both my .308, and my 30-06. It is with factory ammo with mine. I haven't really shot a lot of hand loads in them yet. __________________ "There is no spoon..."

April 25, 2005, 10:56 AM	#7
Lennyjoe Senior Member Join Date: June 28, 2001 Location: Southwest Ohio Posts: 1,150	I noticed that as well with my 30-06. I am using 59gr of IMR 4350. Accuracy is 1.5" @100yds out of an older Savage 110 model. Max load is 59gr with a 150gr bullet. __________________ If you see a Military man or a Vet, stop him and say "Thanks".

April 24, 2005, 12:28 PM	#2
Wildalaska Junior member Join Date: November 25, 2002 Location: In my own little weird world in Anchorage, Alaska Posts: 14,172	How is accuracy? What velocity are you getting in terms of actual and predicted? What is OND after firing and then after neck sizing? Wildnecksizes308Alaska

April 24, 2005, 09:48 PM	#3
arrggg Member Join Date: December 6, 2004 Posts: 22	accuracy is ok but it seems to be a little inconsistent (maybe its just me) the necks measure .345 after firing and .336 after sizing.

April 25, 2005, 07:49 AM	#5
Ruger4570 Senior Member Join Date: April 3, 2005 Location: Rochester, New York Posts: 2,136	I tend to agree with cheygriz on the problem of not getting enough pressure to expand the necks,,, but,, you are within a couple of grains of a max charge of 4064 also. Therefore it does seem strange to some degree, your neck expansion isn't over the top, but is somewhat larger than my 308. I tend to get case mouth blackining mostly when I use boat tail bullets. I have assumed that the bullet releases and some of the gasses slip back past the boat tail before the case mouth has had time to fully expand. It really isnt a problem and will do no harm, just a little unsightly. I have seen many guns do this to some degree with no ill effect.

April 25, 2005, 03:38 PM	#8
Wildalaska Junior member Join Date: November 25, 2002 Location: In my own little weird world in Anchorage, Alaska Posts: 14,172	I just had it with full legnth sized 6.5x55s fired in a big mil,itary chamber with a target (ie mil spec) load...... Shjoots good though WildhungryneedburgernowAlaska

April 25, 2005, 10:20 PM	#9
arrggg Member Join Date: December 6, 2004 Posts: 22	ok. I was kinda worried that the gases might damage the chamber prematurely.