Powder residue on cases for 308 loads

klh8 · August 31, 2002, 12:45 PM

Well,I am scratching my head.Need some info from you experts out there.
Had 3 loads loaded for my 308 700 varmint special using the 125gr sierra spitzer bullet,using BLC(2)powder.
The 2 lower velocity loads(2800fps and 2900fps)had black powder residue on the rims (fairly heavy) and some on the body.
Now,the load for 3000fps,the cases looked normal aftering firing.They were pretty clean.
What is going on?
All loads grouped well.The 2900fps cut a 3 shot clover leaf with 1 flyer.No signs of high pressure.Primers looked ok and saw no evidence of the primers leaking.Extractions also were good on all loads.
Could it be head space?

Is this anything to worry about?
Thanks alot
Paul

swifter... · August 31, 2002, 01:12 PM

Paul,

It sounds like your rounds are not generating enough initial pressure to seal the chamber. Not a big deal or a problem.

Tom

HSMITH · August 31, 2002, 01:20 PM

It is possible that you have set the shoulder back too far if you full length resized these or of they were fired in a rifle with a shorter chamber. Even with mild loads it is uncommon, and should not happen again if you just neck size the brass before leading again.

Khornet · September 5, 2002, 06:01 AM

in '06 bolt guns and M1. The loads performed fine, tho. I think the cause is a delay in full expansion of the brass, allowing some gas to flow around it before it seals, as stated above.

August 31, 2002, 12:45 PM	#1
klh8 Senior Member Join Date: January 24, 2002 Location: WV Posts: 120	Powder residue on cases for 308 loads Well,I am scratching my head.Need some info from you experts out there. Had 3 loads loaded for my 308 700 varmint special using the 125gr sierra spitzer bullet,using BLC(2)powder. The 2 lower velocity loads(2800fps and 2900fps)had black powder residue on the rims (fairly heavy) and some on the body. Now,the load for 3000fps,the cases looked normal aftering firing.They were pretty clean. What is going on? All loads grouped well.The 2900fps cut a 3 shot clover leaf with 1 flyer.No signs of high pressure.Primers looked ok and saw no evidence of the primers leaking.Extractions also were good on all loads. Could it be head space? Is this anything to worry about? Thanks alot Paul

August 31, 2002, 01:12 PM	#2
swifter... Senior Member Join Date: March 16, 1999 Location: So. CA Mountains Posts: 540	Paul, It sounds like your rounds are not generating enough initial pressure to seal the chamber. Not a big deal or a problem. Tom __________________ There are damn few situations so screwed up that adding government to them will not make 'em worse... The best homeland security is an armed & informed citizenery! Molon Labe!

September 5, 2002, 06:01 AM	#4
Khornet Senior Member Join Date: December 11, 2001 Location: NH Posts: 585	I see this from time to time in '06 bolt guns and M1. The loads performed fine, tho. I think the cause is a delay in full expansion of the brass, allowing some gas to flow around it before it seals, as stated above. __________________ The M1 does MY talking!

August 31, 2002, 01:20 PM	#3
HSMITH Senior Member Join Date: June 21, 2002 Posts: 2,019	It is possible that you have set the shoulder back too far if you full length resized these or of they were fired in a rifle with a shorter chamber. Even with mild loads it is uncommon, and should not happen again if you just neck size the brass before leading again.