Marking on cases

[basher]

HI ALL

REMI-243SPS

Whilst doing some load data using 95g berger vlds and vit n160.which shot very well at 100yrds.
After ejecting spent case on examination i noticed black marking down the full lenght of case.
I have tried to push head further in,still same,dropped powder and then they shot no good.
What is the reason for this? and how dangerous is it ?
Also i have varget and reloader 15 Does anyone have a load using these powders?

Regards Tony

PS twist in rifle is 1-9.25

[rewinder]

You don't say how much Vit160 your using. Sounds like not enough to seal the bore. The case expands to seal the bore when a cartridge goes off. If not enough powder is used it cannot do this. Gas and powder residue leaks back between the case and chamber walls. Lapua Reloading guide http://www.lapua.com/fileadmin/user_...deEdition8.pdf Another cause, not swabbing out solvent in chamber after cleaning or wiping off cases after FL sizing. Randy

[basher]

HI RANDY.

THANKS FOR THE REPLY.

Yes checked for clean chamber/cases
My load is 41gr of vit n160 which shot a 1 hole at 100yrd,which i am over the moon with.
Considering its a factory remi.
Have been told to push heads in and drop powder charge to no avail.
Cant seem to much info on the 95berger vlds using vit.
Should i up the load to seal cartridge,and by hjow much,
This does not happen with any other load so i can see where you coming from with this.

Thank you very much and hope to hear from you soon

Tony.

[rewinder]

Your near max already. Are the bullets moly coated. How many times have the cases been reloaded. Does this happen with the Bergers VLD's only. Could up the charge .3 grain at a time to find the true max load in that rifle,. Checking for brass protruding into the ejector hole, flattened primers, hard bolt lift, then back off a grain. Have you tried neck sizing or 3/4 FL sizing ,where you only size part way down the neck with the FLsizing die. Check your headspace, is it excessive when you resize. Randy

[basher]

Thanks randy.

Weather good today so i can get a few rounds off.
Will let you know the outcome.
Once again thankyou for this info.

Regards Tony