what causes the extactor to mark the end of the case,no other signs of high pressure and only 2 out of 10 have these marks. slight shinny square marks
maybe oil in the barrel causing high pressure.
Last edited by tolley; 07-06-2010 at 09:10.
I'm having trouble imagining what you mean. Some pics would probably help explain it
at the top just after the 6
Ok, I see what you mean now. What did the primers look like? Either the pressure is on other high side, or something is causing the case to slip back fractionally when firing. Maybe some lube left on the outside of the case?
tolley. Superb photo, one for Muir I think. I see a lot of good close up photos on the forum. What kit have you used to get this photo? Thanks JCS
Measure the expansion ring just in front of the web on the case and compare them, the ones with the mark and the ones without the marks. I have a feeling you will find a measurable difference. Somwhere around 0.001"+ I am guessing that marked cases will be larger and if so it indicates higher pressure on those rounds.
If it does not measure bigger then you have some other issues like lube left on case, or something as simple as a softer bit of brass.
Last edited by Brithunter; 07-06-2010 at 18:33.
Originally Posted by jcampbellsmith
just nikon coolpix l3 on macro.
That is from either excessive pressure or very soft brass. Whether the pressure is caused by oil in the chamber or too much powder, it is still pressure. Make sure your cases are trimmed properly and if so, try backing off the load 10 percent. ~Muir
yes there is a very little differents.
Originally Posted by Brithunter
im using lapua
brass lengh 2151
og bullet lengh touching rifling 2619
back off to 2609 og lengh
neck size only
Last edited by tolley; 07-06-2010 at 15:34.