15 February 2010, 03:13
HaggisAnother pressure question...
Fellas,
I have a question about pressure... ( I can hear the groans )
I use 45 grains of N160 behind a 140gr SMK in 6.5x55 at 3.1" COL for long range work (1000 yds). This has proved very accurate and I've been happy with it till now. The vast majority of my brass is Privi Partizan which has a total volume of 58.29 grains of water on avg. I knocked up an extra 10 rds of the same load using remington brass which runs to 59.4 grains water.
Right. The Privi brass didn't show any signs of extreme pressure but the remmy brass was knackered. Headstamps swaged, primers falling out, the classic signs of way too much pressure.
My question is why should the remington react like that when it's got slightly more capacity than the privi?
Both are cut the same length (2.154") + both are once fired. Viht manual lists max load as 46.7 for this combo so I'm still away from that.
Any advice would be greatly appreciated
Cheers
15 February 2010, 05:31
ramrod340Well it would sound to me like soft brass. However QL calls those loads in either case in the 42,000 range.
15 February 2010, 08:47
45/70 Thumper+1, Soft brass...seems like brass from the decades past ( as far as domestic brass is concerned) is far tougher. No scientific prove to back it up with, more of a educated guess.
15 February 2010, 13:59
HaggisThanks lads.
Now all I need to do is identify which bag they came out of. Got 300 remington empties here....
15 February 2010, 18:01
ramrod340I was very surprised as to what QL called the pressure. If 42,000psi is correct hard to see it causing problems with expanded primer pockets etc.
15 February 2010, 18:50
Nordic2Some US brass have .473 casehead instead of .478
15 February 2010, 19:02
Ol` Joequote:
Originally posted by Nordic2:
Some US brass have .473 casehead instead of .478
Euro brass isn`t always proper sized either.
Norma
Federal
PMC
Winchester
15 February 2010, 23:39
Larry GibsonMy oh my, I wonder what "good ole tried and true CHE" would have to say about this
case? (Pun intended)
Larry Gibson