axmc 338lm pressure signs

[Norwegian musher]

shooting hand loaded 285 eld m's in my 338lm axmc 27" barrell 1:9.35 twist,getting 2800 fps,no pressure signs. but if i shoot hornady factory 285's i get 2870fps and ejectormarks even svipes..
same if i reload to same speed etc (93 grains n570,2870fps)
my friend's sako barrell shoots 2900 fps same lenght barell,but 1:10 twist and gets no pressure signs at all..

not worried about speed,my rifle shoots great but just curious; do the steeper twist in my rifle cause the pressure? same story with other axmc's vs sako' s around here

 

[Bacarrat]

What kind of brass are you using for hand loads? Factory Hornady brass is known to be very soft. I have even Hornady brass them stick in some 338LM chambers.

 

[Norwegian musher]

I use Lapua brass,fed 215 primers

 

[Norwegian musher]

i dont have a headspace gauge so i strip the bolt and size cases until the bolt closes easy but i cant move the bolt back and forth mutch so i believe i aint got too mutch headspace

 

[Dave62677]

I believe the barrel chambers is different between the factory AI and Sako. My buddy gave me few of his 338lm brass fired from his sako M10. I sized it and couldn’t chamber in my AI factory 338lm barrel. I did some measurements and it was the the lower half of the brass swell much more.

 

[Dave62677]

I would keep the 285eld at 2700ish. I did test the 255gr solid with RL26, it gives me 2950ish ES 12 at hot day. Work your load up for safety measures. I do see a velocity swing 30fps +/- with seating depth. I get 30fps less with .070 jump vs kissing the land