10 August 2011, 21:25
Rae59338 WinMag rim and belt diameters?
Would some of you measure your rim and belt diameters on some new 338 WM brass and post it?
Not sure if I have some way undersized factory Winchester brass or way oversized factory chamber. My new brass is measuring .528 to.5285" as I recall. Lyman book shows .532" but I think that is outside spec.
I am shooting in Tikka T-3 rifle and getting some serious dimensional differences just ahead of the rim.
10 August 2011, 23:10
cgbachJust looked at some old .338 load data, fired cases, not new. Belts were .533, head in front of belt .516. I don't know what the o.d. tolerance is on the belt but in my experience it usually is a sloppy fit in a factory chamber. As long as you get proper head space I wouldn't think it would be a big deal.
C.G.B.
11 August 2011, 00:14
243winxbThe maximum SAAMI for a 338 win.mag.on the rim & belt is .532" It can be smaller by -.005" The maximum diameter in front of the belt is .5127" This can be smaller by -.008"
SAAMI drawing of cartridge & chamber here> PDF file-SAAMI Drawing Headspace on the shoulder, not the belt.