Thread: Casual

Originally Posted by Micky Duck

my old rifle had loose bore and longthroat...so loads had plenty of room to releave pressure before projectile enguaged rifling.....my reloads for it were at hot end of scale.....
also I partial length resized...so in effect the shoulder COULDVE been up to ????1mm longer than normal......
IF new rifle has tight chamber,they wouldnt fit in.....the case would be too long......and if short throated,a hot load could well become a bomb...nowhere for pressure to go....shorter throat=shorter pressure curve=lower pressure tolerance=lighter loading.......
if you take it to the extreme,look at how Roy Weatherby made his rifles chambers....big long lead into rifling so when primer goes off and powder starts to ignite the projectile starts moving forwards,in effect giving a bigger case...this I believe is the theory behing Remington Hypersonic shot shell loads too....1700fps Vs 1500 in others.
my good mate just around corner also owns a .270 the loads his rifle tolerates are 2-3grns BELOW book maximum before he starts getting pressure signs...my old girl was 2-3 ABOVE .
hope that makes sense.

Sound thinking Micky,
My experience has been that current production rifles have tighter chambers compared with those of 30 plus years ago especially in sporting cartridges. One .308 I worked with chambered some factory loads tight. Your partially sized cases would be very unlikely to chamber in the new rifle. This is quite apart from the load likely being too hot. 30 years of use likely provided the long throat and reduced pressure. Something I would be interested to know is the make and model of both your old rifle and the replacement. Just curious.
Regards Grandpamac.