What else ?
I have just reloaded and shot my first ammo - 9.3x62, Nosler AB 250gr, N140, 20" barrel
I followed the book etc and started low (51gr) and worked up, but ran out of linear velocity gains at 55gr (2310fps) v's 57max (2355fps). The grouping and velocity variation also declined badly after 55gr - no sign of pressure at 57gr.
Was hoping to get to 2450fps ?
Any suggestions ?
You're done unless you switch powders. As you noticed, you ran out of any real velocity gain after 55 grains so it's time to look for a different fuel. I am curious though: If MAX charge listed at 2355 fps, why would you hope for 2450?? What rifle are you shooting??~Muir
PS later that evening: I took a look at Hodgdon's site just for yucks, and found that only one powder -H4895- will deliver that speed with a 250 grain bullet in the 9,3x62; and that by only 30 fps. This includes IMR powders and Winchester Powders. You might be chasing the unachievable. I have a great deal of interest in the 9.3's as I own a 9.3x57 and believe it to be not too far behind the 62mm version factory loads in a modern rifle. The 9.3 x62 and X57 are old cartridges that perhaps, like the 6,5x55 and other old cartridges, could be boosted by modern powders and rifles. The H4895 load was, however, at 48.5K pressures already.
Last edited by Muir; 22-06-2010 at 04:48.
To reach you goal of 2450fps use a lighter bullet like the 232 grn Norma.
Many thanks for your replies
What I meant re 2355fps at MAX was that was the max velocity I was getting over the chrony at MAX (57gr) load
The rifle is a new Mannlicher Pro H Mountain 20" barrel
Looks like I will just have to stick at 55gr/2300fps and maybe look to try a different powder and lighter bullets in the future
Is there anything significant to try/gain re bullet seating depth or amount of crimp ?
It's hard to say. Milking an additional 100 fps from crimp and seating depth (Unless carried to extremes) might be tough but you can try. A lighter bullet would be more sensible. You might want to try H4895 if you can find some: great powder and it will put you in the neighborhood you're looking for.
Originally Posted by qwerty2008
Nice rifle choice, BTW.~Muir
don't know where you are but i'm in shropshire. i'm sure i've got some 4895 upstairs hidden away. if you are nearby you can have it to try some loads with (i think there is about 1/4 of a tub.)
I have found that experimenting with the COL has given faster results than varying charges (in terms of accuracy); has anyone else found this?
Method has been to use the mag length as a useable max and the Min Col as the lower end...
Is it the short barrel that has given the limitaions here as well as the powder choice?
I am reloading with 250gr Nosler AB's, they have a crimp groove round them, which dictates COL ? - do I need to seat them to the depth of this groove or can it be ignored ? Loads of space in the mag. My reloaded rounds are 81.9mm COL and I think max would be 83.6mm
Yes I have: exactly the way you do it, too. It's a pretty accepted practice on this side of the pond. Good work!~Muir
Originally Posted by Milligan