First of all does your 444 have ballard or microgroove rife lings?
The dogma states microgrooves will struggle stabilizing over 300 grains. I have a microgroove and shoot hornady 300 xtp, and some barnes original 300 grains. I have used h4895 and h 4198. I would look on gunbroker and fell into a bunch of ammo. I tried to pay under 1.25 a round. Go to marlin owners .com and you will find a great group of triple 4 aficionados. They know way more than me!
They have a thread on bullet performance, and lots of reloading recipies. I have not been able to find any speer bullets lately but the 290 grained ones were rated very high in performance.
Last edited by Angus1895; 02/13/14.
