Reloading for 77/44 - need experienced reloader help
Trying to work up a decent load, so far everything has been 3-4 inch groups (I can shoot much better than that) when within published loads. Tried multiple bullets, powders, and factory loads. Stock has been upgraded to a Boyd's, trigger to a Volquartzen.. everything is properly torqued, barrel is free floating, quality scope, barrel clean, and so on..
Currently trying to work a 270gr Speer Deep Curl with H110. I did find that there is a big jump to the lands (.085") even loaded at max magazine length (1.650"), jump to lands is .140" when loaded to published COAL.
Hodgdon is the ONLY resource I can find with 44 mag rifle data. Max load online is 21.5gr for that bullet with H110, giving a speed of around 1640fps.
At 21.5gr I'm only getting about 1550fps (via LabRadar), would like to get to 1640fps if possible. Been working up slowly above the 21.5gr/1550 published max load, and groups are getting better. Do not have ANY pressure sign yet. Last group was just a smidge over 2" at 1650fps at 75yds.. I can live with that speed/accuracy.. In case you're wondering, 5-shot StDev was about 20, and ES of 52, which isn't too horrible for a rifle like this, and certainly doesn't indicate pressure problems.
I'm wondering if I'm pushing the pressure limits of the 77/44 even though there are no signs on the brass? I'm quite a bit over 21.5gr...