And 1Fg compared with the reference velocity of 1400 fps, 1134 fps doesn't even come close
Oh well, a learning experience with this caliber.  Even the 4198 charge at 1310 fps doesn't come close to the stated 1510 fps

Quote:
Dales, good information. Why?
Alliant 300-MP burn rate is right in there with IMR/H 4227/4198 and a little slower than H110. So using 15.7gr of 4198, I'll drop down 10% and work my way up to where the rifle likes good accuracy
Thanks
As for the cork wad - on or off the powder column?

4227 is working good so far for me. Of the pistol powders mentioned, it seems generally more stable in reduced capacity loads and light bullets. Probably due to having more bulk, better fill, and generally takes a bit more powder to reach the same velocity.

4198 has a better fill, but leaves more unburned powder behind.

If your velocity is that much lower than a reliable prediction, I would capture a bullet and look for excessive carbon fouling in front of the base. Look for the same behind the neck of your brass. The pressure has to be going somewhere.

Also check the volume of the brass. My UMC depending on trim length, hold 38-39 grains of distilled water by weight. They are a bit short for the most part.

If using Quickload for estimates, I always have trouble with cast bullets matching predictions without making adjustments, and one of its shortcomings (or mine because I can’t figre it out) is that it does not recognize the pressure increase when you jam a bullet in the lands. It will allow for a negative seating depth, 1/16” in front of the case is input as -0.0625”. But pressure and velocity drop in the program, when measured velocity actually increases.

For what it’s worth, I’m using 12.6 grains of 4227 with a 135 Hoch bullet seated .080” ahead of the case. Velocity is in the low/mid 1500’s. I am sorting through some rifle and sight issues, as well as casting, but in general three shot groups are 3/4” at 50 yards. Tang sight, off bags. Load development really hasn’t even started other than picking a likely powder.

I wish you the best of luck on the primers. At least in this neck of the woods zero. Maybe somewhere on line, but then have to deal with good old Haz Matt!!!

Just to be a bit contrary; has any one tried two part  assembled cases?
Brass tubing plus machined base,  solder together with medium strength silver solder.
Might work well for those long narrow low pressure cases. Or course, this would need to be tested with appropriate safety precautions. 

Many years ago there was a lot of European made .308 brass that had smaller than normal flash holes and gave significantly better SD's.  Just a comment.

Wondering out loud about powders. Maybe H110 on the fast end and 1680 on the other.
There have been comments about 1680 giving nasty muzzle blast so it may be too  slow.

I shot a 28-30 at Coors in 1983, where ?? showed and told me about making cases from 30-06. Not easy, but he said he did it.