Well, I've been working my tail off for the last couple months with very little, if any, time off. It is 5 months later on this post and I'm able to add a little "real world" experience regarding these two powders. My 454SM barrel showed up from MGM and I finally got a couple hours to play with it and after the barrel break in process I began to do a little load development. This is what I got so far;
T/C Encore barrel by MGM 14" long chambered in 445 Super Mag.
Barrel break in began with Starline 445SM brass, Federal 155M primer and 250 gr. Sierra TM bullets over 27 gr. of Alliant 2400 powder. This produced some very nice velocities and good 100 yrd. groups, but very dirty. I shot this load only for the required MGM barrel break in process and to get my Leupold DPP on target. The average velocity over 40 rounds was 1789 fps.
Next I moved on to finding my hunting load. This load is going to be based around a 315 gr. WLN-GS LBT hardcast bullet from Montana Bullet Works propelled by AA1680 and VV N-120 powders, again in Starline brass with Fed 155M primer. I'm looking for a load not to exceed a muzzle velocity of 1550 to 1650 fps. being it a cast bullet. I loaded several charge weights of each powder in half grain increments and shot them for 5-shot strings. The AA1680 powder is very fine and would meter very well if one chooses to throw charges. The VV N-120 is like a mini stick powder and would work in a powder charger, but I don't think it would be smooth. Personally, for accuracy loads I choose to measure out each charge myself. . .yes, down to 1/10 gr.
The AA1680 loads began at 31.5 grs. and went up to 33.5 grs. At the 31.5 gr. mark my MV was a average of 1607 fps. with ES/SD of 38/15 and 2.5" 100 yrd. group. I stopped at the 33 gr. mark with a average of 1722 fps. with ES/SD of 19/9 still holding 2.5" groups. Primers looked good and no other signs of excessive pressure, just a hotter load than what I needed. I feel that the 32 gr. mark is were I would be using this powder.
The VV N-120 laods began at 30 grs. and went up to 32.5 grs. For 30 grs. my average MV was 1628 fps. with ES/SD of 17/8 with 2.5" group. I stopped at 32 grs. with a MV average of 1747 fps. with ES/SD of 28/13 and a 3.5" group. At 32 grs. primers showed signs of pressure, but still a shooter load. . .a screamer really! 30.5 grs. was a load that was worth looking into; MV average of 1667 fps. and ES/SD of 12/4 with a 5-shot group all inside a 2" Sticky-Dot. . .Yes, something to experiment with more for sure! ! !
Based on just this little bit of range time with the two powders, all though they are pretty close in performance, at this point I'm leaning towards the VV N-120. Uses a little less powder for higher muzzle velocities and a lower ES/SD spread. It does cost a little more, but it may be worth it. When time permits I'll be back out and run some more loads and will report back.
The above data was shot in MY T/C Encore pistol and these loads functioned SAFELY in MY pistol. . .maybe not in YOURS. Since there is very little load data for the 445 Super Mag and the above powders, my findings are based from Dan Wesson pistol shooters and my own trial and error. Start lower than listed and work up to these charges - BE SAFE!!!
