Anyone else had good results in a rifle with a powder that I haven't tried?

H4198
H335
IMR4198
Lil' Gun
RL7

My best so far seems to be H335, giving me 5 shots touching at 100 yards and about 2900 ft./sec. -- this from a 22 inch barrel, and before even playing with bullet seating depth...this is set at the standard 1.830" COL. What concerns me is that H335 is not an extreme powder, and I am a little worried about its temperature sensitivity...I am shooting in 35-45 degrees F now, and wondering if this will be a factor on the prairie dog fields at 85 degrees F...

With my .221 I started out using H4227 which worked quite well for 40 gr. bullets but it was noticeably slower than RL-7 which is what I use all the time. A buddy of mine uses AA 1680 and claims it will drive 40 's over 3400 in his carbine for what its worth.

Hmmm...actually, I have a pound of AA1680 to try, just haven't worked up any loads yet. Encouraging to know that it sounds like velocities are similar to that of Lil' Gun...I got about 3400+ ft./sec. with Lil'Gun and 40 gr. V-Maxes, but accuracy wasn't great...

AA1680 has been superb in my 221's, with 40gr Vmax and 40 Sierra hp's, and 3400fps is easily doable. Only LilGun has them going faster. I use 18.5gr, but AA says you can use up to 20.0 grains!
AA2200 is also a great powder in the Fireball, if you can still find some.
H322 also works well, and is a Hogdgon Extreme powder.
Great cartridge!
Try a search here and in small calibers for some previous posts.

Thanks for the posts...looks like it is high time to work up some loads with AA1680 and possibly H322.

One more question related to reloading in general...I noticed on the Accurate Arms site that they trimmed the cases to 1.380"...while I understand that fired cases expand and need to be trimmed back to spec, what is the reason for trimming below 1.400" (obviously talking about a Fireball case) -- it seems that this only would serve to decrease case capacity, granted, by a minute amount.

I don't trim mine shorter than 1.390" and one of the things I found with my .221 brass is that it "grew" a little the first two firings after that it just stopped growing.
You are correct a max load of RL 7 for a 40 gr. bullet damn near fills the case and some would fall out if the cases were even .010" shorter.