I was able to do a little reloading today with the 90 gr and 80 gr Sierras. I tried RE 15 and CFE223 powders. Both bullets measured COAL of 2.310" in my chamber. I suppose the difference in length of the bullets must be in the straight .224 part of the bullet. I only tried loading toward the upper Max load data listed on the Sierra website, thinking the biggest advantage of this round was being able to push long bullets at high velocity. My barrel just didn't want to shoot the 90s, 2 1/2" groups at 100'. The holes appeared round in the paper, but wouldn't group well. I loaded the 80 gr HPBT Sierras at COAL of 2.275", 26.5 gr. of CFE223 powder using 400 CCI primers in Federal brass. I was getting an average of 2841 f.p.s. 8' from the muzzle. The factory American Eagle 75 gr load listed at 3000 f.p.s. at the muzzle on the box and 2981 f.p.s. 8' from the muzzle on my Ballistic app was measuring 2885 f.p.s. in my 20' barrel. I'm sure all the published data is with a 24" barrel. With this handload I was able to get several 7/8" 5 shot groups with this load. I was a little surprised at how bad the 90s shot in my 1 in 7" barrel. This looks like what I will probably shoot for a while. This was the listed Max Load with the 80 gr HPBT Sierra, but at .015" longer COAL, so I suppose in theory a little less than Max pressure. Primers showed a little flat, but they seated extremely easy on first reload as I think the federal Brass may be a little soft, along with the primer pockets. No real signs of over pressure. I guess that the 1 in 6.5" or better yet just go to a 1 in6" twist barrel would be the best way to go.
Your Mileage May Vary, Chuck.
