Re: 140 Gr Accubonds for STW
Cacey, there are several things to consider when loading a 7 Mag. First you did not say what you were hunting. I am a deer hunter and hunt in SC and Kansas. We shoot out to 600 yds here in SC and the shots are usually not that long in Kansas, typically 300-350 at best. I have been shooting IMR 4350 with the 140's (64-67g depending on the rifle and lot # of powder). With the 160's, many 7 mags will shoot 61.0g of IMR 4350 into a single ragged hole when loaded with a Rem case and a 9 1/2 primer. My family and I have killed many, many deer with the Sierra 160g BT SP, it is a really fine bullet. We have also killed a few deer with the 120g Nosler BT loaded with 72g of R#22, but the deer may travel 40 yards. I think that your move to the 120g Triple shocks is a world class move and I would love to hear your loads: keithcandler at msn dot com.
To answer your question, does the BC of the 160 catch up with the 140?. Well, it is about a push, but the 160 is not as flat shoot'en out to 500 by a long shot, but will blow in the wind just a little bit less not much. One thing that you have to remeber is that the RPM's go up as the velocity goes up, and that usually translates in the bullet jacket opening up and transfering energy to the animal better at faster velocities. The thing is, you have to try different combo's and really see for yourself what really works best, and of course shot placement is everything.
In the last 3 years, we have been shooting R#25 with the 154g Hornady SP, SST, and Interbond. The Rem's that we shoot we are getting 3200-3250 out of the 154's, start at 79.0g and work up looking for signs of pressure in your rifle. We found that the WLRM primer better than the 215 with the Rem case. Short case life with this load. The regular SP has taken 3 elk in the last 3 years, and many deer have been shot with the 154 SST in the 275-325 range, this is a fantastic bullet. We have yet to kill anything with the Interbond.
Hope this helps!