Newby,
I will be shooting a Model 12 BVSS in .223. 26 in varmint barrel, 1/9 twist.
I was incorrect about the bullet being an A-Max. It's a 75 g Hornaday Match BTHP. I"ll see if I can load some up tonight and give it a go tomorrow.
Remember that air become important in this discussion. As stability is about RPM, which is a function of BOTH twist and velocity. The 75gr Amax is much longer than the 77gr class bullets. So while the 77's are good down low where I am, for me the 75's have to be pushed over-pressure to get the required velocity; again in my results. Now go up in altitude, or have a faster twist, and the discussion changes. It is perfectly normal for a mfg to be off by 1/2-twist, from stated. And as always barrel smoothness will play a bit part in this.
I'm a firm believer in the theory that if it bleeds, I can kill it.
Here in NWA I'll +1 the 75gr hpbt hornady but I use 20gr 3031
My model 12 1-9 twist shoots the 75 gr BTHP's excellent,but the longer 75 gr AMax's prefer a 1-8 twist barrel. They shoot great out of my 1-8 twist AR's.
I just loaded up some of the new 77 gr Sierra tipped Match Kings to try out as well.
Should be interesting to see if these will stabilize as well seeing as how they are supposedly a little longer than the Noslers concerning the bearing surface.
I've tried the 69gr TMK in my 223AI (1/8" twist) 26" heavy varmint barrel and short action 223 Rem with a varmint weight, 9 twist factory barrel at 24". I've been testing all my handloads at 300 yards lately and so far, the best grouping in the 223 Rem is 1.43" for 5 shots and velocity at 2739 fps. The Ackley has done a bit better with velocity pushing the 69 grain TMK to 2953 fps and grouping into 1.6" at 300 yards.
I have shot 75r AMAX out of a Savage Model 11 with 1:9 twist 22" barrel over 22.8gr and 23.1gr XBR8208 with good results (both sub MOA). I bought and loaded them just out of curiosity to see if they would stabilize. However, I only have a 100 yard range, so I have not bothered to load anymore. I am saving them for when I get the chance to shoot 300yds or beyond. They just aren't worth the extra money for 100yds.
Well I got a couple of good groups with these, but they're too ****ed hot.
Loaded up another batch starting at the bottom load and working up to 1/2 of the max listed charge.
Also loaded up a batch of the tipped 69gr SMKs. Hope to try these out in the next week or two.
9 twist barrels, as noted above, work fine for heavier .224 bullets.
After lots of experimentation I found that 75-77 gr bthp match bullets with 24-24.5 grains of several good powders (including Varget, RE15, H4895, VV N140) does really well. After many thousands of rounds in testing and competition, I am not really excitable about which of the combinations is THE Best.
Most all of my bolt guns, and all of my space guns, will get a half MOA with nearly any of them.
Since I'm shooting at one MOA x-rings, I virtually never have to blame low scores on the ammo. Once I figured out that all the ammo shot better than I do, I quit wasting a lot of my time and spent more time in practice.
You will get slightly better performance with one or the other, depending on your barrel, but most of them will do quite well.
Just my two cents.
Good luck.
Bookmarks