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Texas10
06-29-2015, 01:04 PM
I just got a box of 75g A-Max and would like a good starting point for a load work up. I see your target is marked 77 Nosler, did you have similar luck with the 75's?

I load to 1.940 base to Ogive. I'm guessing you load to 1.892 with a .016 jump. Have you tried other jumps?

I'm going to shoot 600 yds for the first time tomorrow but won't have time to work up a load of 75's at 100 yds before going. I'll be shooting 69g Nosler CC's.

GaCop
06-29-2015, 05:25 PM
Sierra 77 grain Match Kings over 24 grains of Varget in RP brass and Fed 205M primers shoot 5 rounds into 1.060" at 300 yards for me in a Savage factory barrel, 24", 1 in 9 twist. I'm seating the SMKs .005" OTL.

Newbe
06-29-2015, 05:27 PM
I just got a box of 75g A-Max and would like a good starting point for a load work up. I see your target is marked 77 Nosler, did you have similar luck with the 75's?

I load to 1.940 base to Ogive. I'm guessing you load to 1.892 with a .016 jump. Have you tried other jumps?

I'm going to shoot 600 yds for the first time tomorrow but won't have time to work up a load of 75's at 100 yds before going. I'll be shooting 69g Nosler CC's.

I have not tried other jumps. Perhaps down the road I will. I was so ecstatic with the 3-shot group at that particular load (22.4gr), that I did not want to change anything on it, although I did change the brass from the original load by switching from once fired, processed and primed 08' L.C. brass to Virgin 13' L.C. brass. I was limited in 08' quantities....

I AM anxious to see your results. What will you be shooting them out of?

I have not tried the 75gr A-max.

Newbe
06-29-2015, 05:29 PM
Sierra 77 grain Match Kings over 24 grains of Varget in RP brass and Fed 205M primers shoot 5 rounds into 1.060" at 300 yards for me in a Savage factory barrel, 24", 1 in 9 twist. I'm seating the SMKs .005" OTL.
****~! That's nice! 1/3 MOA at 300 is nothing to sneeze at!

I've got a ton of those bullets, but I thought the longer bearing surface would make them unstable. Might have to load some up and see what happens! Especially since I have a bunch of the TIPPED SMKs!! :thumb:

Newbe
06-29-2015, 05:33 PM
Speaking of the Tipped 77gr SMKs, I bet those SOBs would be supersonic to 1,000 yds at the speeds I'm getting with the Noslers! (2,735 fps)

Texas10
06-29-2015, 05:53 PM
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.

Newbe
06-29-2015, 06:11 PM
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.

Excellent! I'd love to hear/see your results! :thumb:

darkker
06-30-2015, 07:41 PM
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.

Newbe
07-01-2015, 12:48 PM
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.
Good to know.

mwells72774
07-04-2015, 08:41 AM
Here in NWA I'll +1 the 75gr hpbt hornady but I use 20gr 3031

Txhillbilly
07-06-2015, 07:55 PM
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.

Newbe
07-09-2015, 06:45 PM
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.

http://img.photobucket.com/albums/v671/2fun/IMG_0788.jpg

GaCop
07-11-2015, 11:31 AM
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.

icker96
07-12-2015, 12:12 PM
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.

Newbe
07-14-2015, 02:06 PM
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.

jerry shaw
07-18-2015, 11:16 AM
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.

Newbe
07-22-2015, 03:58 AM
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.

Thanks Jerry. I actually got a couple good groups from a more recent work up. The smallest 3-shot groups are around 1/4" @ 100 yds.
I'll need to proof them at 100 yds again, then push them out to 600 or so to see if they remain stable.:cool:

jerry shaw
07-22-2015, 09:00 AM
Thanks Jerry. I actually got a couple good groups from a more recent work up. The smallest 3-shot groups are around 1/4" @ 100 yds.
I'll need to proof them at 100 yds again, then push them out to 600 or so to see if they remain stable.:cool:

Thanks. I hope it works out well for you.