100 gr Amax range results for Howa HB and a question on the load results

[grayfox]

Went to the range today with some 100 gr Amax's laddered for 8208xbr, and my 6.5 Howa HB.
Got some decent results but it also raises a question in my mind.

Only the 25 yd range was open so no real pix, but data gathering was the primary goal anyway.
I loaded new Hornady brass, 100 gr Amax set at 2.240, cci450's, in sets of 4 each, 29.4, 29.6, 29.8, 30.0
Everything shot well and no pressure signs or sticky bolt lifts encountered. Using my Magnetospeed, indoors, 72 deg F, 328 elev give or take.

29.4: Avg 2687, sd=15
2682
2678
2710
2675

29.6: 2709 avg and sd=17
2691
2698
2726
2721

29.8: avg 2759 and sd=9
2762
2757
2770
2748

30.0: avg 2771 and sd=15
2787
2763
2754
2780

29.8 is the best velocity group with an sd of 9, but I do note a jump in the avg from 2709 (29.6) to 2759 (29.8), larger than any of the other deltas.

So, do you think 29.8 is too high? No over pressure signs, brass and primers looked fine. Bolt lift was fine. And the shot/recoil did not feel any different from the others. Don't think I want to go over the 30, but if 29.8 is a good load then I could see using it...

[s3silver]

With what you described it looks good to me. For comparison, most folks are right in the range of 28.5 gr 8208xbr for 123 gr projectiles. It looks like you went into the next ladder with the 29.8 charge, nothing wrong.

[xlcc]

I'm at 30. grs.of XBR with 100 AMAX in my Howa HB with fine accuracy,2.245'' COL.,Rem 7.5 primer going 2770 to 2780 fps.

[grayfox]

xl, any velocity readings for that 30.4?
The jump did give me cause to think, b/c in the 123 class bullets xbr seems to jump quickly past 28.5 into warning territory...
If this 29.8 turns out to be a good node it'll be a nice shooting load, 2760-ish is not too shabby.
I plan to do some more testing of it next range session.

[rabiddawg]

Reloading manual shows a load of 31 gr 8208 under 100 amazing running 2954 FPS.

I’m loading 30.8 of 8208 under 100 Nosler bt for three of my Grendel’s

[grayfox]

Appreciate all the comments, it's many times good to get a sanity check.
For my 18-er (AR) I have nodes at 29.3/2712 of the xbr for the Amax, 29.0/2640 for the Nosler 100 BT.
I'll see what the BT's do for the Howa after I settle these Amax's out.
I did see that 31 gr load in the Grendel Hbk vol 2, for an AR.

[xlcc]

xl, any velocity readings for that 30.4?
The jump did give me cause to think, b/c in the 123 class bullets xbr seems to jump quickly past 28.5 into warning territory...
If this 29.8 turns out to be a good node it'll be a nice shooting load, 2760-ish is not too shabby.
I plan to do some more testing of it next range session.

over 2800fps.see correction above.

[grayfox]

looks like 2760 might be the low end of this node... at least I know now that there's room above. This Howa is turning out to be a good shooter.
Thanks again!

[rabiddawg]

I too found a node for my rifles at 29.9 and 29.6. Hunted with them for two seasons. I also try to avoid max charges just to be careful.

Knowing I was leaving some speed on the table I decided to work up from 30 to 30.8 in .2 increments. I got lucky that Both my 20” guns liked 30.8 both under .5” 5 shot group at 100. I shot a three round group with one of my 16” and it was way better than any of the factory ammo groups so it’s gonna hunt with the new load too.