260 Rem & 123gr A-Max range report

[BoilerUP]

Rifle:
Savage 110 Long Action
Criterion 26" .260 Rem 8 twist SS varmint contour barrel
Savage 112 BVSS centerfeed stock, converted to staggerfeed
Nikon Monarch 5-20x44

Environmentals:
Partly cloudy
Temp 85°F, Dewpoint 53°F, ~32% humidity
675' ASL elevation, density altitude ~2400'
Partially shaded (tree) shooting bench
Rifle shot off bags
100 yards

Load specifics:
2x Nosler brass, neck sized with Lee Collet Die
WLR primer
Hornady 6.5mm 123gr A-Max
COAL 2.84, 0.010" off lands

Notes: I really need to bed my action/stock and don't have any velocities for these loads...my ProChrono & Miles Gilbert Bedrock kit are supposed to arrive tomorrow but I'm out of town on business so today was my range day. The bench also wasn't the most conducive to great accuracy, especially given my marginal but improving form.

Varget
38.5: 3 shots, 0.5" group. Two shots touching, one pulled high/left
39.0: 3 shots, .425" group. Two shots in one hole, one pulled high/right
39.5: 3 shots. 2 shots touching, one called flyer 1.5" high
40.0: 3 shots, 0.64" group, horizontal stringing. Showed pressure with Sticky bolt & brass flow

H380
42.0
42.5
43.0
43.5

All groups were garbage with sticky bolts, which was disappointing considering 41.5gr H380 with a 120 Nosler BT is my whitetail load and shoots very well out of this barrel, as well as my 22" 9 twist Remmy 700 Mountain LSS. Did not try the 43.5gr load due to sticking bolt @ 43.0gr.

RL17
44.0: 3 shots, 0.7" group. First two shots touching, third pulled .6 right
44.5: 3 shots, 0.61" group. First two shots touching, third called flyer .6 low/right
45.0: 3 shots, 0.46" group.

H4831SC
47.0: 3 shots, 1"+ group
47.5: 3 shots, 0.63" group. First two touching, third called flyer left
48.0: 3 shots. First two shots one ragged hole, got excited and pulled the third 1.25" up/right in a called flyer. This load looks to be VERY promising.
48.5: 3 shots, 2" group with vertical stringing
49.0: 3 shots, 0.5" group, ejector marks.
49.5: did not test due to pressure @ 49.0

My next test will further explore 48.0gr H4831SC +/- 0.5gr, RL-17 44.5 +/- 0.5gr, and Varget 39.0 +/- 0.5gr, with velocity data from the new chronograph!

 

[alf]

Nice job.

Give some H-4350 a whirl.

 

[Chuckw]

try some re15 as well.

chuck

 

[BoilerUP]

Had very limited time to load over the last couple weeks, but wanted to test out the new ProChrono today.

Looks like 48.0gr H4831SC pushes the 123gr A-Max to 3000fps from my 26" Criterion barrel using RP .260 brass. This load had an ES of 20 and a SD of 8. This load also exhibited the best accuracy of the 5 loads I tested today with no pressure signs despite being a little compressed; think I'll probably work +/- 0.2gr either side to try and find a sweet spot.

38.5gr Varget provided average velocities of 2867fps with ES of 37 and SD of 18; 39.0gr Varget averaged 2893fps with an ES of 18 and SD of 9.

My next range trip I'll likely explore W760 and RL17 along with fine-tuning the 4831SC load.

 

[tido250]

I'd like to hear more about the rl-17 loads.

 

[Raptor]

My 260s have loved H4350 with the 123 Lapuas. I also had one that shot very well with 40.5grs of varget and the 123s. All these loads cronographed at 3000fps or just shy of it in the 2990fps range.

With RL17 one of my guns shot in the .3s and .4s for 5shots at close to 3100fps. I only tested this load at 100yds though since I really wasn't intrested in using an powder that is not an "Extreme" powder.

I tried a box of the 123AMAXs and I could not get the accuracy out of them that I could the 123 Lapuas. I was disappointed with this because the 140AMAXs had all shot well in my 260s and 6.5x284s. When I rebarrel my one 260 I will try them again though. I am shooting a new 284 now with the 162AMAX and its a "HAMMER"!!!!!!

 

[AckleymanII]

Boiler, start at the start, get some Lapua brass, Nosler is soft in the case head.

AA4350 with 129g Long range accubond has shown some unbelievable accuracy with Great velocity.

No flies on 123 Lapua Scenar, accuracy and killing.

 

[0.1 Aggregate]

Ackleyman, start at the beginning yourself. This thread is over ten years old, I suspect that the OP has it figured out by now!

 

[AckleymanII]

So, how does your post help new guys/hunters reading the post for the first time?

260 Rem likes to run some pressures at the top end accuracy node. Run tough brass to begin with, you have a more harmonious outcome. Lapua brass eliminates a lot of "Sticky Bolt" issues on warm loads where the barrel is the most accurate. Lapua will have tighter primer pockets over a longer Period of time, also.