Anybody run a long throated .260 Ackley?

[codyadams]

So I'm wondering if there is anyone that runs a long throated .260 AI, and what kind of performance they are seeing. I get pretty good performance as is with my SAAMI .260 throat length .260 AI, granted I have a 30" barrel, but wondering what I can expect or if anyone has a guess. I know I would gain quite a bit of capacity, the bullet is pretty far in the powder column. Will be switching to the 156, which would be even farther down in than the 140.

Anyway, thanks all.

Cody

 

[jimbires]

Cody , I just kind of started playing with a standard 260 with the throat lengthened . I'm not sure if I can tell you anything helpful . I thought I'd be using 120 - 130 gr bullets to keep the velocity up , I'm pleasantly surprised with the velocity I'm expecting from a 140 . I'll be really interested in what you come up with on the 156's .
25" bbl , lapua brass 54.33 gr water capacity .

125 gr partition , 46.3 gr RL17 , cci 200 primer , 3110, 3107, 3101 FPS 0.025 jump 2.880 coal off the tip .

140 nosler ballistic tip , RL 26 , cci 200 primer , looks like it likes .005 jump 2.928 coal off the tip , I'm expecting velocity to max out right at 3000 FPS , using 50.1 gr RL 26 .

 

[codyadams]

Cody , I just kind of started playing with a standard 260 with the throat lengthened . I'm not sure if I can tell you anything helpful . I thought I'd be using 120 - 130 gr bullets to keep the velocity up , I'm pleasantly surprised with the velocity I'm expecting from a 140 . I'll be really interested in what you come up with on the 156's .
25" bbl , lapua brass 54.33 gr water capacity .

125 gr partition , 46.3 gr RL17 , cci 200 primer , 3110, 3107, 3101 FPS 0.025 jump 2.880 coal off the tip .

140 nosler ballistic tip , RL 26 , cci 200 primer , looks like it likes .005 jump 2.928 coal off the tip , I'm expecting velocity to max out right at 3000 FPS , using 50.1 gr RL 26 .

My load with the 147 and a standard saami throated .260 AI is 51 grains, going 3040 fps. Looking at your data, there seems to be some significant gains to be had

 

[LongBomber]

Mine not super long, but its longer than sammi standard. I got a wyatt ext mag box, which gives me just under 3" oal. I mainly run h4831 in mine so my speeds are a bit lower than they would be with rl17 or 26. From a 25" barrel
140 vld- seated with only the boat tail seated below the neck, I run 47.5gr to get 2845fps, but I can run up to 48.5gr/ 2950 before I get pressure signs.
I tried rl 17 and the 129 lrab I could run up to 3170, but accuracy was best at 3035fps.
The 147eld can run 2920 before I hit pressure. With a longer barrel and if I set it up for single shot I think those could be pushed over 3k fairly easy.

 

[jimbires]

I got out after work tonight . 140 gr Ballistic tip , .005 jump COAL 2.928 off the tip , 50.0 gr 2998 fps , 50.5 gr ( quickload shows this as 0.4 gr over max ) 3009 fps . no pressure signs .

I started to test seating with the 129 gr accubond long range bullets .COAL to touch is 3.012 off the tip . starting load of 48.0 gr RL26 gave right at 2900 FPS . should max out at 52.3 gr and about 3100 - 3125 FPS