.260 AI and 147 ELD-M powder selection??

[codyadams]

So far I have used H-4831sc, which works AWESOME for my 140 Bergers, single digit ES and superb accuracy, always in the .2"-.3" @ 100.

I have some more playing to do, but with the 147 so far I'm getting decent accuracy, .4"-.6" @ 100, but I know what this gun is capable of and want better than that. I have found my best seating depth, and was working on powder charges. I ran into slight pressure at 49 grains, which is fine because 49 was so compressed it was causing about .008" seating depth variances, at 48.7 there was about half that, and once dropped to 48.4 grains there was no variance.

I was @2,980 fps with the 49 grain load, 48.7 was 2,955, and 48.4 was 2,930, with the best accuracy, 48.1 was 2,905, and 47.8 was 2,875. BUT...my ES was around 20-30 fps with all loads. I'm using BR-2 primers, Lapua brass trimmed with proper neck tension...again, same components with the Berger bullet is giving me single digit ES.

Any suggestions on powder? I want this bullet going over 2900, I know I can get that (my 30" barrel helps) and I also want to lower my ES and hopefully tighten my groups up to what the Bergers are doing, in the .2-.3 MOA range. Anyone have any experience with the .260 AI and the heavier pills? Thanks for any help guys.

 

[Idaho Trecker]

Give rl 26 a try. I'm using it in my 6.5 Creedmoor with 140 and 147 eld m and 143 eld x. Great speed and es. Your added capacity will help out. If I remember right I can push the 143 at 2850 with a 22" barrel. Your added barrel length should add quite a bit of speed and with the slower burn rate of rl 26 vs h4831 the long barrel will help.

 

[codyadams]

Give rl 26 a try. I'm using it in my 6.5 Creedmoor with 140 and 147 eld m and 143 eld x. Great speed and es. Your added capacity will help out. If I remember right I can push the 143 at 2850 with a 22" barrel. Your added barrel length should add quite a bit of speed and with the slower burn rate of rl 26 vs h4831 the long barrel will help.

Another guy on here stated I should start my load around my top load of H-4831sc, being as I have no experience with r26, would you suggest the same? around 48.5 grains to start? There is not really any data at all for 260 AI, especially with the slow burning reloader 26.

Thoughts on H-1000?

 

[Idaho Trecker]

I would agree with his suggestion on starting point for you. I ran up to 49 grains I believe under a 147 but that was to find my max and that definitely was it on capacity and pressure. Another one that has worked very well for me in alot if cartridges including the creedmoor is hybrid 100v. My go to load with the 143 at the moment is with tbis powder and gets me 2810 fps ( all speeds i mention are over a magnetospeed) It's also pretty good on temp sensitivity with about .65 fps/degree. It's not bad when alot of the old rl powders and imr are 1.25 fps/degree and more. H1000 will probably work with your capacity but you won't get the speed of rl 26. I did temp test with rl 26 and came up with about .35.

 

[codyadams]

I would agree with his suggestion on starting point for you. I ran up to 49 grains I believe under a 147 but that was to find my max and that definitely was it on capacity and pressure. Another one that has worked very well for me in alot if cartridges including the creedmoor is hybrid 100v. My go to load with the 143 at the moment is with tbis powder and gets me 2810 fps ( all speeds i mention are over a magnetospeed) It's also pretty good on temp sensitivity with about .65 fps/degree. It's not bad when alot of the old rl powders and imr are 1.25 fps/degree and more. H1000 will probably work with your capacity but you won't get the speed of rl 26. I did temp test with rl 26 and came up with about .35.

I'll have to get some reloader 26 to try...what would you guess I could get for velocity with this powder and the 147? do you think it would do better than H-4831sc as far as velocity?

 

[drmarsh]

I'm just starting to develop my loads. I fireformed with 4831sc but have been getting better accuracy with varget. Using 38.0 grains, will chrono this week and let you know where i am speed. This is with 142 smk's but have some 143 eld-x's loaded as well with very similiar performance

 

[codyadams]

I tried Varget with the 100 grain hornadys for fireforming and they shot awesome, haven't tried them with the heavier bullets yet.

I have some 147's loaded up with reloader 26, I loaded 48 // 48.5 // 49 // 49.5 // 50 // and 50.5 grains, and while it was compressed, my seating was still exactly the same through all rounds. I am going to chrono tomorrow, I'll report what I find. Hoping for over 3000 fps with safe pressure and good accuracy and E.S. !! We will see if this powder delivers.

 

[jakelly]

I don't own anything in this class, haven't played with anything either, but I'd try 7828SSC next. Several guys I share information with have praised this powder in similar situations.

 

[codyadams]

So I got to try out my loads with Reloder 26...and needless to say I am quite impressed. So here is my results....

Hornady 147 ELD-M, seated .050" off (C.O.L. of 2.865)
Lapua .260 brass formed
CCI BR-2 primer
Temperature while firing was 20 degrees F

48 gr:
1. 2843
2. 2877
3. 2865 // 2861 Avg., 34 fps E.S.

48.5 gr:
1. 2966
2. 2988
3. 2982 // 2978 Avg., 22 fps E.S.

49 gr:
1. 2977
2. 3006
3. 3022 // 3008 Avg., 25 fps E.S.

49.5 gr:
1. 3043
2. 3040
3. 3043 // 3042 Avg., 3 fps E.S.

50 gr:
1. 3043
2. 3073
3. 3059 // 3058 Avg., 30 fps E.S.

50.5 gr:
1. 3096
2. 3102
3. 3078 // 3092 Avg., 24 fps E.S.

As you can see in the pictures, there are no signs of being overpressure, no heavy bolt lift, no ejector mark. However, the primers are getting flat around the edges, so I know it is getting up there in pressure. I find it interesting that going from 48 to 48.5 increased velocity over 100 fps, while the rest of the .5 grain increases rendered right around 30 fps increase. Also, while this powder is supposed to be somewhat temp insensitive, this was shot at 20 degrees, so I'm interested to see what my velocity jumps to during the summer. And also, my most accurate load was 50.5 grains, averaging just under 3100 fps....which to me, is phenomenal considering the case capacity. At this point, with this performance, I'm switching to reloder 26 and the 147 ELD-M for good.

 

[Schnyd112]

Those are great numbers. RL 26 looks like the way to go. I know at least a couple guys that struggled to get 2900 with 140 class bullets and 4831, 4350, rl 17 & 19. When I get 2850 out of a straight .260 with a 28" tube, I didn't see the appeal. 3050 is a different story.

 

[Idaho Trecker]

I knew rl 26 would be the ticket for you. I did some temp testing and did a thread on it a while back and I came up with .35 fps per degree.

 

[KMG]

Impressive results! Reloader 26 is really turning out some, Magic Bullet like scenarios. It seems to be producing top velocities in many cases. I'm running it in my 6.5 SS, 280, 300 WM so far & am loading test loads for my 30-06. Looking forward to trying 26 in my 260 Rem soon. Been using RL17 with 140 class bullets with great results. Hoping 26 doesn't run out of capacity in a standard 260 with the 143 & 147's. Not a fan of compressed charges due to the propensity towards high ES numbers.

 

[jakelly]

Looks like you might be coming into another node. I'd like to see what 51-52gr loads produce.

 

[codyadams]

Looks like you might be coming into another node. I'd like to see what 51-52gr loads produce.

It may be too compressed to fit much more...The 50.5 grain load is coming to the base of the neck, so it is already pretty compressed with the 147's. I'm thinking though about loading 49.2, 49.5, 49.8, 50.1, 50.4, and 50.7 and seeing what happens. I'll sit down and do some thinking and see what I come up with