Help with a 260 REM Load

[rhouser]

I set up a ladder with the Hornady 129 SST and H4831SC for my 260 Remington 700 Mountain rifle (22" skinny barrel with a pressure point).
I found a really nice node at 45.0 grains (.48" 5 shot group).

Problem: My Hornady Manual is so old it doesn't even show the 260 Rem. My Lyman 49 doesn't show the Hornady SST 129. Hodgden Powder site doesn't show the SST 129. I am looking for a published MAX load for the SST H4831SC combination.

I have absolutely NO pressure signs at the 45 gr Node. I am guessing that there may be another node "up the ladder" with the same accuracy, but, with a little more "kick a**" to it. Velocity is not my goal, terminal ballistics on target are, so I am really happy with finding the 45.0 node. I didn't bring my chronograph yesterday, but, am guessing the 45.0 is on the lower end of the velocity for this cartridge.

Thanks for any help and/or advice in advance.

rc

 

[johnnyk]

rhouser,
Hodgdon's website list 48.0 as max and compressed for the 125gn Partition. Didn't find any info at reloadersnet.com on the 129gn with H4831SC. I would take my time about getting to 48.0 with that 129gn bullet. Things may get sticky on ya. JohnnyK.

125 GR. NOS PART H4831 2.780" 45.0 2725 51,600 PSI 48.0C 2862 58,000 PSI

 

[trebark]

Here's a site that I have used when looking for max load data. I've used this site for many loads (280rem and 308). Always approach maximums carefully...

This site shows 49.9 as the max load of H4831 with a 129grain bullet....

264_12_129

 

[eshell]

I don't have my data in front of me, but I tried H4831SC in my .260 with 139 Scenars, hoping that I could use this powder in both the .260 and the 6.5-284.

I found a great accuracy node, just before seeing high pressure indications, but when I went afield with it, long range drop was more than my .308/175 SMK load. I chronographed it and velocity was just above 2,550. For a .260, this is dismal.

If one is looking for terminal performance, a heavy bullet at 2,600 (the .308/175 factory load) exceeds the 6.5/139 at 2,550 by a very good margin.

I currently use H4350 in my .260 with 130 Normas and get 2,950, and other than the slight energy edge provided by my 6.5-284 running 142 SMKs at the same speed, it is nearly as effective for long range.

 

[rhouser]

eshell, I will run a 4350 ladder. I may do both IMR and H since I have them both. Down side is ALL that EXTRA Shooting.... I love it. Next time I will bring my chronograph, but, that 45.0 load of 4831sc sure did shoot... rc

 

[eshell]

eshell, I will run a 4350 ladder. I may do both IMR and H since I have them both. Down side is ALL that EXTRA Shooting.... I love it. Next time I will bring my chronograph, but, that 45.0 load of 4831sc sure did shoot... rc

I think you'll be pleased with the H-4350 results, both accuracy & velocities possible.

I have a GAP .260 built on a Remington action and it shot the H-4831SC load into one hole, but they dropped like rocks due to the low velocity.

 

[Locknload]

Ok, you are looking for terminal performance at distance. Change the thought process. You will need to switch bullets and powder so you can use the case capacity to its maximum effect and use the heaviest bullet (best BC and SD) that will stay super sonic past 1,000 yards if you truly want long distance performance. The idea of the 260 is not to push heavy bullets to achieve the result you are looking for, because the limited case capacity simply will not give you what you want with a heavy bullet.

What you are looking for in combination is H-414 which was developed specificly for the 22-250 (similar case capacity) and the 120 gr Sierra HPBT MK. The max load in three of my rifle guns is 48 gr which produces an average velocity of 3,206 fps with all three grouping at sub .20 inches. Start at 45-46 grains and work up in your gun. My 260 rifle guns are all 1-8 twist and all have 26 inch barrels. I seat the bullets to .003 off for the bolt guns including the XP-100s and .050 short of mag length for the AR which I have throated to be .003 off as well, at that mag setting, with the 120.

Just plug in what you have and what you want, in a ballistics program, and then compare the data to what I have posted.
Best,
Ed

 

[CapDog]

My .260AI has a 24" barrel. As such I could not get the velocity I wanted with H4831, just not enough barrel to take advantage of the slow burn. As soon as I switched to H4350 speed came right up. Same held true in a couple 6.5x55's with shorter barrels.

H4350 and .260's seem to go hand in hand.