260 Remington Long Range Load Development

[HTSmith]

I've acquired a used f class rifle that is being rechambered to 260 Rem with a long throat. I'd like to go about load development in the most efficient manner. Components are Lapua brass, H4350 Powder, Fed 210 Match primers, and 140 Berger VLD's. My plan is to find a powder charge and then tune with seating depth. Is that a reasonable approach? What range of charges should I try? Anyone have a ringer load with these components? Thanks

 

[double g]

43 grains has been a starting point in alot of barrels for me, some will shoot alittle stiffer load you might want to start alittle lower. DG

 

[drumcorpschamp]

Please do not START at 43 grs. of H4350. Maybe 40.5 or 41 grs. You can always go up and find where your gun starts seeing pressure signs.

Your choice of components is sound in my experience and I am sure you will have success. A chronograph is your friend and will help you establish where the nodes are.

For efficient load development, Eric Cortina shared his method of long range load development in a thread in this forum. http://forum.accurateshooter.com/index.php?topic=3814361.0 I went to school on that thread and am now finding good, solid performing 600 and 1000 yard loads much quicker than my previous methods.

Good luck and enjoy your .260.

Jerry

 

[Jet]

I agree with Drum. I have two 260s and both shoot exceptionally well with 40.7gr of H4350. One likes 139 Scenars the other likes 140 Berger Hybrids. These are a bit slow but at 600 they hold their own. I have been able to run up to 44 gr when the temps are cool but as soon as the temps warm up I get blown primers, expanded primer pockets, etc.

Your components should work just fine. Work up in .3gr increments until you find an accuracy node then adjust seating depth.

Good luck and good shooting.

Jet

 

[DocDoc]

Berger lists 41.1 gr of H4350 as max with their 140 grain bullets. Hodgen lists 42 for the 140 grain Nosler partition and 44.5 for the 142 gr Sierra HPBT. So check multiple sources and start 10% below max.

 

[brian427cobra]

I had better accuracy with CCi primers in my 260

 

[spclark]

Start at 40.0 grains, seating the VLD'S 0.020" off the lands. Work up to 42.0 by 0.4 grains at a time, 0.2 grains after that. If you can test at 300 yards your results will be clearer than at 100 yds.

 

[HTSmith]

SP, you answered my next question--what seating depth to start with. My only other experience with Berger VLDs is the 105 6mm. I must have gone through 50 rounds of various "jams" with no luck. Then I started backing off the lands. .030 off was magic.

 

[wrongside]

I live in Michigan, do I have to wait for warmer weather? I know how cold weather changes speed and everything. One guy I shoot with kicks up his powder charge 2 grains in the cold. Thanks!

 

[jonbearman]

Do any of you have any of the 120's or 123's that you have tested? I am curious if others play with the lighter bullets in the .260?

 

[spclark]

Then I started backing off the lands. .030 off was magic.

For years I heard - and believed - VLD-type bullets just had to be jammed to expect any decent accuracy. Then one day I was going out to begin load testing for a new rifle, grabbed a box of ammo loaded for another rifle thinking it'd afford a good 'base line' velocity against which I could compare the loads I'd made up.

The last-minute grab shot markedly more accurate at 600 yards than most of the loads I'd made specially for testing. These were Berger 105VLD'S seated nearly 0.060" off the lands of that new barrel.

Ever since that day I've started testing at 0.020" off & been pleased with the results. Recently I found seating 0.005" off was just as good with the same load, useful info when anticipating match conditions that may see elevated range temps. That extra 0.015" comes in handy when the deeper-seated load might have pressure problems otherwise.

 

[spclark]

I live in Michigan, do I have to wait for warmer weather? I know how cold weather changes speed and everything.

The air density may have more of an effect than just the lower temps on your choice of propellant.

Colder temps will affect the "tune" a given barrel + action sings also; cold metal rings to a different harmonic than when at more moderate temps.

I generally try to test when it's no colder than 50 F if for no other reason than it's no fun trying to be patient & consistent all the while my fingers are growing numb....

 

[vtmarmot]

I have used 123 AMax in a .260 with 30 inch Krieger barrel with a SAAMI chamber and 1/8 twist. This was over 45 grains of H4350 at 3000 fps and accuracy wasn't much better than 1/2 MOA. I didn't experiment much with seating depth but kept it about .020 off the lands. I have recently tried 140 Nosler Custom Comp jammed and I think 43.5 H4350 and got much better accuracy.

 

[Ring31]

ive had 3 260's, if you research h4350 accuracy loads, the ALL fall from 42 to 43.5 in 140/142 class bullets.

my shillen best load was 42.3, and started maxing out PSI at 42.5

my CBI was best at 42.5, but didnt max out till 43.5

my kriger is best at 43, and never hit max, tested up to 43.5

CCI 200 primers, rem and LC brass

my advice is start at 42, go up .3 at a time from there

 

[cfreeman]

I have a .260 Barrel for my T2K that I tried the 140 VLDs with. Shot very well with 42 grns of H4350, .010 off the rifling. I don't like jamming bullets so that's where I started. 200-12x on a 600 yard prone target. You could probably play with the load and get it better. I was using Remington brass though, so you may want to start around 41, 41.5. I don't know what the capacity difference is between Lapua and Remington, but I'd suspect it's slightly less than Remington. My go to load is with the 142 SMK .015 off, 42 grns H4350, Federal 210. I think that's probably right in there with other good .260 loads, so if you start around 41 and work your way up, you should be good. I've seen some crazy (to me) stout loads out there for the .260 on forums, so be careful. I think you're gonna enjoy it. I bought mine used and it just hammers. You might need to pay attention to the wind a little more than with something like a 6.5x284, but the recoil is pleasant and it's just a very accurate caliber. I've had good luck with just about all the bullets in the 140 class, again, on a prone target, but you could probably tune them to be very competitive on an F target.

 

[KenO]

I used to shoot a .260, I couldn't get the 140 VLDs to shoot tight with my barrel. The 142 SMKs worked much better. Just saying to try different components. The SMKs were jammed at 20 thou.

My 223 bolt gun didn't like SMKs, and a few Berger varieties, but like magic tightened up with the Berger 82s. The 82s didn't seem to care if they were jammed or not, I run them with a 15 thou jump.

Back to the .260.. for 600 yards I used VV150 with the 142 SMK, and for 1000 yards 4831sc ended up being my load. The latter was close to 6.5X284 velocities, seems around 2900. Don't have my data handy.

I live in northern lower Michigan and did workups in the winter. Use a magic marker to label the brass, and put them in your pockets so your body heat keeps them at a consistent temperature, pull one at a time out to shoot.

I snowbird in Florida now, I don't have the 260 data with me, but it wouldn't help a whole lot anyways, other than get you close, every barrel is different.

 

[HTSmith]

Good stuff. I got 300 of the 140VLD's with the deal so that is the bullet I'm focused on. I do have some Sierra 142's to try also. All advice much appreciated.

 

[HTSmith]

I ended up with a load of 42.0 of H4350, Fed 210Match, Lapua brass, and Berger 140 VLD Jammed .010". Could have gone hotter but need this expensive brass to last. Same load .010" off the lands was almost as good. Thanks for all the input and advice.

 

[spudgun]

The topic of this thread is exactly what I'm looking for. I am working up my Rem 700, 7mm mag for long range shooting. Different caliber but same principles apply I think.

I was also playing with the bullet jump to the rifling. Today I placed a bullet much longer than the OAL specs. After closing the bolt I removed and measured the OAL of the cartridge. Found that the seated bullet measured .166 longer. I decided to divided it by 2 and add to the factory OAL.

In my mind this would indicate a .083 jump to the rifling.

I have read and read about the jump but it seems that every gun and caliber is different.

Is there a sweet spot or do I need to experiment?

 

[#40Fan]

Experiment, but make sure you have enough bullet in the neck to keep it there.