Load Dev for custom LR 280 AI

Dwh7271 · Mar 17, 2017

Did you use the 3.55 - 3.60 Ba? Mine was a standard Ba without the case capacity. Glad you could help out. It was hard for me to tell without owning a 280 AI. It was the best I could do.

Yesir. 360. And no big deal. I've just done a bunch of monkeying with 26.

So are we at a consensus that 58gn start 61gn max should be a good safe change?

Yes but..... :grin: It's going to depend on your rifle, case capacity, conditions, etc. etc. Just do the standard start low and work up. You should be ok.

brikwhitt · Mar 17, 2017

Will do..Velocities should be telling of where I'm at.

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jmad_81 · Mar 18, 2017

NWBlacktail":8exma2jk said:
brikwhitt":8exma2jk said:

So are we at a consensus that 58gn start 61gn max should be a good safe change?

Click to expand...

Easily. that's about my min/max with the 168 grain bullets and RL26. I just barely hit pressure at 60.5 grains RL26 and 168 grain Berger VLD.

For me, 24" barrel, 168 grain Berger VLD, Nosler brass, Fed 215 primers. Pressure is at 2950 fps using 60.5 grains RL26.

hope this helps, good luck!

I use this exact same load with the 168 ABLR but with WLRM primers. Same speed as above and shoots lights out!

longrangehunter · Mar 18, 2017

SJB358":e87m9bah said:
I would likely skip the .3 increments to be totally honest. Use 1 full grain increments and see what the speeds show on your chrono.

Since it is an Ackley, you might be able to drive that cartridge very hard before you see traditional signs of pressures, AND RL26 is very tricky stuff since you can keep adding powder and speeds will keep rising without a clue until you hit PSI's which are usually off the charts.

If you are just looking for speeds, I would just chrono them and see where you wanna work at FPS wise, then if you have the need to tweak it, then break it down into smaller increments. Unless you are planning on doing a ladder test or similar I can't see breaking down the charges that small until you are working for an accuracy load. Most of the time the speeds will be hard to see on a chrono with a .3 grain charge in a case the size of the 280 Ackley.

Just me, but I haven't found the need for Magnum primers with standard cases and RL26 yet. Some say they help, but I tried them in the 243, 25-06, 6.5 Swede and 270/7mm WSM and didn't see where they did anything better for me in my rifles, but they certainly shouldn't hurt either.

Have fun and post up your results. Can't wait to see what it does. It's a sweet looking rifle.

Very Sound advice given you are just getting going into this. The Nolser Data can get you started safely, plus the 280 AI has been around forever that certain powders just work well with a given bullet weight that I'd look there? I use IMR-4831 with the 150 NBT, and IMR-7828 w/the 175 Partition, and yes, H-4831SC works well to, but so does RL-22, and RL-25 FWTW.

With a AI it's best to stay within the expected velocity for a given bullet weight and not go looking for pressure signs unless they arise working up to those speeds.

Good luck, and just use some common sense. A accurate round trumps speed any ways.

brikwhitt · Mar 19, 2017

Longrangehunter thanks for the advice.
I do appreciate it, but dont worry. When it comes to setting off a small detonation at the tip of my nose, I tend to excercise caution. This isn't something I'm unaccustomed to, I like to ask advice when it comes to a caliber which I have little experience loading for, and with a powder with little available data.

So far brass is sorted by case neck thickness, and checked for runout. Nosler brass is looking good so far. The 24 I plan to load today have a thickness variation of .0007. Not to shabby. I jad more with .001- .0015. I Wanted to start with good brass up front. The total indicated runout varies from .000- .001 with one being .0015. I know they will be more concintric once fired in my chamber. So I'll evaluate my dies once they have been through first firing.

I will be using fed 210 primers. I decided to forgo the mag primers untill I evaluate ES across a wide string once I settle on a load.

I dont want to get to far ahead of myself right now so finding a safe max load will be the order of the day first time out.

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brikwhitt · Mar 19, 2017

Oh yes, and fresh batch of battries bought for the crony

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brikwhitt · Mar 19, 2017

Ok I finally got all my chores done. Scope is mounted, and ammo is loaded. Maybe next weekend I'll take her out for a dance.

The Nosler brass loaded great. I started with 58gns and loaded 3 rounds, loaded the next three 58.5 so forth and so on untill I reached 61.0gns

As good as the nosler brass was, the primer pockets were shallow. I used my uniforming tool to deepen the pockets and wr were off to the races. Bullet runout ran anywhere from .001 - .002 of total indicated runout. I had two that went .003 but I figure after fire forming them to my chamber, I'll be more apt to evaluate my dies, but for now the redding comp seater die appears to be solid.

Checking neck diameter before and after it seems nosler is going with .002 neck tension. I will most likely go with .0015 . I did swab the neck I.D. with a graphite and a q-tip before bullet seating.

Hope all goes well when I get her to the range.

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