280ai powder suggestion

[Hammer101st]

7828 doesnt get enough credit i had a killer load worked up in a 243 with 7828. Now i use it in a 6.5x55 swede AI with 150grn match kings at a little over 2800

 

[ImBIllT]

Had trouble fitting enough RL-23 in a case behind a 180VLD, N560 was probably just about perfect for max velocity. With a 168, I would assume you would be slightly better off with a slightly faster powder like N555 or H4350. Might not get any extra velocity from 4350 being a single-base powder, but it might match N560 for velocity and come with all the advantages of H4350.

 

[L.Sherm]

Had trouble fitting enough RL-23 in a case

How much of the bullet was stuffed down in the case, I had no problem getting 64.00 in a 280AI case of RL23 with a 140

 

[ImBIllT]

How much of the bullet was stuffed down in the case, I had no problem getting 64.00 in a 280AI case of RL23 with a 140

I’d have to measure, but not a ton. Frankly the powder was near the case mouth though, and that’s after lots of tapping with the funnel over it to get it to settle.

I was using RWS 7x64 brass.

 

[L.Sherm]

I would imagine you were only up around 58.0 - 59.0 at the most.

 

[ImBIllT]

I would imagine you were only up around 58.0 - 59.0 at the most.

From notes it looks like 60gr was the most I crammed in there.

Looked like I got 61.5gr of N560 and got more pressure signs than I wanted, and eventually settled on 60.5gr N560 pushing a 180VLD at 2950fps from a 27” Lilja. From that I’d say that perhaps N560 could still be good behind a 168gr bullet, as there should still be room in the case even behind the 180.

COAL was not recorded, as I seat out until I get a square mark on the bullet, then zero the die, and only write down numbers from the die mic. If I chance bullets, I’ll write down the length of the seater die. Whatever the COAL, it would not fit in an Accurate 30-06 mag, so I ended up knocking out of the plastic spacers.

 

[L.Sherm]

Maybe its the brass your using, I was using older RP 280 that I fireformed and if my memory is correct I believe 64.0 was just right at the neck shoulder junction.

 

[ImBIllT]

Maybe its the brass your using, I was using older RP 280 that I fireformed and if my memory is correct I believe 64.0 was just right at the neck shoulder junction.

While the brass could certainly contribute, I doubt it would account for a full 4gr. Maybe the brass, combined with the possibility of a tighter chamber. More realistically, I likely had only one firing on the brass, and I suppose it’s possible that it wasn’t quite fully formed.

Honestly I wanted to use RL-23, and the possibility of getting 63+ grains in the case is worth investigating. I may need to see how much I can fit in a case today, and if it’s not close to 63gr, I might try firing the same case a few times and checking again. If it’s still not close, it might be worth snagging one piece of Lapua brass to test.

 

[ImBIllT]

Maybe its the brass you’re using, I was using older RP 280 that I fireformed and if my memory is correct I believe 64.0 was just right at the neck shoulder junction.

Well, I just tested it in fired cases. I got 67.1gr to the case mouth with RL-23 and 63.5gr to the neck/shoulder junction. With N560 I got 70.8gr to the case mouth, and 67.0 to the neck/shoulder junction.

My experience with hot loads and neck sizing is that hard bolt closes are looming nigh. I don’t have any sized cases, and my press is out of reach at the moment. I’m in the process of moving all my reloading equipment to the garage.

If I could get 63gr in a sized case, I’d probably want to switch to RL-23.

 

[L.Sherm]

My guess is you won't be over 59.0 with RL23 and will if not hit pressure be close with a 180.
I hit pressure at 64.0 with 140's and this was with 3 -24" barrels

 

[ImBIllT]

My guess is you won't be over 59.0 with RL23 and will if not hit pressure be close with a 180.
I hit pressure at 64.0 with 140's and this was with 3 -24" barrels

Well, maybe I hit pressure with less than preferable performance, but to my memory I abandoned RL-23 in favor of N560 because it was too bulky.

 

[Fire Dog]

You'll get the best speed with the N560 as it's the slowest on your list that Nosler lists for that bullet, and H4350 is the fastest you'd probably want to use. Varget, Big Game are probably faster than you want, and 7828ssc is probably slower than you want.

When I had my 280 AI, I used H4831sc at around 55.5 grains for that bullet.

55.5gr of H4831SC* is what I am using with Berger 184"s, 30 thou jump... Peterson brass
Very accurate. Using in F Open, 29" 1:8.5 barrel.
*{AR2213SC here in OZ where the powder is made... H just puts their own label on it...}
{Same for AR2208 = Varget}