.280 Ackley load road map

adk hunter

Well-Known Member
Joined
Apr 1, 2018
Messages
577
Location
Chestertown N.Y.
I am beyond excited to have my new .280 Ackley.
specs: M70 Pre-64 lilja #4 fluted 21.5" vx-6 2-12 firedot 1-10 twist

Best to start with seating depths, power charges or bullets??

I am not interested in filling the case with lead or copper so 140-160's will do. I have many to weed thru. Wondering if I should just go with a 3.330 standard length and medium load of 4831sc and explore what the rifle likes first?

Magazine length is 3.368 and when I ran a 140 e-tip to touching it was 3.372...
So can't for the life of me get my mind around the smiths recommendation to seat a thousandth off, then 7 then 14. That will be too long to fit the magazine. Standard length would put it at .054 off. I could get to .024ish and still have a little wiggle room in mag. Hmmmm....

I do have several test loads all set since we had barrel ordering difficulties (Proof) Lilja was GREAT!
I will probably just shoot them today and see where they go.

Rifles purpose is general hunting, caring in the woods and capable of elk when I go west again. I like the ttsx, e-tip and have some lrab 150's too...

Joe.
 

carlbobh

Member
LRH Team Member
Joined
Jul 10, 2013
Messages
21
I'm using the 150gr Nosler Ballistic Tip with 60.9gr of RL22. 3207fps with a 4 fps dev. Under <.25". Gun is a Remington Model 30, Shlen Select Match #5 1-9 twist. 26" length. I fire form off the shelf Rem 150gr PSP, get ~2900 fps on it and under .5" groups. OAL is 3.330 and .127 off the lands. I think you have to treat these AI's like magnums and give them a little more room to get moving, give you better velocity and less pressure sensitivity.
 

adk hunter

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Joined
Apr 1, 2018
Messages
577
Location
Chestertown N.Y.
Super Thanks! I shot some today all were 3.330. 120 ttsx, 150 ttsx, 140 e-tip and some factory stuff. ( nosler ackley 140 ab and .280 150 partitions). The 150 ttsx were surely the best with two different charges and the 120's were good too. Had a nice triangle that was very near .5 MOA. Just have reloaded some at 3.340 and 3.350...
 

slas

Well-Known Member
Joined
Dec 12, 2017
Messages
353
Location
Shawnee OK
Just started working up a load in my Cooper Model 52 280 AI. I want to shoot the 168 Bergers VLD's since I shoot the 140's in my 260 and have loads already developed for hunting. I just did some 10 shot load development with H4831sc and Fed 215 primers. Started at 58gr and worked up to 59.4, of course watching for any signs of pressure. My rounds leveled out between 58.6 and 59 so I'll do some more testing within those weights. Speeds were 2900 to 2935 at those weights. I have a few other powders but, like you, I just started. My magazine allows up to 3.4 so I have the 168's sitting out to 3.39. Planning on working the 150's next.
 

DropT1ne

New Member
Joined
May 13, 2018
Messages
2
Location
Tillamook
Hello,

first post.

I am awaiting my Cooper timberline M 52 in 280 ai to show up at my local ffl. super exited! am topping with a leupy VX6 HD 3x18x44 firedot CDS. will post a couple pics when I get it set up.

I am interested in hearing your results on your loads. I am leaning towards 160 gr partitions or 140 gr accubonds.

Question - what is the best die set to get for this gun? I have gotten myself confused by reading all the saami vs not saami issues Nosler created.

Do I just get the redding 3 die set 40 degree? what are you all using?
 

adk hunter

Well-Known Member
Joined
Apr 1, 2018
Messages
577
Location
Chestertown N.Y.
I did get the reding set. What I could lay hands on more than expert intel. I love it for the finite adjustment seating bullets. Time will tell for the resizing die but have used that to run some new hornady brass thru. The nosler stuff seems perfect but wow you pay. Saw some hornady brass on sale cabelas for $20!!! got lots now woop. Also hope to try the gmx 139 gr as I found that bullet awesome in my .338 federal. I may sniff around the Bergers for fun groups but had a bad experience in the woods with them. I do want to find that one hole load but real life in the field performance will be what I base my hunting load on. I did get some matching groups from the 150ablr comparable to the ttsx so that may be good enough. (around .5moa)
 

L.Sherm

Well-Known Member
LRH Team Member
Joined
Jul 26, 2017
Messages
3,982
Call Cooper and find out what reamer they use, they probably could suggest what dies other customers have used. Get some RL23 works great with 140-162 class bullets
 

RockyMtnMT

Official LRH Sponsor
Joined
Mar 25, 2007
Messages
6,034
Location
Montana
With your 10" twist you should watch for marginal stability with your bullet choices. This may not show up at the range but can definitely give you sub par results on game.

How far are you intending to hunt with your rifle?

Steve
 

Blacktail

Well-Known Member
Joined
May 12, 2006
Messages
547
I am beyond excited to have my new .280 Ackley.
specs: M70 Pre-64 lilja #4 fluted 21.5" vx-6 2-12 firedot 1-10 twist

Best to start with seating depths, power charges or bullets??

I am not interested in filling the case with lead or copper so 140-160's will do. I have many to weed thru. Wondering if I should just go with a 3.330 standard length and medium load of 4831sc and explore what the rifle likes first?

Magazine length is 3.368 and when I ran a 140 e-tip to touching it was 3.372...
So can't for the life of me get my mind around the smiths recommendation to seat a thousandth off, then 7 then 14. That will be too long to fit the magazine. Standard length would put it at .054 off. I could get to .024ish and still have a little wiggle room in mag. Hmmmm....

I do have several test loads all set since we had barrel ordering difficulties (Proof) Lilja was GREAT!
I will probably just shoot them today and see where they go.

Rifles purpose is general hunting, caring in the woods and capable of elk when I go west again. I like the ttsx, e-tip and have some lrab 150's too...

Joe.

In my 280ai 26" benchmark carbon barrel 1:8.5 twist on a 700 action. i am running the hammer 143's right at the lands with 62 grains of H4831sc and BR2 primers to 2165 fps to .4" I cant wait to try the hammers on game they were accurate with just about any seating depth was getting 1" or less but settled on the load above at an OAL of 3.380 and I had plenty of room in the magazine. going to work up a load of 131 hammers for my daughters 7/08ai. If these peform as well as they shoot on game will be set and Steve is a great resource and great guy to work with!!
 

slas

Well-Known Member
Joined
Dec 12, 2017
Messages
353
Location
Shawnee OK
In my 280ai 26" benchmark carbon barrel 1:8.5 twist on a 700 action. i am running the hammer 143's right at the lands with 62 grains of H4831sc and BR2 primers to 2165 fps to .4" I cant wait to try the hammers on game they were accurate with just about any seating depth was getting 1" or less but settled on the load above at an OAL of 3.380 and I had plenty of room in the magazine. going to work up a load of 131 hammers for my daughters 7/08ai. If these peform as well as they shoot on game will be set and Steve is a great resource and great guy to work with!!
2165 fps or 3165 fps?
 

RockyMtnMT

Official LRH Sponsor
Joined
Mar 25, 2007
Messages
6,034
Location
Montana
In my 280ai 26" benchmark carbon barrel 1:8.5 twist on a 700 action. i am running the hammer 143's right at the lands with 62 grains of H4831sc and BR2 primers to 2165 fps to .4" I cant wait to try the hammers on game they were accurate with just about any seating depth was getting 1" or less but settled on the load above at an OAL of 3.380 and I had plenty of room in the magazine. going to work up a load of 131 hammers for my daughters 7/08ai. If these peform as well as they shoot on game will be set and Steve is a great resource and great guy to work with!!
I am guessing that your are running 3165fps not 2165fps. :D

We are running rl-16 in our 27" barrel with 143g Hammer Hunters at 3213 fps. This is also an 8" twist. We also took this rifle to Africa a couple of weeks ago, running our 150g Sledge Hammer with H4831ssc at a mild vel just over 3000fps. This combo took wildebeest, blesbuck, 2 impala, waterbuck, warthog, and a jackal. All one shot except the warthog. 1st shot too far back, 2nd shot drt. 28 cal is considered marginal for African plains game. All of these animals were drt other than the wildebeest that went under 50y after a pure lung shot, the blesbuck went 10' (pretty much drt) and of coarse the pig. One impala was a drt liver shot. I was most impressed by this as it would normally result in a long track.

The 10" twist will fully stabilize the 131g Hammer Hunter or any of the Sledge Hammers up to the 150g.

Congrats on the new rifle! Have fun with it, the 280ai is a great cartridge.

Steve
 

wsq

Well-Known Member
Joined
Mar 1, 2016
Messages
266
Take a look at bullets.com Redding dies close out great prices you may want to try reloader 23 the cooper mag want let you load long enough for the vld's but the one I had shot the classic hunter Berger 168's into one hole with 58 grain of reloader 23
 

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