Can the 280AI Really Be this good! What is your experience with it?

[std7mag]

I'll agree with @Wind Gypsy.
Nothing magical about it.
Sits squarely between the 280 Rem & 7mm Rem Mag.
With all the numbers thrown about, it's the 6.5 Creedmoor of the 7mm world.
Some of the velocity numbers have me either 1) concerned over a very hot load or 2) total BS.
But i've seen the same from 7mm-08 loads too.

Surprisingly, i never see posts where 308 Win is as fast (or faster) than 30-06 loads.

 

[klampson]

I have rifles chambered in 280 Rem, 280AI, and two in 7mm Rem Mag. I have hunted extensively with all three cartridges, and I’m a huge fan of 7mm pills. The 280AI is a fantastic cartridge, and a great choice if you hand load. However, I’m still partial to the 7mm Rem Mag, especially when loaded to it‘s full potential.

 

[6mm Remington]

280AI 140gr. Nosler Accubond IMR7828SSC 64.5 grs. 3180 fps

158 yards broadside - shot tight behind the shoulder in the lungs
spun 180 degrees into the shot - did two somersaults and was dead - never moved.

I got the okay from my outfitter Matt Thoft owner of Ovis Outfitter's to use my 280AI on my grizzly bear hunt the fall of 2019. I was so fortunate to this opportunity to hunt with my wonderful guide Mike Lettis, and even more so when I got this beautiful bear. This was my once in a lifetime dream hunt. As you can see the 280AI I had built on a Winchester Model 70 Classic Sporter performed superbly. The first year I had this rifle I was using 140 gr. Partitions and the first animal I shot with it was a large cow elk at 450 yards. One shot and she went about 15 yards and tipped over. Next year I shot a nice doe antelope at 300 yards. One shot and I had my antelope again using 140 gr. Partitions. Later that year I shot a nice whitetail buck one shot at about 200 yards again using the Nosler Partition. This rifle shoots great and was mentioned it doesn't kick that badly. I did use the 140 gr. Accubond on my grizzly bear.

 

[Mustangs Rule]

I'll agree with @Wind Gypsy.
Nothing magical about it.
Sits squarely between the 280 Rem & 7mm Rem Mag.
With all the numbers thrown about, it's the 6.5 Creedmoor of the 7mm world.
Some of the velocity numbers have me either 1) concerned over a very hot load or 2) total BS.
But i've seen the same from 7mm-08 loads too.

Surprisingly, i never see posts where 308 Win is as fast (or faster) than 30-06 loads.

I can only relate my own experience all of which has been with Barnes bullets following the Barnes reloading manual.

Looking at the 120 grain, 140 grain, and 160 grain Barnes bullets and them comparing 7 Rem mag to the 280AI in the manual, there is no real difference except the 7 Ren mag uses much more powder for each bullet to reach max velocity.

That is the book now here is my own experience. I have reloaded only two bullets the 150 TTSX and the 140 TSSX. I did not have the ideal powders for either and my velocities were between the 280 and the 7mm Rem mag.

Digging around I found about a cup of a powder, R-19, which was one of the highly rated powders for the 280I with the 140 grain TTSX.

With way way less R-19 powder, as much as 15 grains and no less than 8 grains, comparing it to other powders for the 7mm Rem mag with this bullet, I reached the safe listed max for the 280AI and got 3172'/sec, and the absolute max listed velocity for the 140 grain in the 7mm Rem mag was 3199'/sec.

On top of that this load is a tack driver at 100 yards, 5/8" and is mild of recoil.

There were no signs of excess pressure and this was a by the book load that was only 29'/second under the 7 mm Rem mag

 

[ImBillT]

It’s practically a 7mag, but with less powder and longer barrel life. What’s not to like?

For everyone shooting light bullets. It’s a 7mm for crying out loud. 168gr should be the floor. 140s are are for 6.5s!

 

[VikingsGuy]

coz it's 4 bigger?

 

[VikingsGuy]

I'll agree with @Wind Gypsy.
Nothing magical about it.
Sits squarely between the 280 Rem & 7mm Rem Mag.
With all the numbers thrown about, it's the 6.5 Creedmoor of the 7mm world.
Some of the velocity numbers have me either 1) concerned over a very hot load or 2) total BS.
But i've seen the same from 7mm-08 loads too.

Surprisingly, i never see posts where 308 Win is as fast (or faster) than 30-06 loads.

#hammers_allthespeed_noneoftheBS

 

[ImBillT]

I'll agree with @Wind Gypsy.
Nothing magical about it.
Sits squarely between the 280 Rem & 7mm Rem Mag.
With all the numbers thrown about, it's the 6.5 Creedmoor of the 7mm world.
Some of the velocity numbers have me either 1) concerned over a very hot load or 2) total BS.
But i've seen the same from 7mm-08 loads too.

Surprisingly, i never see posts where 308 Win is as fast (or faster) than 30-06 loads.

Actually the 280AI does in fact get very close to the 7mag, and there’s no magic required. The higher the case volume/bore area ratio, the less gain you get by increasing case capacity within normal barrel lengths. The work done by a gas is the average pressure multiplied by the area of the surface it’s working against, multiplied by the distance it can work over. Larger cartridges can only increase muzzle velocity by having a higher pressure AT THE MUZZLE than smaller cartridges(assuming peak pressure is the same, and for modern cartridges in bolt actions specified pressures are generally fairly close). There’s a point at which adding more powder without increasing peak pressure isn’t really increasing muzzle pressure very much. Longer barrels push that point upward. Shorter barrels push that point downward. Developments in newer slow burning powders have also pushed that point up slightly, but you’re talking about a handful of powders, not the whole sweet of powders that are available. Looking at various cartridges and 24”-26” barrels, you’ll find that the point at which larger cases begin to yield little to no increase in velocity is around 1075-1150gr H20/in^2 of bore area.

Below are some cartridges known for great performance, but not known for melting barrels, or being nearly matched by a lot of smaller cartridges.
22-250= 1091
270Win= 1095
257ai= 1157
280ai=. 1152

Below are some questionably over-bore cartridges that only stand out above a number of smaller cases when specific powders are used. The 6.5-284 and 220Swift are known for melting barrels, and according to the the guys who tried shooting HBR and F-Class with a .243Win, it doesn’t have much barrel life either, but it could potentially stand closer to the 257ai and 280ai, but the 6x47L, 6CM, and 6XC all but match its performance and boast longer barrel, which certainly suggests that it has crossed the tipping point.(6XC is 1041)
243Win= 1164
6.5-284= 1206
220Swift=1218



7mag=1326

This explains the near magnum performance of the 280AI, despite the fact that it produces less recoil and has longer barrel life(both of which are a consequence of using less powder).

 

[Esb]

Here is an interesting comparison of the 280AI and 7mm:

And the 280AI vs some of the newer short action 7mm:

 

[squirrel_hunter]

Hi i am new here. I just ordered a Browning xbolt 280AI. It has a 26 inch 1@8 twist barrel with a muzzle brake. Several guys told me H4831sc was one too use. RL 22 and RL23 are good powder for it also. I have a 280 rem and 7mm mag. I have always wanted a 280AI. I am planning on trying hornady 162gr eld m. And 166gr A Tip. If i can ever get my hands on berger 175gr elite hunter too try to. I have 140gr and 168gr vld hunting bullets on hand.

 

[Brian in Montana]

I've never owned a 7mag so I really can't make the comparison by experience, but I am say I've been impressed with what my 280 AI will do. Mine sure seems to like RL23. I recently worked up a load using RL23 pushing 160gn Accubonds. Averaging 2920fps its about .5 MOA. There is just not much to improve on with that and nothing on this side of the pond I wouldn't shoot with it. So nothing is magical, but the 280 AI is certainly impressive.

 

[old roper 42]

I've own few Ackley's and in Ackely book Vol 1, this is comment about 280 Improved.

An interesting comparison can be made by studying these figure (load data) with those from for various 7mm Magnums, like Weatherby or Ackley. It will be quickly noticed between the top velocities for the 280 Improved, and the Magnums, plainly demonstrating that there is little advantage in using a belted Magnum case, for anything under 30 cal.

That reason I build 280AI wildcat.