280 AI or .270

[Ridgerunner665]

No....it stops at the WSM.

Shouldn't be that hard to believe...the 7mm RSUAM has LESS case capacity than the Ackley...and it gets real dang close to the 7mm WSM...add a couple grains of powder, and PRESTO!...you have the Ackley running right along with it, until you get into really heavy bullets.

Its simple physics...if there is such a thing.


And going up in elevation makes them all shoot better...the air is thinner.

[reynolds357]

Simple physics dictates that all other factors being equal, a bigger case will give you a higher velocity. That is making the assumption that an ideal powder exists for for each volume. If a smaller case is beating a larger case, one of the other factors in the equation is not equal.
Roy Weatherby pretty much proved that point by necking the .378 WBY down to .22.

[Ridgerunner665]

That's exactly right...and explains why the Ackley does what it does...there are a few powders that fit it pretty good....MRP, 7828, Reloder 22...to name a few.

[Bart B.]

Ridgerunner, your altitude change point has been an issue for years. It's the reason sea level residents have problems with their BDC scopes at long range in high altitudes. People shooting their .308 Win's at the NRA Whittington Center's 1000 yard line at 6600 feet up never got on paper with their stuff on the 1000 yard line at Camp Perry's 1000 yard line at 580 feet altitude. Their bullets were hitting the dirt about 2 feet below and in front of the 6 foot square target paper. There's been a few who quit in disgust after shooting a dozen or so misses and their scorer didn't know how to watch the bullet's trace to get their sighters on paper.

[Unlicensed Dremel]

OK, but hold on a second:

The number one argument for the .280 AI is 7mm RM velocities with less powder and less recoil, all in a lighter handier rifle

taylorce, while you are correct that the truth value of that entire statement as a whole, is "false", due to 2 things: (1) there being so many "ands" in there (i.e. lighter rifle AND less recoil at the same time) for the reason you pointed out (magnum action=heavier receiver=equalizing felt recoil), and (2) It just doesn't *equal* 7mm remmag no matter how you slice it.

However, I wish to note that if you don't require the "ands" to all be true, by parsing the statement and then tweaking it some, there is a pretty good benefit

For example, these statements:

1. *Almost* 7mm RM velocities with less powder and less recoil, ceteris paribus (same rifle weight) - and no belt - and 1 more capacity (I think?).
2. *Almost* 7mm RM velocities with less powder and the same recoil, but in a lighter handier rifle - and no belt - and 1 more capacity.

both have "true" truth values, and that's saying something significant.

NOW, which one of you is going to start the ".270 WSM vs. .270 Win AI" thread?

[reynolds357]

I definitely wont start the .270 WSM vs .270 AI thread because I am not a fan of the .270 WSM. I am a fan of the .270 Weatherby. Having said that, I did just build a .270 WSM with a whole heaping bunch of freebore to try to get its less than stellar velocities up.

[old roper]

Ridgerunner665, No question we were not even since I had my velocity at 2850fps vs 3100fps you had and I had no idea were you lived.

If we were equal on the velocity I would used my 270Wby

[taylorce1]

Now don't go getting drunk on the .280 AI Kool-Aid as well. It's like the other day when you asked if heavy .224 bullets weren't better at 300 yards than light ones. In the grand scheme of things there is no real difference between any of the cartridges we've been talking about.

If we talk MPBR the .280 AI only adds 13 yards over the .270 Win on an 8" target. Again not a significant increase in range. So for a hunting rifle there is no real difference in range and performance between the .280 AI and .270 Win. Let's face it after MPBR all these rounds become pretty equal.

Run the numbers using the LRAB using .295 G7 BC for the 7mm at 3100 fps, then use .273 G7 for a 1:10 twist .270 or .291 G7 for a fast twist .270 both at 3000 fps. You'll be within 1-2 MOA in both windage and elevation out to 800 yards regardless of your elevation above sea level. You'll only see a gap of less than 150 fps and 190 ft-lbs of energy. None of this is a significant increase of performance on game even elk.

It doesn't change the fact that all are very adequate for the intended purposes of hunting everything including elk. There is nothing special to the shape of the AI case nor it's increased powder capacity. Plus if anyone has ever read PO Ackley's books, they'd know he didn't see a whole lot of benefit to improving any 06 based cartridge especially the .270 Win.

[Ridgerunner665]

For the most part, I agree taylorce1...but

There is a little something special about the shape of the AI case...it doesn't stretch as much, which makes it last longer.

And the difference you note between the AI and the 270 Win...is about the same as the difference between the 270 Win and 270 WSM...most folks think that is a significant difference.

And by the numbers...the 270 Ackley gains more than the 280 Ackley...going by memory, I believe the gains were reported to be 8.8% for the 270, and 7.7% for the 280, but that is with 2 different bullet weights...I read that somewhere online, forget where....performance gains aside...the case life improvement is ALWAYS there.


Found it...the heavier the bullet for a given round, the higher the gains
Ackley Improved comparisons to standard rounds... http://gunloads.com/castboolits/atta...9&d=1295041970

[Ridgerunner665]

old roper,
That Weatherby puts us about even...that little bit more speed makes up for the lack of BC....you're ahead by about 10 fps at 800 yards ( but losing ground after that )....calculated at 8,000 feet.

[Ridgerunner665]

I want to reiterate something here...I'm not trying to say any of these other rounds are inadequate.

I'm only trying to make it clear that the 280 Ackley deserves respect in these circles...like when somebody gets on here and asks "whats the difference between the 270 Win and 280 Ackley"...or "whats the difference between the 7mm WSM and the 280 Ackley"...give them honest, educated, and unbiased answers...I know that "unbiased" part is hard for some, but you can do it....I have faith in you.

Being honest and forthright about it isn't condemning your favored round...you have your reasons for what you chose, therefore it is right for you...but that doesn't make it "right" for everybody.

The 280 Ackley may be stealing some of the spotlight...but I reckon its earned that right...it hung around for 50 years as a popular wildcat, so I'd bet its here to stay...its standardized, components are easy to get, no belts, higher magazine capacity, better case life, better barrel life, and excellent ballistics....those benefits there, nobody can argue with.


If anyone has a right to be utterly disgusted with the success of the 280 Ackley....its Remington....they got so very close to perfection, not just once...but twice (280 Rem and 7mm RSUAM)...and missed it both times!!! They'd be wise to try to make up for that by being quick to offer factory ammo for it...

[Ridgerunner665]

Ridgerunner, your altitude change point has been an issue for years. It's the reason sea level residents have problems with their BDC scopes at long range in high altitudes. People shooting their .308 Win's at the NRA Whittington Center's 1000 yard line at 6600 feet up never got on paper with their stuff on the 1000 yard line at Camp Perry's 1000 yard line at 580 feet altitude. Their bullets were hitting the dirt about 2 feet below and in front of the 6 foot square target paper. There's been a few who quit in disgust after shooting a dozen or so misses and their scorer didn't know how to watch the bullet's trace to get their sighters on paper.

Bart,
Yeah...its amazing how many people don't realize what a huge difference altitude makes.

At 8,000 feet...with high BC bullets even the 7x57 (7mm Mauser) is a genuine 500 yard elk rifle....

150 grain Nosler Accubond LR bullets from the 7mm Mauser...and it can be loaded hotter than this, this is just a moderate load.



For comparison...here is the same load at sea level

[taylorce1]

No argument from me on the case stretch, the 40 degree shoulder pretty much stops all case stretch and thus eliminating trimming.

.270 vs. .270 WSM, don't care I don't own a WSM and never saw the point to jumping on that band wagon. I wouldn't turn down a WSM that was a good deal, but I don't know if I'd hang up my .270 Win for a WSM. Though I've got a couple of buddies that swear buy them.

Your chart is all fine and all that but it only compares the AI cartridge to factory ammunition speeds. Then there is the fact that it only focus on speed and there is no mention of accuracy. If you hand load to 3000 fps with a 150 grain bullet which is possible with several powders. This makes the difference of 100 fps vs. the AI and thus you have less than a 4% gain in velocity. Same goes for the 130 grain weight for the .270 Win. At best you'll only probably average a 100 fps gain over the standard 06 based case if you AI it when you're only loading for velocity.

As far as this discussion being unbiased by any of the parties involved, well that pretty much is a laugh. I've messed with a lot of wildcats over the last 20 years, so I'm biased to where I don't believe that most of them are not a worth while endeavor. You're biased in the fact that you bought the .280 AI and now you are trying to get everyone to agree with your reasoning for that purchase. None of us have presented an unbiased opinion on anything in this thread, so there is no need to pretend that it has been done.

[Ridgerunner665]

We'll revisit this in regards to accuracy in a few months

They're telling me October/November...

[Unlicensed Dremel]

OK, OK, I reject the koolaid. : But appreciate very much Jim Jones's - I mean Ridgerunner's careful analysis.

[Ridgerunner665]

I'm not trying to get anyone to agree with what I bought...I bought what I wanted and needed...with 30 years of rifles under my belt, I can decide for myself...I don't give a rats behind what anybody else thinks of what "l" got for myself...and don't appreciate you implying that that is my motivation.

You're wrong...

And Jim Jones? Really....that was a bit much too.

And here I thought we were having a good discussion.

[Unlicensed Dremel]

No, hey, I'm just kidding. I'm just messing with you, since taylorce said something about "koolaid". You know a lot more than I do, and you've backed up your assertions with careful proof. There's no right or wrong here. I had a .280 AI and still believe it's one of the best goldilocks rounds going, with a solid reason for being. Please don't let my jack-arse comments discourage the excellent discussion.

[old roper]

Ridgerunner665, I lower the 270Wby velocity to match yours on paper so don't feel too good about your 280AI.

Problem you got is again, you haven't even loaded or have rifle don't even know if 3100fps at 800yd would be accurate load much less 1000yds.

Nosler used 26" barrel for the 150gr max velocity was 3107fps and Hodgdon used 24" barrel for 150gr max @ 2932fps. Nosler has Trophy Grade LR ammo and 280AI with 150gr ABLR is only 2930fps.

My wife's 280AI with 25.5" Kreiger barrel she shoots 150gr TSX she was max mid 2900fps with H-4831sc using Nolser data then changed over to IMR-7828sc and just little more than max load velocity at the low end 3100fps.

[Ridgerunner665]

Last post I'm making here until I get the rifle...then I'll come back and show what happens.

[Unlicensed Dremel]

OK. Keep us updated please.

[Ridgerunner665]

One little update...just acquired a few boxes of 160 grain Nosler Accubond bullets.

If those work out, I may never try the Accubond LR bullets, lol...I'm thinking about canceling the backorder for those bullets

BC of the 160 is .531, which is pretty accurate based on what I can find...and lots of 280 AI's are really accurate with them at about 3,000 fps...not quite as flat shooting as the 150 ABLR but still pretty darn flat, and it gets to 800 with enough velocity to expand.

[Ridgerunner665]

I did cancel the backorder for the 150 grain ABLR's...I may still try them in the future.

I have a few rounds loaded...some with 140 Accubonds and some with 160 Accubonds...still no rifle yet.

[Ridgerunner665]

Spoke to Nosler today...looks like it will be at least the last week of November before I get the rifle, maybe even a week or 3 longer.

I haven't forgotten about this though...I will update it when I get some rounds fired.

[Sure Shot Mc Gee]

IMHO: Never cared to own a 7mm anything.
Historical fact: 270 cartridge has a 34 year head start over the 280 or 7mm Express or 280 again or what ever its called and its cousins also> (280-IM.) Although a 280 IM has a substantial increase in ballistics's over the venerable 270. One thing to keep in mind. 270 is, and always will be one of those cartridges that its so called competition try as they may never quite measure up.

[Pathfinder45]

And to think, you could just go out and buy a nice 270 Winchester while you're waiting for the Nosler..... As I've probably mentioned elsewhere, my model 70 routinely goes to 3,000 fps with 150 Nosler Partitions. It's a beautiful rifle too with real Walnut. I'm sure the Nosler 280AI will be a solid performer too. I hope it's worth the wait and price. Let us know how it turns out. I think 160needs will wring out the most you can get out of it.