22" barrel for .280AI, how much of a handicap?

[wombat13]

I'm getting very interested in acquiring a rifle in .280AI. I see that Savage offers it in the Axis II. I have an Axis II in .25-06 that is an accurate rifle. The Axis II in .280AI weighs in at 6.3 lbs. I think it would be low cost (a little over $400) way to see how much I like .280AI in a lightweight rifle and based on my limited experience is likely to be accurate.

The downside is that it has only a 22" barrel. I would prefer a 24", but given the low price, maybe it's worth it. How much of a handicap is a 22" barrel in .280AI?

I calculated the "expansion ratio", i.e., the case volume divided by bore area, and it is about the same as .257 roberts +P or 6.5x55 swede.

 

[jmr40]

I can't say specifically about that cartridge, but based on the ones I've seen data on, plus my own experiences it will be a lot less than most people think. The only reliable way to know is to start with a longish barrel, chronograph the ammo, cut the same barrel and chronograph it again. I've never seen any cartridge lose over 25-30 fps/inch and most are closer to 10-15 fps/inch when that is done.

Where you make the cut matters too. If you start with a 26" or 28" barrel you see very small drops in velocity per inch until you get to around 22"-20". Below 22"- 20" and the velocity drops are much greater per inch. There is a reason 22"-24" is the most common. That is pretty near the sweet spot. Going longer gains very little, but much shorter and you do start to see significant loss of velocity

When you start comparing rifle "A" to rifle "B" (even with the same barrel length) somewhere between 25-50 fps difference is normal and 100+ fps isn't unusual. I have 2 rifles in 30-06 with 22" barrels and the Winchester is always around 90 fps faster than the Remington. My Winchester is 130 fps faster than a hunting buddies 22" 30-06. I have a 20" barreled 308 that is faster than both of my 22" barreled 308's. You may find the 22" barreled Savage to be a tiny bit faster than another rifle with a 24" barrel, or it might be 150 fps slower. But it ain't the barrel length that will make the difference.

In other words you see much greater difference between different rifles than 2" of barrel makes. If you start comparing rifles with 20" barrels to rifles with 26" barrels then you start seeing meaningful differences. When deciding between 22" or 24" barrels how the rifles look and balance is really the determining factor

 

[Archie]

I understand AI is 'Ackley Improved' and I presume ".280" is the .280 Remington.
The .280 Remington seems to be an updated version of the 7x57mm Mauser. It is the same bullet diameter, therefore the same gamut of bullets. The case is a bit longer and is chambered in 'full strength' receivers, so the stats and probably ballistics are superior to the older 7x57mm round.
The AI version should be of greater powder capacity than the .280 Remington. So it should be capable of even greater velocity with the same weight bullets than the stock .280.

Back to the 7x57mm Mauser. That round has killed most all game on the planet. Including elephants measured in hundreds. I cannot imagine a .280 AI being incapable of most anything in the hands of a proficient rifleman.

As to your specific question: Probably not to any appreciable degree. If one seeks the fastest rifle (or something along that line) it may not be the fastest. For utility in practical matters, sounds suitable to me.

And I must applaud jmr40's comment as well. He makes very good points about comparing 'this gun' to 'that gun'.

 

[Varminterror]

Some barrels are fast and some are slow. But in general, longer barrels mean more dwell time under force, which translates to greater velocity - for a full pressure cartridge like 280AI, 2” of barrel would mean an expected difference around 60-80fps with the slow powders we typically use beneath heavy for caliber bullets. Not enough to make or break a hunting rifle.