.250 Ackley Improved

gobigorgohome said:
I dis a massive ammount of research and looking as I wanted a new deer gun. Although the 270 is already perfect, the 250 savage I think is the greatest short action, low recoil caliber ever. My dream is to build one on a savage 99. But a year into my search and I haven't found a perfect gun to turn into a 250 ai. And out of all the ai calibers, the 250 sav can add up to 300 fps and I think is very worth while. I'm currently searching for a left handed rem 700 cdl in 308, 243 or 22-250 to build into a 250 ai. I don't think you can go wrong. You have mighty fine taste in calibers!
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I saw your WTB ad; unfortunately my remaining 99's are 1:14 twist. Those 1:10's are elusive critters! And Savage chambered the 14 and 16 in .250 for a couple years but no longer, and I don't know that they made any lefties. Savage does custom-chamber rifles, as far as I know, and you may be able to get a Model 14 or Model 16 in .250 Savage from them and AI it.
Good luck on your search!
 
As with most AI cartridges, performance gains are primarily the result of loading to higher pressures. Loaded to the same pressure (and there is absolutely no reason they cannot be), the parent cartridges are usually within 50 -75 fps of the "Improved" versions. Standard 250/3000's are capable of driving 100 grain bullets to 3000fps or slightly more. The standard 257 Roberts will exceed 3100 with 100's (This isn't too surprising. After all, the 6mm Remington uses the same case to do this with 100 grains bullets.) The huge gains realized with the AI'd cartridges are generally the result of comparing the slowest factory offering to a max pressure loading in the AI.
Even cartridges which are radically altered by the change don't achieve quite the gains which many think they do. I can drive 165 grain bullets to 2900 from my 303 EPPS but I can hit 2800 from the standard 303 (NOT from a Lee Enfield, mind you) and the Epps gains at least 10% in case capacity when fireforming is complete. So, while the Epps can achieve a 350 fps gain with 180's, over the factory 303, when loaded to the same pressures, the gain is nothing like that.
 
I hemmed and hawed for quite some time, and finally ended up getting the rifle Ackley-ized.
Big thanks to Dennis (Guntech) for doing the job, and for the quick turnaround time.
I have started load development and I am very pleased thus far.

Some people questioned why I might want to do this conversion. Well, I have been in love with the .257 Roberts since forever, but have found it difficult find a combo of rifle and load that is consistently accurate. My experience with the .250 Savage has been that it is much easier for me to get good results with. I have owned half a dozen rifles in each chambering. So ideally, I was hoping to get Roberts velocities and capability in an easy-to-work-with cartridge.
I had a good accurate .250 Savage bolt rifle; I just wanted a bit more velocity.

A little background: I just fired some .250-3000 fadtory ammo in a 22-inch barrel. Remington and Imperial 100-grain loads averaged about 2775 fps; Winchester 100 Silvertips were a bit slower at about 2725 fps.
My stiffest 100-grain .250-3000 handloads averaged about 2950 fps. Accuracy was about MOA, even with premium bullets including Swift Sciroccos and A-Frames and Barnes TSX.

So far, with little testing, I have Ackley handloads shooting the 100 Sierra BT into about 1.25" at 100 yards (3-shot groups) at an average velocity of 3120 fps and the Nosler 100 Ballistic tip just under MOA, at an average velocity of 3130 fps.

The real surprise came with heavy bullet loads. Loads using H4831SC and the 120 Speer flatbase grouped between 0.500" and 0.800" at a velocity of 3010 fps. No pressure signs.

So what did I gain? Well, I did gain the extra couple hundred fps I wanted to feel more confident in the rifle. Also, my Ackley loads have accounted for the best groups out of the rifle to date, though that may be coincidence and human error.

The downside to me is that if I ever get tired of handloading I will lose the gains I've made, but that's life.

For those concerned about case availability, I have about 300 rounds of factory ammo which should supply me for some time, or I can neck up .22-250 cases. I also found another 300 rounds of ammo I will buy as money allows. I don't intend to shoot a zillion rounds from this rifle; I wanted it as practical hunter, which it is. It's a Savage 16 Weather Warrior with detach mag, and a Burris Fullfield 3-9 scope. It should bring the venison home for as long as I care to hunt.
 
Well there is one pressure sign I can see...3100+fps with 100gr pill and 3000+fps with 120's.
Someone should plug this into quickload to see what it spits out for pressure.
 
Kilo Charlie said:
The real surprise came with heavy bullet loads. Loads using H4831SC and the 120 Speer flatbase grouped between 0.500" and 0.800" at a velocity of 3010 fps. No pressure signs.
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..... WOW!! That's a rockin' load. I'd be looking high and low for a good ( read lifetime ) supply of those Speers.

Some of the Speer line is getting hard to find.
 
Hitzy said:
Well there is one pressure sign I can see...3100+fps with 100gr pill and 3000+fps with 120's.
Someone should plug this into quickload to see what it spits out for pressure.
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I was a bit taken aback, but think about it. People routinely handload the .250 Savage to nearly 3000 fps. An extra couple hundred fps in the Ackley shouldn't be a huge surprise. Also, I'm using a standard loading recipe the 120; lots of H4831. Normally upper limit loads are difficult with this powder because you run out of case capacity. Gaining that extra 3-odd grains of capacity really helps. Mind you, I would certainly appreciate if anyone wanted to run this in Quickload as I don't know how.
I do know that the .250 Ackley is expected to perform about like a .257 Roberts, some say like the Roberts AI, so I don't see anything ominous or unusual about these velocities. If this were a standard . 250 Savage I'd be agog.
 
SuperCub said:
..... WOW!! That's a rockin' load. I'd be looking high and low for a good ( read lifetime ) supply of those Speers.

Some of the Speer line is getting hard to find.
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I have about 140 or so. I also want to try a bullet that has never worked for me in a .257 Roberts; the 117 SST. I've had reasonable accuracy with regular Hornady 117's, be it boattail, flatbase or roundnose, but never the SST, a bullet I LOVE in the .280 Rem, the .300 Savage and the .30-06. And even though I don't hunt varmints or predators, I'm going to see what the .250 AI does with 75-grain and 87-grain bullets.
 
Kilo Charlie said:
I was a bit taken aback, but think about it. People routinely handload the .250 Savage to nearly 3000 fps. An extra couple hundred fps in the Ackley shouldn't be a huge surprise. Also, I'm using a standard loading recipe the 120; lots of H4831. Normally upper limit loads are difficult with this powder because you run out of case capacity. Gaining that extra 3-odd grains of capacity really helps. Mind you, I would certainly appreciate if anyone wanted to run this in Quickload as I don't know how.
I do know that the .250 Ackley is expected to perform about like a .257 Roberts, some say like the Roberts AI, so I don't see anything ominous or unusual about these velocities. If this were a standard . 250 Savage I'd be agog.
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You appear to be claiming that "3 extra grs shouldn't surprise anyone with an extra 200 fps from a 250 Ackley". I can throw around loads that get an extra 300 fps with the same amount (but I won't), so I will agree that I'm not surprised.

There's almost 10.0 grs more capacity in the 257 Roberts than the 250 Savage, so that means that there are about 7.0 more grains than in your 250 Ackley - right?

How then do you suppose you're getting equal MV's? There's not need for anyone to run Quickload to answer that.

I could be missing something. What was your load in the 250 Ackley that produced 3010 fps with a 120 gr bullet? I didn't think you could cram enough H4831SC into the case to get that MV.
 
Andy said:
You appear to be claiming that "3 extra grs shouldn't surprise anyone with an extra 200 fps from a 250 Ackley". I can throw around loads that get an extra 300 fps with the same amount (but I won't), so I will agree that I'm not surprised.

There's almost 10.0 grs more capacity in the 257 Roberts than the 250 Savage, so that means that there are about 7.0 more grains than in your 250 Ackley - right?

How then do you suppose you're getting equal MV's? There's not need for anyone to run Quickload to answer that.

I could be missing something. What was your load in the 250 Ackley that produced 3010 fps with a 120 gr bullet? I didn't think you could cram enough H4831SC into the case to get that MV.
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Could not agree more. Andy is telling it like it is. D.
 
I should have been more specific.
I don't see any pressure signs that concern me. I'm getting velocities pretty much on par with what I expected with 100-grain bullets and a little more than I expected with the 120, with no accompanying signs of excess pressure, ie no blown or cratered or backed-out primers. No bolt handle or extraction stickiness whatsoever. No signs of incipient case-head failure.
I am certainly above recommended safe pressures in a Savage 1899, but I am using a modern bolt rifle.
 
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