Only 500-700 rounds? I'd forget about anything that burned barrels up that fast. I think the answer to this question is the 220 Howell. Here's some info. from the horse's mouth so to speak in regards to 220 howell vs. the 220 swift.
Re: Most accurate long range varminter? [Re: fryguy]
#16124 - 06/30/01 11:06 AM Edit Reply Quote Quick Reply
"On a quiet day, the Swift is difficult to beat, even way out there."
No longer true. The Swift is still as great a cartridge as it ever was, but now there's a bigger, stronger, and smarter kid in that family. There's now a .220 cartridge that was specifically designed to outdo the Swift, and it does exactly that. Its case capacity is about 29% greater than the Swift's, but it isn't intended for either the lighter bullets or the higher pressures of the Swift. It uses a 50% heavier bullet, with a larger charge of a slower powder.
It isn't a scaled-up Swift. It's more like a scaled-down .25-06.
The muzzle velocity of the factory (Remington) Swift with a 50-grain Hornady is (IIRC) 3,780 ft/sec, presumably at the SAAMI maximum pressure — about 60,000 lb/sq in. The muzzle velocity of the .220 Howell, with the 75-grain Hornady A-Max, loaded to the much gentler 50,000 lb/sq in. for longer barrel life and generally better performance, is about 3,500-3,600 ft/sec. At about 180-190 yards, the velocity of the 50-grain from the Swift and the 75-grain from the Howell is the same. Beyond that range, the 75-grain from the Howell is increasingly faster than the 50-grain from the Swift.
The 75-grain has a significantly higher ballistic coefficient than the 50-grain and is 50% heavier, so its trajectory, resistance to wind deflection, and delivered energy are far better than the Swift's 50-grain — or any other bullet at Swift velocities. The Swift, obviously, can't drive the 75-grain at anything near the velocity that it gets routinely from the 29% larger case.
Designed around the 75-grain Hornady A-Max (or 80-grain Berger or Sierra) and IMR-7828, the .220 Howell turns out to be at its best with IMR-7828 or Ramshot Magnum (formerly "Big Boy") powders. IMR-4831, for example, is too fast.
The grand old Swift stands up to the .220 Howell pretty well at short range (except in delivered energy) but rapidly falls behind at long ranges.
And remember, the .220 Howell outperforms the Swift at peak pressures 10,000 lb/sq in. LOWER than the Swift's — for longer case and barrel life and usually better round-to-round consistency. Your rifle is more likely to be accurate at 50,000 lb/sq in. than at 60,000 lb/sq in.
BTW, although this cartridge bears my name (because I designed it), I have not, do not, and will not ever get a cent out of it. My satisfaction with my .220 Howell rifles and your satisfaction with yours are my only returns on this cartridge.
Which suits me just fine Re: Most accurate long range varminter? [Re: Eagleye]
#16127 - 06/30/01 09:48 PM Edit Reply Quote Quick Reply
"Since the 220 Howell is, at least for now, a handloaders proposition, comparing the rather anemic 50 gr Swift factory load is not really fair."
--- Yes, it is fair, since the factory Swift load is an established and published safe standard for comparison. It is indicative of what SAAMI maximum pressures produce with a 50-grain bullet in the Swift. As for its being "a handloader's proposition for now," two points:
(a) Any varmint cartridge that gets much use is sooner or later a handloader's proposition, even though factory ammo is available.
(b) The .220 Howell is a factory cartridge. I prefer handloading it, and I believe that most who shoot it are also handloaders, but it IS, indeed, a factory-loaded cartridge.
"Any 26" Swift I have ever owned will easily break 4000 FPS within safe pressure limits with the 50 grainer."
--- I must contest this claim. Loads that produce 4,000 ft/sec are NOT within safe pressure limits. Also, loads that depend on maximum and over-maximum pressures erode barrels MUCH faster. In the .224 barrel, these pressures erode throats 8.9% faster than the same pressures in a .244 barrel. Longer barrel life is one of the basic reasons for the design of the .220 Howell — to use pressures no higher than about 50,000 lb/sq in. instead of the 60,000 lb/sq in. of the SAAMI maximums and the 70,000 lb/sq in. (and higher) of the handloads that produce 4,000 ft/sec.
"... those long bullets in the Howell require very quick twists to stabilize,..."
True but not a liability. Nine inches is about right.
"... which often create rather quick pressure rises if one isn't careful with load development."
--- Not at all. With the powders best suited to the .220 Howell, the pressure curves rise less steeply, peak more gradually and longer, and diminish less abruptly. With the faster powders in the Swift, the pressure curve rises more steeply, peaks sharply, then drains rapidly. Besides, with the pressure peak 10,000 lb/sq in. lower than the Swift's, there's a much wider margin of safety above the Howell's curve, enough to absorb any weird peak much more safely than would be the case with the Swift.
"Will this ever become a factory cartridge, Ken?"
--- It already is. Always has been, from Day One. Rifles, cases (headstamped "220 Howell"), ammo, and dies are available from American Hunting Rifles (AHR) — see
http://www.hunting-rifles.com — but I prefer to make my own brass from new Winchester .25-06 cases. Reamers are available from a number of companies (Pacific Precision Grinding and Manson Reamers, to name two, and I can provide dimensioned drawings to any other reamer-maker at no cost on request), and a number of gun-makers are already making .220 Howell rifles and rebarreling customers' rifles for this cartridge.
I planned and designed this cartridge very carefully, relying on interior-ballistics basics not usually considered by cartridge designers these days. I designed it to be exactly what it is, and fortunately, it works exactly as I planned it. Unfortunately for shooters who are just becoming aware of it, its interior-ballistics basics are not familiar, not obvious, not repeatedly printed in the sporting-arms literature. So it defies a lot of "conventional wisdom" that's based on other criteria (much of it wrong to begin with). Yet it's very simple, very straight-forward, once you get past the haze of "conventional wisdom."
