Two HOT .224 cartridges

[Ken Howell]

A couple of my friends shoot and are quite happy with the .22-6mm Remington, a cartridge that's very nearly (but not quite) the same as my .220 Howell. They've both asked me to compare some ballistics of our two cartridges. Somebody in one of these forums asked the same thing (I can't remember which board). Anyway, for anybody who cares, here are some ways that they compare.

Since they have very nearly the same case capacity and use the same bullets, I settled on one bullet (the 75-grain Hornady A-Max, which all three of us like) and one velocity (3,500 ft/sec) for my first comparison — to see (a) which powders and charges would propel the same bullet at the same velocity in each case and (b) the peak pressure resulting from each charge in each case.

In the .22-6mm Remington (gross case capacity 56.6 grains of water)
52.0 gr —— Ramshot Big Boy —— 56,540 lb/sq in.
48.4 gr —— IMR 7828 —— 56,896 lb/sq in.
49.0 gr —— Vihtavuori N560 —— 54,994 lb/sq in.

In the .220 Howell (gross case capacity 61.2 grains of water)
54.6 gr —— Ramshot Big Boy —— 50,465 lb/sq in.
50.7 gr —— IMR 7828 —— 51,299 lb/sq in.
51.3 gr —— Vihtavuori N560 —— 49,835 lb/sq in.

For my second comparison, I used the same bullet and the same three powders to see which charge of each powder would produce which velocities at the typical SAAMI maximum peak pressure of 60,000 lb/sq in.

In the .22-6mm Remington
52.8 gr —— Ramshot Big Boy —— 3,563 ft/sec
47.9 gr —— IMR 7828 —— 3,459 ft/sec
50.2 gr —— Vihtavuori N560 —— 3,596 ft/sec.

In the .220 Howell
56.6 gr —— Ramshot Big Boy —— 3,766 ft/sec
51.1 gr —— IMR 7828 —— 3,631 ft/sec
53.8 gr —— Vihtavuori N560 —— 3,794 ft/sec

Once again, for my third comparison, I used the same bullet and the same three powders to see which charge of each powder would produce which velocities at the maximum peak pressure of 50,000 lb/sq in. — the pressure maximum that I prefer.

In the .22-6mm Remington
50.4 gr —— Ramshot Big Boy —— 3,368 ft/sec
46.6 gr —— IMR 7828 —— 3,358 ft/sec
47.6 gr —— Vihtavuori N560 —— 3,394 ft/sec.

In the .220 Howell
53..9 gr —— Ramshot Big Boy —— 3,549 ft/sec
49.8 gr —— IMR 7828 —— 3,531 ft/sec
50.9 gr —— Vihtavuori N560 —— 3,570 ft/sec

All these figures are results from the same classic lumped-parameter equations, so any built-in calculation error in these equations applies equally to all the loads I've listed, leaving these comparisons of the two cartridges valid.

 

[Ken Howell]

I goofed.

Should've gone to bed earlier that night. Yawning apparently lets air into the brain.

The first comparison — both cartridges at 3,500 ft/sec — should read thus:

This part's right:
> In the .22-6mm Remington (gross case capacity 56.6 grains of water)
> 52.0 gr -- Ramshot Big Boy -- 56,540 lb/sq in.
> 48.4 gr -- IMR 7828 -- 56,896 lb/sq in.
> 49.0 gr -- Vihtavuori N560 -- 54,994 lb/sq in.

The second part should've been
In the .220 Howell (gross case capacity 61.2 grains of water)
53.3 gr —— Ramshot Big Boy —— 47,978 lb/sq in.
49.4 gr —— IMR 7828 —— 49,708 lb/sq in.
50.0 gr —— Vihtavuori N560 —— 47,225 lb/sq in.

instead of
> 54.6 gr -- Ramshot Big Boy -- 50,465 lb/sq in.
> 50.7 gr -- IMR 7828 -- 51,299 lb/sq in.
> 51.3 gr -- Vihtavuori N560 -- 49,835 lb/sq in.

 

[WDSWIFT]

Ken, what size groups do these 2 rifles produce at 100 or 200yds? Is the accuracy capability better in one than the other?
Does either one shoot 55-60gr bullets better than the other?
It is amazing to me that the Howell has that low of pressure.
Some where I heard that a short fat stack (cartridge) of powder is "always more accurate" than a tall slender one. I have my own opinion on this. How would you respond to that statement? WD.

 

[Ken Howell]

"... what size groups do these 2 rifles produce at 100 or 200yds? Is the accuracy capability better in one than the other?"

Accuracy depends more on the rifle than on the cartridge. The .22-6mm and .220 Howell rifles that my friends and I have are one-holers. The accuracy potential is greater in one of my .220 Howell rifles than in the other, for example, because of their different barrels and how they're bedded — not because the .220 Howell is more or less accurate than the .220 Howell, obviously.

"Does either one shoot 55-60gr bullets better than the other?"

The whole point behind these two cartridges is to get away from the handicapped down-range performance of the lighter .224 bullets with their abominable ballistic coefficients. So nobody I know has retarded either cartridge with anything lighter than 75-grain bullets. My .220 with the seven-inch twist would handle 60-grain bullets all right, but the other — with the nine-inch twist — wouldn't do so well with anything shorter than the 75-grain bullets.

"It is amazing to me that the Howell has that low of pressure."

The "secret" is simple — just simple, basic interior ballistics applied to carefully engineered cartridge design, rather than a blind market-oriented drive for the highest muzzle velocity at whatever the cost.

Like any other cartridge, the .220 Howell can be loaded to any high pressure, from barely safe to devastatingly explosive. The "secret," with any cartridge, is to load it to moderate pressures. Any cartridge can be loaded to moderate pressures.

Any cartridge can be loaded to lower than the maximum SAFE pressures without great sacrifice in down-range performance, and sometimes down-range performance can even be improved with the right bullets. This fact is not new — it's just been obscured by the mad hype that has convinced shooters that all loads have to drive the bullets as fast as you can make 'em go, at peak pressures just a step this side of disaster.

"Some where I heard that a short fat stack (cartridge) of powder is "always more accurate" than a tall slender one. I have my own opinion on this. How would you respond to that statement?"

Some truth but overstated. The short, wide powder column has advantages over the long, slender powder column — but the difference between them is slighter and less significant than other differences in the rifles, shooters, circumstances, etc.

I have to just shake my head and mutter in wonder whenever I see shooters put primary emphasis on minor matters but scorn matters that they'd be better off emphasizing.

But let's not get off onto that hopeless cause!

 

[elmo]

Hey Ken, I've become interested in the Vihtavouri 500 series powders after reading about them in their website. They seem to be delivering high velocity with low pressure in your cartridges. Have you used them with .30 cal loads. I'm considering them for my .308 match loads and 30-06 hunting loads. How do they compare with the common powders that most folks use.

[This message has been edited by elmo (edited 03-10-2001).]

[This message has been edited by elmo (edited 03-10-2001).]

 

[WDSWIFT]

Ken, Your response to my questions either caught you on a bad day, or you misinterperted the point or intent (if you will) of them. Perhaps I didn't state the questions with enough background information so that you could see the point of my questions. For that I apologize.
Dealing with the general public on matters of Marketing and Public relations requires a careful and calculated transition between "The drawing board" and marketing success. Rule number one is: You don't belittle, or anger the customer.wd

 

[Ken Howell]

WD, you have completely stumped me. I don't have the foggiest idea what you're talking about. Neither "bad day," "belittle," "anger," nor "customer" applies to anything I can see or think of in this dialogue. "Marketing?" "Public relations?" I've never been involved in marketing except as a customer, and my only work in public relations was thirty years ago in the wood-products industry. You and I use English words but not in the same language.

[This message has been edited by Ken Howell (edited 03-11-2001).]

 

[Ken Howell]

Elmo, I haven't loaded any .30 cartridge, of any pedigree or lineage, with any powder, since long before the Vihtavuori powders showed up on these shores.