NEW SERIES ON IMPROVED CARTRIDGES....
The .223 IMP
paco
I like many of you, probably have read many times that Improved cartridge cases don’t really give enough additional performance to make them worth while. Then usually figures are bandied-about that there is only 2 or 3% more velocity.. and the cost of reamers and or gunsmithing, new dies... etc... etc...all add up to ‘not worth the effort and cost’.
Since I have a number of Improved chamberings in my rifles, I thought I would give the facts as I see them. But I will say first, I am partial to some Improved chamberings. Also there a few I don’t particularly like, we will explore those also. We start off the series with one I do like, and I like it very much... in fact it is one of those that is usually panned because it ‘doesn’t give enough added velocity to warrant the cost.!’
Let me say up front and I will probably repeat it many times thru the series... velocity isn’t always the main indicator for improving a chamber. One of the first things critics usually leave out about improved cartridges... increased velocity or not ....the sharp shoulders immediately bring about an efficiency not in the standard cartridge shape. Look at the new chamberings Winchester and Remington have brought out.. All with much sharper shoulder shapes then in the past. Industry is learning that efficient case shape not only burns powder much better, it improves potential accuracy.
I like long range shooting. Not so much long range hunting, because I like to hunt with handguns and leveraction rifles... but long range target shooting. In 1970 at the Richmond Virginia Gun Range, we had a centerfire NRA sponsored long range rifle contest. Over thirty years now so I forget all the specifics, but the last stage was at 500 yards. The range had very tall trees up both sides of the 500 yards range. And wind was not a factor that day.... I remember that because I chose to use an M16 .223 chambering.
There was a lot of laughter about the rifle because most who were never in the military at the time, didn’t really know the potential of the rifle or the cartridge. And other contestants were calling it a Mattel, a military plastic and stamped parts rifle... nonsense like that. It was at the 200 yard off hand stage that the grumbling started. Since I shot a perfect score to that point. But wiser heads among the click of shooters that thought they owned long range shooting, were telling their brothers "just wait for the 500 yard off hand...those little bullets won’t even make it to the target." Junk like that.....
In the prone, then the kneeling stage I dropped one shot into the 9 ring. In the off hand stage I dropped another. Out of a possible 600 points I came in with 598.... the protests were all over the place. Several shooters paid the dollar fee for official protests to the NRA, that the rifle wasn’t sanctioned by the NRA for rifle contests.....
Several days later the NRA response was simple... it was sanctioned and in fact a U.S. Army officer had won the Camp Perry matches with an M16 that year. I am the first to say I had a good deal of luck that day, especially with no wind... But all this to say that the little .223 can be a fun long range shooter at inanimate targets. And of course for small vermin it is very good even at long range. The .222 was always the benchrest darling for accuracy. And the .223 has always had bad press in that it never seems to stack up in accuracy against the .222, but think for a moment. Because the rifles being built for benchrest shooting are built very carefully with fine chambering and .222 is always chosen over .223. The only rifles to compare usually against the .222 benchresters is off the shelf varmint and heavy barrel types. I choose to turn the Howa into a benchrest type since I was going to re-chamber it. Not that I was going into that very exacting sport, I just wanted to squeeze ever ounce of accuracy out of the new chambering.
The question always comes up, what is long range. Personally for me it is anything over 300 yards... certainly 500 yards is a long way out there.
I fell into a deal for a Howa Rifle chambered for .223 a while back. It had some things about it I didn’t like. The synthetic stock was fine... it just had too long of a pull for me. Shortening was easy... the barrel was ridiculous for a .223 at 26 inches long. Four+ inches fell off the chamber and muzzle ends real quick. Being a bull barrel it is now very stiff. Before the operation it should have shot rings around most other standard rifles I have. After all it was supposed to be a bull barrel varmint rifle.
Most would think that 3/4ths of an inch at 100 yards is very good accuracy. And it is, but not for a bull barrel varmint rifle. Frank Wells one of the country’s premier rifle makers had to help me from this point. That barrel would not break, and come off the action. In fact Frank wound up buying new and larger equipment to get it off. We then took almost half the existing chamber off, and re-chambered it with a custom .223 Ackley 40 degree Improved reamer, to very close benchrest tolerances.
Using the 55gr. CT. Ballistic Silvertip Nosler bullet over 27 grains of Benchmark, standard Federal primers in Remington nickel cases, that have been previously fire formed.... 5 go into one ragged little hole 1/3rd of an inch at 100 yards. The velocity clocks in at an average 5 shots on a cool day at 3498 fps. Remember these figures are from an improved case/chambering.... I wouldn’t try 27 grains of Benchmark in a standard .223 chambering. I know that before in the old chamber, 24.5 grains was tops at 3332 fps. Benchmark by the way consistently gives higher velocities than most other powders for me in the .223 type cases...
For a coyote bullet and load the Hornady 60 gr V-Max (shown in the photo in the improved cases) over 25 grains of Benchmark again, break 3250 fps and hover around a half inch at 100 yards. Surprisingly H335 at 26.5 grains gave almost the same velocity and accuracy. If I couldn’t get Benchmark I would use H335 and never look back.
I was disappointed with ReL#15 the velocity was up there but the accuracy was just less than an inch at 100 yards.
The Remington cases fire formed hold two grains more water than the standard case. The Remington cases weigh out the lightest of all tried... military ‘68, Winchester, and Federal... meaning they have more internal space.
I have now fired 20 of these Remington cases with top loads, 30 times each without stretching. Still primer pockets tight, and ready to go for another 30 loadings at least. And at the price of brass today, that’s a real savings.
If you are going to have any chambering redone to a improved shape, two things. Make sure the reamer is absolutely flawless... and always have the barrel turned back several turns before re-chambering. And it takes a good gunsmith not a parts changer to cut a fine chamber.... and number two have the muzzle re-crowned any one of several target shapes. Personally I like a very shallow crown. What’s important is the muzzle’s bore hole is perfectly round and even.... not some fancy shape.
So is the .223 worth improving... is the rifle you are going to improve worth it? Do you have someone who has a new reamer that has never been sharpened, and do you have a gunsmith that has put together target rifles before? If so, that’s half the work.... the other half is finding the right loads once the job is done.... but of course that’s the fun part....paco 2/04
