I have been reading articles about wildcats and wildcatters for years and years. A wildcat is a cartridge that is not commercially available and supposedly fills some previously unfilled niche in the shooting sports. A wildcatter is a person who develops wildcats. The technical savvy required for this kind of work seems to make it the most sophisticated and enviable of shooting hardware activities.
The utility of wildcatting is shown by the fact that many of our most useful cartridges began their lives as wildcats. The .22-250 is one of the best examples, and all of the cartridges based on the .308 Win case (.243, .260, 7/08, .358) began as wildcats. The ol’ .308 certainly sired a useful family. One of the latest flare-ups of wildcatting occurred a few years ago when the .300 Remington Ultramag appeared. The catters rushed in to neck it up, to .375, for instance, and they had to hurry because they all knew Remington was going to do this anyway. But it was all fun.
According to what I have read, you must be super smart, well-heeled, and very persuasive to be a wildcatter. First of all, you need a good idea for a new cartridge. Then, you must be able to call up people who make chamber reamers and gauges, give them the data, and get them to quickly send said materials to your custom gunmaker, with whom you have previously decided upon the action to be used, the barrel, the stock material and design, etc., etc., etc. If questions arise, you need to be able to call experts at RCBS, Hornady, etc., for advice and of course, they will always give it freely. Lastly, you must have the charisma and the moola to get all of this done and shipped to you in a reasonable amount of time (soon).
If you can manage all of this, then you are a very respected and busy gun nut and writer. It is likely, therefore, that the finished product will be delivered a day or two before you leave on your long-scheduled African safari for plains game. Or perhaps you have an invitation to a factory-sponsored varmint shoot for gun journalists to try out new guns and ammo, and it starts in a day or two. Whatever the reason, you only have time to shoot a few three-shot groups with your new piece. Results will be encouraging, and you will promise to wring it out completely upon your return and make a full report at a later date. You will certainly do that and results will be mighty fine. Reports of a wildcat being a real dog are rare in gun literature.
Getting an Idea
Considering the above, I always thought that wildcatting was beyond my reach. I had no ideas, not much technical knowhow, and I doubted that I could even get the people I would need on the phone, much less get them to send me the stuff I wanted in a reasonable amount of time. Anyhow, it seemed that everything in wildcatting had already been done. Take a look at P. O. Ackley’s Handbook for Shooter’s and Reloaders (1) and you might be convinced of that. Ackley is a little dated, so you could also look in Wolfe Publishing’s Wildcat Cartridges (2). These references list a ton of cartridges that blanket the field. Pretty hard to find a niche for a new round.
Then one day I was loading .30-30’s for some shooting experiment and my simple brain thought “Wow, this hull sure has a long neck.” And a little later, “The .223 Remington has no neck at all, and it seems to perform very well.” Then it hit me: I could make my own wildcat by shortening the neck of the .30 WCF. Hey, if you can get a wildcat by changing the diameter of a case neck, and that has been done a lot with the .30-30, why wouldn’t changing the neck length also qualify? The afore-mentioned P. O. Ackley generated a whole series of “improved” cartridges just by enlarging chambers and blowing out the shoulders of existing cartridges. Man! I could do all of the work myself, and I wouldn’t even need a chamber reamer, or any rifle modifications!
I rushed to the shop, got out some new cases, sorted them by weight and deburred the flash holes. Then I got a cutting wheel in my Dremel Tool and went to work. I lopped off a chunk of neck on a number of cases and trimmed them all to the same length. The normal length of a sized .30-30 is about 2.040”. In no time at all, I had
thirty cases measuring 1.823”, more than 0.20” of case neck gone. Now all I needed was a name for this creation. A wildcat must have a colorful name in order to attract attention and invite use by others. Some catters have attached their names, as in “.219 Donaldson,” to their cartridge creations, but I didn’t think I wanted my name associated with this one. I thought about .30 WNN (Winchester No Neck) but finally settled on .30 WCC (Winchester CircumCised). The photo shows the results with Sierra 170-gr flat noses loaded to the same OAL, about 0.10” longer than factory loads. The WCC loading looks precarious, but the bullet base is actually at the bottom of the neck.
All Kidding Aside
OK, perhaps you have guessed by now, this report is really about neck length, not wildcatting. For some time, my experience has been, other things being equal, long case necks give better shooting results than short case necks, meaning that the performance of a cartridge with a long case neck is less sensitive to variations in chamber length and bullet seating depth. This is certainly not a new idea. Cast bullet shooters have long espoused the advantages of long case necks in insuring good bullet support and alignment That said, my current opinion is based on certain anecdotal evidence in my personal shooting experience that I will now relate.
The conventional wisdom maintains that best accuracy is obtained when bullets are seated so as to be very close to the rifling lands when chambered. Thus, accuracy seekers will seat bullets to be within a few thousandths of an inch from the lands. Some shooters get good results when bullets are seated so as to touch the lands, and this concept was known to fine target shooters of yore.
Over a period of years, I have had several rifles with long chambers. When I say “long chamber” I am talking entirely about the throat, that part of the chamber that holds the neck of the cartridge. If you have a chamber which is too long in the body of the cartridge, you have a very dangerous problem with headspace that can only be corrected by serious gunsmithing. On the other hand, a long throat, or “free bore,” as it is sometimes called, does not cause a dangerous situation.
My long-throated beauties often shot well with bullets seated to factory specs, which put the bullets nowhere near the lands. These mavericks all used long-necked cartridges and included a Ruger #3 .22 Hornet, A Remington 700 .222 Remington, a Savage 340 .30-30 Win, and a couple of Springfield Krag .30-40’s. The .222’s chamber was so long that if I were to seat a bullet within .003” of the lands, its little butt would not be in the cartridge case at all. I don’t know why it was cut this way. After singing several choruses of “How Could They Do This to Me?” I decided just to shoot it with rounds meeting factory specs for OA length. Turns out the rifle was not a world beater, but it shot very well, indeed.
The chamber of the Savage 340 measured 2.838” using a Stony Point OAL gauge and a Sierra 150-gr flat nose. Factory .30-30’s are loaded to an OAL of 2.500 to 2.540”, which puts the bullet about 0.30” off the lands in my ol’ Savage! In accuracy language, that is way, way too short a load. Nevertheless, this 340 has shot many groups of 1.5 MOA or less with factory loads. In handloading, the long neck of the .30-30 allows bullets to be seated to a much longer OAL, but still never close to a few thousandths off the lands. I have fired hundreds of groups with handloads in this rifle, and its accuracy has been consistently good, considering, of course, that it is a low-cost hunting sporter, and not a target rifle.
Before going further, it would be helpful to have a more quantitative approach to neck length. I want to define a parameter called the “Neck Length Factor” (NLF) as a good way for expressing this neck characteristic. The definition is
NLF = neck length / bore diameter.
This gives a number which expresses the neck length characteristic of any cartridge, in a manner that is independent of the caliber of the round. For calculation of NLF, one can use cartridge dimensions given in loading manuals. Thus, for the .30-06,
NLF = 0.375” / 0.308” = 1.22
The NLF values for some popular cartridges are given in the following table.
Long necks: NLF Short necks: NLF
.22 Hornet 1.68 .223 Rem 0.86
.222 Rem 1.35 .22-250 1.06
6 mm Rem 1.40 .243 Win 0.95
.30-30 Win 1.52 .308 Win 0.95
.30-40 Krag 1.54 7 mm Mag 0.92
.30-06 Spfld 1.22 .30 WCC 0.85
In general, older cartridges have longer necks, with an NLF of about 1.5, and newer cartridges have shorter ones, an NLF of 1.0 or less. The .22 Hornet is the champion long neck and the .223 Remington is the king of shorties. Note that I am not saying that long-necked cartridges are, in general, more accurate than short-necked cartridges. Accuracy depends on many factors. My thesis is that a long neck might aid its cartridge in providing consistent accuracy performance when varying chamber dimensions are encountered in mass-produced sporting arms.
At the Range
I had the goods. I had a rifle with a long throat and I had cases of two neck lengths. I had the standard .30-30, NLF = 1.52, and my new wildcat, the .30 WCC, NLF = 0.85. I loaded them using Federal match primers and W748 powder behind Sierra
170-grain flat-nosed bullets. Since I had no African safari planned and no invitations to factory-sponsored varmint shoots, I had nothing to do but take my
goods to the range. I fired 28 four-shot groups at 50 yds with the .30 WCF and 28 four-shot groups at 50 yds with the .30 WCC. I fired them in alternating fashion, a long-neck group, then a short-neck group, so I ended up with 28 pairs of groups, each containing a long- and a short-neck group. The long-neck group was smaller than the short-neck group in 22 of the 28 group pairs. Overall accuracy results are summarized in Table 1. The values given first are mean values of the actual center-to-center group measurements at 50 yds. SD is the standard deviation of the mean. MOA, minutes of angle, is simply double the group mean size. Figure 2 shows two pairs of these groups that support the hypothesis. For all groups I also measured and included the best three of the four shots. Why? Because I like to. The threes, of course, are always smaller and that feels good. More importantly, the comparison of three- and four-shot group means shows how much I would err in evaluating accuracy with groups of only three shots, and that was sobering.
Table 1 – Mean Extreme Spread Center-to-Center – 28 4-shot groups
All Four Shots Best Three/Four
Long Necks Short Necks Long Necks Short Necks
0.542” 0.752” 0.313” 0.460”
SD 0.162” SD 0.225” SD 0.119” SD 0.182”
1.08 MOA 1.50 MOA 0.63 MOA 0.92 MOA
The groups of the short-neck loads are about 50% larger than those of the long necks.
Some additional data:
Long Necks Short Necks
Smallest group 0.209” 0.366”
Largest Group 0.939” 1.295”
Size of spread 0.739” 0.929”
Experimental shooting always involves making decisions about the significance of the data. In many reports of group results with factory loads or handloads, conclusions are made on the basis of a number of groups that is really too small to be statistically reliable. In the present case, we want to know if the smaller size of the long-neck groups is really due to the cartridge condition, or was it simply chance? In statistical language, is the difference in the means of the two sets of groups a real difference?
Seat-of-the-Pants (SOTP) statistics tells me that the long-neck cartridges are more accurate. If the long-necks shoot smaller groups if 22 out of 28 pairs, forget formal calculations, that fact, along with the difference in average groups sizes, is good enough for me. It seems to me that SOTP works pretty well for experienced shooters, but that is true only when they shoot enough(?) groups. If I had shot only four pairs of groups, with the long-necks shooting smaller in three of them, I could arrive at the same opinion, but I would be on much shakier ground.
For a slightly more formal treatment, let us look at it this way. Forgetting pairing, consider the two sets of 28 groups each. The SD values show that there is quite a bit of variation in the sizes of the groups.
Therefore, some of the better groups of the short necks will be smaller than some of the poorer groups of the long necks. That is, the two sets of group sizes overlap. In any comparison of two sets, the greater the overlap, and the fewer the number of groups shot, the less reliable will be any conclusions based on the mean values, and the mean values may not be really different.
From my data for the two sets of groups I will select the following:
Five smallest groups, short necks: 0.366, 0.448, 0.475, 0.542, 0.545 – Mean 0.475”
Five largest groups, long necks: 0.939, 0.840, 0.740, 0.694, 0.683 – Mean 0.779”
Looking at these mean values one would would be tempted to conclude that the short-neck rounds shoot better by about 0.3” (0.6 MOA)! If these ten groups were all that had been fired, SOTP would suggest that short necks are more accurate than long necks.
As part of the larger set, these ten groups indicate a fair degree of overlap, but hold on. In my case, there are 23 remaining groups in each neck length set. These remaining groups show an even greater performance difference because the poorest groups have been eliminated from the long necks and the best groups have been eliminated from the short necks. Follow? The numbers are:
Mean value, 23 long-neck groups: 0.491” SD = 0.121
Mean value, 23 short-neck groups: 0.815” SD = 0.197
From this it seems quite certain: Long-neck rounds are more accurate than short-neck rounds, but I must hasten to add that this is true for this particular rifle. I feel that similar results would be obtained with other rifles, but a generalization would require more work, and a lot of it.
Accuracy is emphasized in this report, but I also found a small but persistent difference in the velocity of rounds in the two neck length categories. The short necks always gave slightly higher (30-40 fps) velocity but I did not gather enough velocity data to show that this is statistically sound. It put a smile on my face, however, to see that the higher velocity we wildcatters are always after did show up.
1) Ackley, Parker O., Handbook for Shooters and Reloaders, Plaza Publishing,1848 West 2300 South, Salt Lake City, UT (1962)
2) Wildcat Cartridges Combo Edition, Wolfe Publishing Company, 6471 Airpark Drive, Prescott, AZ (1992)