"STARBURST" KID
Dan and his boys from ND are tough customers. They expect "Starbursts" wherever the crosshair falls. With 40 years of varmint shootin' experience, Dan was a tough sell on a custom rifl e in a new caliber unique to one manufacturer.
After several thousand varmints dispatched, Dan is sold ! His James Calhoon custom CZ in the 19 BADGER is his best all around varmint rifl e. A TOTAL VARMINTING SYSTEM. He says it's a real "cutter"! Dan and his boys also value the personal service and expert technical support. Dan's 22 Mag, Fireball, 222, 223 and 204 are up for sale !
The 19 BADGER/CZ 527 Varminting System is the most pleasing, unexpectedly effective varmint rifl e you'll ever shoot!!
Once you own a James Calhoon fi nely tuned CZ rifl e in 19 caliber, you'll be "leavin' your other varmint rifl es in the safe."
Choose one of three 19 Caliber cartridges...
19 BADGER : Our newest cartridge. Velocity, range and accuracy of this tough, rimless case amazes shooters every time Possibly, it makes all other varmint rifl es optional (3725 ft/sec)
19 CALHOON (Hornet):
Adding 100 yards range, this Hornet on steroids is the ultimate squirrel/ gopher shooter
(3550 ft/sec)
19-223: The speediest and biggest of the 19 Calibers, “Full race” varmint cartridge.
(4000+ ft/sec)
Visit our entertaining Web Site or Call Us Discover our affordable, custom 19 Caliber CZ rifl es; Re-Barrel Kits; our full line of 19 Caliber accessories; and our Fine Shootin’ varmint bullets in 19, 20, & 22 caliber.
techniques. The Hornet does appear more picky than most other cartridges when it comes to developing accurate handloads but this should be consid- ered a challenge and an opportunity to learn something, rather than an obstacle. Those of you who shoot factory loads are on your own. I can only suggest you shoot all available loads and then select the most accurate – or take up handloading. Firearms chambered for the Hor-
net use rimmed cases; therefore head- space on the rim. In theory this is fine but in practice it can leave something to be desired. Two variables are the case and the rifle chamber. As I understand it, the thickness of rims on cases can vary from 0.055 thru 0.065 inch and chambers can have headspace measurements from 0.065 thru 0.072 inch. Everything is fine if the rim thickness and the chamber headspace dimension are within several thousandths of each other (assuming the rim thickness is the lesser of the two) but this is not always the case. I have measured the headspace
dimension of four Hornets and all were pretty much in the middle of the allowable tolerance range. This is as it should be. Cases are another matter. They average around the middle of their tolerance range but probably will use up most if not all of their tolerance range on a bag of 100. This is not as it should be and results in a headspace problem. Accuracy may be affected and case head separation may be of concern. One of the accuracy improving
techniques I adopted years ago for the Hornet was sorting cases by rim thick- ness. This was started to a large extent based on the findings of 22 rimfire shoot- ers who seem convinced that sorting by rim thickness greatly improves accuracy – and this is for rim thickness variations of only several thousandths of an inch. Based on the approximately 1,200 cases I have measured for the Hornet, rim thickness varies by 12 thousandths, which is three to four times the variation found by 22 rimfire shooters. It seems as though there’s gotta be a problem here. Being more specific, rim thickness
on the Hornet cases I have measured varied from 0.054 to 0.066 inch. How much, if any, would this variation af- fect accuracy and/or point of impact? Back in the 1990s, I made a couple of half-hearted attempts to determine
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4343 U.S Highway 87 Havre, MT 59501 (406) 395-4079
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Spring 2012
the answer to this question since sort- ing cases by rim thickness is about as exciting as watching grass grow. No firm conclusions were made. I ended up taking the easy way out and started sorting cases into groups having a rim thickness variation of not more than 0.003 inch – for example, from 0.060 to 0.063 inch. Additionally, all cases hav- ing rim thickness of 0.057 inch and less (approximately 2% of the total) were thrown away and all cases having rim thickness more than 0.064 inch (approxi- mately 3% of the total) were modified to have a rim thickness of 0.064 inch. These steps, I believed, took care of the accu- racy problem but did not eliminate the need to measure rim thickness. Lately, with the accuracy question starting to bug me and sorting by rim thickness with the addition of sorting these same cases by weight complicating the group- ings, it seemed as though more than a half-hearted study might be beneficial. This may be a good time for you to
plop into a comfy chair and, if you de- sire, grab a cool one. Since this is about a two or three cool one article, I suggest you make plans accordingly. Also, this is a good place to warn you that I might, on one or more occasion, deviate from the topic being discussed to delve into a topic of interest or importance to us as shooters, handloaders, etc. The first step in any project is
determining how to proceed. Addition- ally, it is necessary to have the mind set to determine something, not to prove something. I don’t, shall we say, have a dog in the fight and just want to know the correct answers to the questions. After some thought, I decided to select 11 cases having near minimum rim thickness, 11 cases having “middle of the road” rim thickness, and 11 cases having near maximum rim thickness. Said cases would be grouped into Group 1, Group 2, and Group 3, respectively, and then I would carefully load the 33 selected cases with the accuracy load for the 0.6 MOA rifle and wait for a light wind day. When such a day occurred, I would go to the rifle range on our deer lease and shoot six five-shot groups as follows:
Step 1. 3 shots, 1 from each Group
for fouling. Step 2. 6 5-shot groups, all at 100
yards, as follows: A. target a, one shot from Group 1
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