Bullet Structure. Pet Loads Win. Slugr

Transcription

1 Bullet Structure Pet Loads Win. Slugr

2 The Handloader Mugurine Dave Wolfe Publisher Neal Knox Editor Roger T. Wolfe. Ph.D. Associate Editor Edward M. Yard Technical Editor Norm Lammers Technical Adviser Homer Powley Ballistics Adviser John T. Amber Editorial Adviser James D. Carmichel Cast Bullets Parker 0. Ackley Wildcats & Gunsmithing Wallace Labisky Shotshells John Wootters Gun Tests Harvey A. Donaldson Historical Adviser Ken Waters "Pet Loads" Maj. George C. Nonte Jr. General Assignment Don Zutz General Assignmen 1 Bob Hagel Hunting Adviser A. Robert Matt On Gun Laws John Buhmiller African Cartridges Barbara Killough Advertising Director June Skillestad Circulation Manager Leah Close Asst. Circulation Mgr Rod Guthrie Staff Artist Judy MacDonald Editorial Assistant July-August, 1969 Vol. 4-No. 4 Rt. 4-Box Peoria, Ill Features: Specialty Loads for the.357 Magnum... It's What You Hit Them With... John Wootters Les Bowman Cast Loads for the Carmichel Tempering - Exploded Myth... R. M. Hamson 20 Gauge Slug Loads... Warllace Labisky Bench Rest Loading... Jim Gilmore Pet Loads Winchester Ken Waters.22 Jet Mag.... Willis S. Hobart Pr-ure Factor - Part W... ~oyd Brownell, PkD. Norma Load Data Corrections... Staff Departments:.. Answers, Please. 5 Tip to Tip. 12 Editmarl... 6 Reader By-Lines Lock, Stock Barrel... 8 Propellant Profiles Harvey Donald The HANDLOADER, Copyright is published bi-monthly by the Dave Wolfe Publishing Company, Rt. &Box M82 (1406 Hendryx Place), Peoria, Illinois (Also publisher of Rifle Magazine). Telephone (309) Second Class Portage paid at Peoria, Illinois, and additional mailing offices. Single copy price of current issue-75c. Subscription price: six issues $4.00: 12 issues $7.00; 18 issues $9.50. (Outside U.S. possessions and Canada $5.00, $9.00 and $12.50). Recommended foreign single copy price, $I.OO. Advertising rates furnished on request. Publisher of The HANDLOADER is not responsible for mishaps of any nature which might occur from use of published loading data, or from recommendations by any member of The Staff. No part of this publication may be reproduced without written permission from the editor. Manuscripts from free-lance writers must be accompanied by stamped selfaddressed envelope and the publisher cannot accept responsibility for lost or mutilated manuscripts. Change of address: Please give one month's notice. Send both old and new address, plus mailing label if possible, to Circulation Dept., The HANDLOADER Magazine, Rt. 4-Box 3482 (1406 Hendryx Place), Peoria, Illinois Official Publication of Santa Barbara Reloading Association Your July-August Cover Ponsness-Warren, Inc. is a newcomer in the reloading industry, but in just a few short years the Ponsness shotshell presses have been well received by users and they have been given good reports In the gun magazines. We have been using a Size-0-Matic progressive tool for several years -- with excellent results. On our cover is the Du-0-Matic, a single-stage, two-gauge machine introduced last year. Test report on this press is forthcoming soon. Staff photo by Willard Willis. 4 Handloader - July-August. 1969

3 By Wallace Labisky AST DECEMBER THIS WRITER L spent the better part of a week skulking through tall, dense marsh habitat in quest of a set of really good whitetail antlers. My gun on this junket was a slick-handling Browning Buck Special in the Light 20 model, stoked with superbly accurate rifled-slug handloads. Undergunned? Not in my book. But a number of other hunters I chanced to meet afield didn t share this opinion. Their criticism came as no surprise, because as a buck-buster in shotgun-only areas the.615-inch tube has never been wildly popular. The deer-stalker types, once they take a quick squint at factory ballistic charts, tend to give the 20 the old thumbs-down treatment. Granted, the 518-ounce rifled slug seemingly rates as a lukewarm contender when its energy is compared with that of the 1-ounce 12-gauge projectile. The 20 is roughly 26 percent less authoritative at 25 yards; about 40 percent behind the 12-bore at 100 yards. But at the usual brush-shooting 26 distances, which over the long run probably average out somewhere on the near side of 50 yards, it is our opinion that the 20-gauge slug is not as sorely lacking as many would have us believe. Look at it in this light. If the.44 Magnum handgun cartridge with a 240-grain bullet can be classed as a deer load (and many swear by it), then the 273-grain 20-gauge slug with its much larger frontal area and slightly higher muzzle velocity certainly merits a lot more recognition that it has been given. There are, of course, other facets to consider. Those same sterling assets that make the 20-bore a top-drawer ckoice for many phases of upland work are also advantageous in the deer haunts. Weight is one. The 20 won t wear you down over the long haul; its ammo is less hefty, too. Recoil and muzzle blast are appreciably milder than for the 12, both of these factors being conducive to more accurate, flinch-free shooting. An attribute of no less importance is the 20 s pronounced handiness in The Browning Buck Special in the Light 20 model was chosen for test shooting. The 23%-inch barrel with fully adjustable sights gave top-drawer accuracy. Acces sories include quick detachable swivels and carrying strap. g e ne r a1. With the fast- b o u n ding whitetail on the agenda, and depending on conditions of cover and terrain, getting on the target a shade faster than with a heavier, more ponderous gun might just spell the difference between venison on the pole or none at all. You may disagree that the slug-loaded 20 merits a place on the whitetail scene. But on the chance that you do concur, our next order of business will center around the crafting of accurate handloads. I may be crawling out on a shaky limb when I say this, but I have a strong feeling that the 20 is inherently capable of tighter grouping with rifled slugs than are the larger bores. To my knowledge, Federal, Remington and Winchester have never offered rifled slugs as a handloading component. The Vitt slug, that powerhouse projectile with attached Handloader - July-August. 1969

4 With 20-Gauge Slugs wadding, is offered in 12-gauge only. And if you want the somewhat similar Brenneke you ll have to steal them from factory loads. Most of the few commercial sources that once existed for ready-cast rifled slugs seem to have dried up. Currently, the only one that I am aware of is Meyer Bros. (Wabasha, Minn ), and this outfit can fil your needs in all three gauge sizes-12, 16 and 20. For those handloaders who would prefer to work from scratch, Lyman offers slug moulds in all gauge sizes - even in.410 bore. Only pure, soft lead should be used. Slugs cast in the Lyman mould are smooth-sided and can be used just that way. At one time Lyman offered rifling dies, but these may now be a discontinued item. When wringing out my Buck Special 20-gauge from bench rest, I used the Meyer Bros. (M-B) rifled slug. This is a Foster-type design, such as used in all U.S. factory loads, but with some interesting modifications. In addition to having a hollow-point, the M-B slug has a trio of thin-line cuts that angle upward and outward from the floor of the nose cavity. These grooves (about.006-inch wide) divide the nose of the slug into three equal parts. Their purpose is to induce slug break-up immediately following penetration, thereby imparting more severe boiler-room damage for cleaner kills on deer-size game. According to the manufacturer, contact with brush will not trigger slug break-up. Whether the M-B hollow-point missile breaks into three pieces subsequent to entry, I cannot say from personal experience. In this article I had hoped to be able to verify the manufacturer s claim, but much to my disappointment that sought-after buck did not show himself while I was carrying the Buck Special 20. I can, however, attest to the fact that the M-B 20-gauge slug is capable of outstanding accuracy, as we shall see a bit later on. Despite being hollow pointed, the 20-gauge slug is of full weight. Ten slugs that were weighed individually on my Handloader - 1uly-August Lyman-Ohaus M-5 scale averaged grains, with an extreme spread of 5.5 grains. When loading for accuracy tests, this weight variation was ignored and the slugs were simply picked at random from the box. Length runs.700-inch, while the outside diameter (measured across the lands of the rifled section) tapers from.550 up forward to.600 at the base. Even highly polished bores are prone to accumulate some lead fouling with rifled slugs and for that reason the M-B offering is heavily coated with graphite. This approach alleviates lead build-up, but it does not eliminate it. When running accuracy tests, I make it a practice to scrub the bore clean following each five-shot string. Top-flight slug loads start with good sound hulls. In the interest of uniform ballistics and, in turn, tight grouping on target, hull selection should be approached on the basis of minimal variation in shell-mouth strength. And, of course, it is also of importance that the loaded rounds be uniformly crimped to the same overall length. With this in mind, I contend that by far the best bet for hunting loads, as well as when test shooting to determine the most accurate load for a given barrel, is to expend a few extra pennies for new cases. In 2 3/4-inch 20-gauge persuasion, the available paper-tube hulls are Federal Monark and Winchester Ranger. The only usable plastic hull in this bore size is the Remington SP shell in the field-load version - not the target load shell, as the skived-mouth design does not pan out very well with the required roll crimp. The wall thickness at the mouth of these is not adequate to properly secure and center the rifled slug in the shell. My vote goes to the paper-tube shell simply because it is easier to roll crimp In general, group size can be expected to increase appreciably when there is no hard wadding directly under the rifle slug. This 4% inch group was shot with 29 grains of AL-5 behind a PGS and Mono-Wad (load No. 4 in the table). A good example of deluxe style deer poison is this 50 yard fiveshot group in which four 20 gauge M-B slugs chopped out the X ring on a loqyard smallbore target. The flier opened the group to 1 5/8 inches center to center. The powder charge was 29 grains of AL-5 (load No. 5 in the table). Another example of gilt-edged accuracy of the 20 gauge Browning Buck special teamed with M-B hollow point rifle slugs is this five shot group which measures 1 5/8 inches. The slugs were driven by 26 grains of Hodgdon s HS-5 (load No. 8 in the table). 27

5 on my Lyman Easy shotshell tool (requires fewer press strokes). Also, I favor the Federal offering over the Winchester, because the former with its low basewad provides plenty of capacity for the wad columns that I feel are conducive to top-hole accuracy. Meyer Bros. rifle slugs are heavily graphited to alleviate leading in the bore. The hollow-pointed nose section is designed to cause the slug to separate into three pieces immediately following penetration. It is not likely that you will uncover a worth-while supply of previously fired 3-inch 20-gauge hulls that were originally roll crimped. But if Dame Fortune smiles, don't hesitate - smile right back. When trimmed back to 2 3/4, these empties are almost the equal of new hulls. Next in terms of suitability among previously fired Sinchers are those which were originally fold crimped. Trimmed to length, they can be reserved for slug loads intended for practice shooting. The poorest of all choices is the shell that was originally fold crimped. Trimming back such hulls not only means that the wad column must be shortened, but the sub-length shell introduces the possibility of slug wobble as the projectile makes the jump from shell mouth to bore proper. This wobble doesn't do a thing for accuracy. For pushing the 518-ounce 20-gauge rifled slug at top muzzle velocities in the 1,500 to 1,600 fps range, those propellants such as AL-120 and Unique, which do such a fine job behind the heavier 1Zgauge slug, are not suitable. Being fast burning, these fuels will cook up devastating chamber pressure in the.615 bore. Required for the 20 are shotshell powders in the medium-burning class. AL-5, HS-5 and Herco were used in my tests and all three produced excellent results. Velocity and chamber pressure proved compatible, and there was no evidence of incomplete combustion in the Buck Special's 23%-inch barrel. Others which should prove equally suitable for slug loads, but which I have not tried in that capacity, are Du Pont SR-7625 and Norma COMMENTS: Wad seating pressure was 70 pounds for AL-5; 40 pounds for HS-5; 100 pounds for Herco. New, factory-primed 2-3/4" Federal paper-tube field-type shells used for all loads listed. Wad column lengths listed permit roll crimping to an overall shell length of 2-3/8", plus or minus 1/32". All test firing done from bench rest, and group measurements were taken center to center of widest hits. Bore of gun was tharoughly cleaned following each five-shot string, 28 The wad column is really the heart of any slug load and, to my thinking, it is by far the ranking factor controlling accuracy. The column that is top-notch for a shot load usually proves to be a ten-carat flop with slugs, as a good many handloaders can attest. Basically, wad column requirements for both types of loads are identical. The column must provide obturation; it Handlaodsl - July-Aupurt, 1968

6 must provide cushioning to avoid a premature peak in chamber pressure; and it serves to regulate crimp space. In the slug load two additional functions are required. It must provide an evenly distributed transmission of energy to the base of the slug; and, even more importantly, it must resist being driven into the base cavity of the slug, because when this happens accuracy goes to the dogs. So the too-soft column is to be avoided. These two extra requirements can be met, quite effectively, by using hard card wads directly under the slug. One.2OO nitro card should be regarded as the bare minimum for this platform, and two are better. When two card wads of different thicknesses are employed, such as a.135 and a.200, always place the thicker one next to the slug. It is interesting to note that in Federal and C-I-L factory slug loads the approach to this problem involves the use of cone-shaped plastic plugs which are inserted into the slug cavity. With the.700-inch-long 20-gauge M-B slug, build the wad column so that one inch of space remains between the topmost wad and the shell mouth. This leaves an adequate 5116-inch above the slug nose for applying the roll crimp and results in a finished round measuring inch overall. An overshot or B card should never be placed over the slug. It serves no useful purpose and, in fact, it is a dangerous practice. The slug could easily override the B card and cause a bulged barrel. Care should be taken during the roll-crimp operation to see that the slug does not become locked in a tilted position. With its hollow-point nose, the M-B slug is an easy one to square up just prior to applying the final stage of the turnover. However, this small problem is not likely to arise unless the loading tool s wad ram, which in virtually all instances is a good bit smaller in diameter than the shell, is badly off-centered when inserting and pressuring the column. To avoid this trouble, obtain a short piece of wooden dowel stock that gives a slip-fit in the shell. Square the dowel off at both ends and use it between the wadding and the tool s ram when seating the column. This way you ll be assured of a level platform for the slug. Handloader - July-August All test loads were assembled in new, unfired Federal paper-tube hulls. With HodgdonS HS-5 powder, the wad column giving the best accuracy consisted of a PGS, le-inch Mono-Wad and two.200 card wads directly under the 20 gauge M-B slug. Shells were roll crimped on the Lyman Easy tool to an overall length of 2 3/8 inches. For the 20 gauge, a dowel of 9116-inch diameter does the trick. With powders that require heavy wad-seating pressure, such as Herco (100 pounds), or when the column consists of four or more wads, I feel it is best to apply the pressure in two stages. Looking at Load No. 13, for example, 100 pounds was used on the PGS and the Mono-Wad, 60 pounds on the two card wads. And for Load No. 2, 70 pounds was applied to the PGS and.135 nitro, while 50 pounds was put on the 3/8-inch filler and the two.200 card wads. Two-stage pressuring gives more BALLISTICS GAUGE RIFLED SLUG HANDLOADS SHELL: Federal 2-3/4 Paper-tube (new) PRIMER: Federal 209 PROJECTILE: Meyer Bros. 5/8-0z. Hollow-Point CRIMP: Roll (Overall loaded length 2-3/8 ) (Continued on Page 63) Load Powder Wad Velocity** Chamber Extreme Charge Column Pressure Variation fps psi 2 AL-5 PGS NC + 3/8 FB 1,576fps 11,OOOpsi grs NC NC 5 AL-5 PGS + 9/16 M-W ,614fps 11,775psi 20 1, grs. 8 HS-5 PGS + 1/2 M-W NC 1,487 fps 9,975 psi 47 1, grs NC 13 Herco PGS + 1/2 M-W NC 1,491 fps 9,975 psi 49 1, grs NC *Velocity and chamber pressure listed represents on overage for four shots. Tests conducted by Alcan Boll istic Research Department. **instrumento1 velocity at 12 feet from the muzzle. COMMENTS: An average chamber pressure of nearly 12,000 psi, as produced by Lood No. 5 (one individual round in this test peaked at 12,500 psi), is approaching the very thin line thot separates high pressure from dangerous pressure. All 29/AL-5 loads employing the Ljutic Mono-Wadshould be REDUCED about 1.5 grains, ond os such should be considered MAX. Also, to provide a good safety margin, all 29/AL-5 loads employing Feltan-Bluestreok or similar filler wadding (Lood No. 2), should be REDUCED by 0.5 to 1.O groin SO OS to bring the average pressure down to around 10,000 to 10,500 psi. 29

7 U'IDE W Z c s, pis Hercules Unique is o versatile and useful powders available to the handloader. This propellant is I 70 years old and still going str,.., troduction of dozens of wders with overlapping Ilnzque BY John Wootters lulll&;s, u1 w HERCULES" L aiwayb gurren :eptional accuracy with it as long as I confined myself to gas-checked or body-jacketed bullets. Plain-base cast slugs sometimes give barrel-leading even at medium speeds with Unique, apparently due to the high me cfl I E lnnr double-base powder (about 40 perceni nitroglycerine) with 90 percent the relative quickness of Hercules Bdseye powder and about 96 percent thr relative force. On a relative quicknesc scale of all reloaders' powders, Unique appears on the faster-burning side of Du Pont SR Physically, Unique is in the form of gray, round flakes, about.065" in diameter and.006" in thickness. As thrown from a reloader's powder measure, it has a bulk density oi about.52 using water as a reference of This indicates that Unique is fairly fluffy, yet it measures through shotshell loaders' charge bars and bushings and through powder measures with adequate uniformity for most purposes. Unique is noted for the ease with which it is ignited and burned, although in many loads it tends to leave a residue in the barrel after fxing. This powder is non-hygroscopic, which means it does not readily absorb moisture from the atmosphere; indeed, Unique is almost waterproof. Thus, Unique has extremely long storage life in the hands of a reloader, who may not be as careful as he should to see that powder cans are tightly sealed, or w'-- mav liv -1 an area of high humiditj num") pruners h IJniniie in a1 22 Jet. For many y. 570 While ULL,..e may -2 used fo, ".." 11 range of bullet weights at maximum 00-gr. cast. 1,700 velocity in the.357 Magnum, it truly 1886 Winchester only) I ;hines in this cartridge in midrange gr. cast HP or 3r "'7 1, i30 '?20!OO 120 I50!OO 1,750 I90 1,425 2,050 2,040 'UU

8 temperatures. This comment applies with equal force to similar cast bullets in rifle cases. As a rifle powder, Unique is strictly for light gallery loads. Even in the smallest cartridges Hornet,.218 Bee, etc. -- it is too fast-burning for top velocities with jacketed bullets. There is no rifle cartridge extant, however, in which Unique is not one of the powders-of-choice for midrange cast-bullet loads, and in such loadings it almost always delivers excellent accuracy. This is probably due to its ease of ignition and uniform burning characteristics, regardless of its position in the case relative to the primer. This is a matter of importance wherever loading density is extremely low and no fdler is used, as is the case in most cast-bullet loadings. Unique may not prove to give the very best accuracy in such loads in any individual rifle, but it is always a safe bet for starters. Some of my own pet loads with Unique are as follows: Repeater (Model 92 Winchester with bushed firing pin and a little headspace)... 5 grains / 8 5 -grain Lyman U gas-check for just under 1,700 fps.,257 Roberts grains/85-grain Lyman U gas-check for about 2,000 fps (with one grain of Dacron filler)..308 WCF.,. 10 grains/l62-grain Lyman U gas-check for 1,335 fps (with 1% grains Dacron filler) and a beautiful squirrel and small game load. 7x57mm Mauser grains/ 136-grain Lyman U gas-check for 1,760 fps ,, grains/lll-grain Lyman gas-check for about 2,000 fps and a real turkey load Magnum (revolver) grains/l25-grain Super Vel JSP for 1,450 fps. 9mm Luger... 5 grainslll9-grain Lyman for 1,150 fps. 9mm Luger grains/90-grain Super Vel JHP for 1,320 fps. Hercules offers Unique in 13-ounce canisters, and 3-pound, 8-pound, and 15-poun d kegs. The larger-quantity containers are not a bad idea, since most reloaders -- especially those loading a variety of pistol cartridges or shotshell reloaders - find that Unique is a hard powder to keep in stock. 52