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Rifle

The Magazine for Shooters

"Only accurate rifles are interesting"

- Col. Townsend Whelen

Volume 8, Number 4 July-AuguSt 1976

IN THIS ISSUE

New Study Shows Gun Law Failures. Pyrodex Replica Black Powder.

.................Neal Knox

DEPARTMENTS

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..................... John Bivins 6mm Swift.. .....................................Jim Hanson Bedding the Browning 78.. ..................... .Frank de Haas Testing the Smithons. ............................. Clay Harvey Mauser G.33/40 Development. .................... Les Womack

.280 Ross.

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............. 10 Sighting Shots.. ...........12 Aiming For Answers.. ..... 14 NBRSANews ............ 34a Classic Rifles.. ............35 Bench Report. ............ 64

Dear Editor.. Trophy Pointers..

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......... 66

Lloyd de Vore 32 .Don Lewis Bob Milek

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............................ Charter Arms Police Bulldog.. .......................

Today's Shotgun Slug..

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This Month's Cover

Adopted in August 1969 as Official Publication For National Bench Rest Shooters Association

It isn't t o o soon t o begin preparing for the upcoming big game seasons, working u p loads, accurizing rifles, etc. The Savaqe M-111 with detachable box magazine and carrying i i n g is leaning against an Arizona elk taken by Rick Jamison a few years ago. The .30-06 with 4X Weaver scope in Conetrol mounts makes a fine elk hunting combination. Photo by Rick Jamison.

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RFLE Magazine, copyright 1976, is published bi-monthly by Wolfe Publishing Co., Inc., (Dave Wolfe, President), P.O. Box 3030, Prescott, Arizona 86301. Telephone (602)445-7810. Second Class Postage paid at Prescott, Arizona, and additional mailing offices. Single copy price of current issues $1.25. Subscription Drice: six issues $6.50; 12 issues $11.50; 18 issues $15.50. (Outside U.S. possessions and Canada - $7.50, $13.50 and $18.50). Recommended foreign single copy price $1.50. Advertising rates furnished on request. All rights reserved.

T h e Staff

Neal Knox, Editor and Publisher Ralph Tanner, Jr.9 Sales Director Rick Jamison, Associate Editor Dave LeGate, Art Director Barbara Pickering, Production Supervisor Bobbie Roach, Editorial Assistant Richard Aldis, Staff Photographer Joyce Bueter, Circulation Manager Terry Bueter, Circulation Jana Kosco, Executive Secretary Wanda Hall, Accounting R. T. Wolfe, Ph. D., Consultant

Technical Editors

Publisher of R F L E is not responsible for mishaps

of any nature which might occur from use of

published 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 self-addressed 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., RIFLE Magazine, P.O. Box 3030, Prescott, Arizona 86301.

John Bivins Bob Hagel Clay Harvey AI Miller Maj. George C. Nonte, Jr. Homer Powley Jon Sundra Ken Waters Edward M. Yard Don Zutz

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RIFLE Magazine

In HandloadingAccuracy is the name of the game Warren Page tells how to build, tune select loads and shoot "One-Hole" rifles --Whether designed for competition or hunting.

Answers

Carbon Tet Danger

Many thanks to George Nonte for his new book Pistolsmithing; it fills a rather large gap in gunsmithing books. However, I have a small criticism - carbon tetrachloride should not be recommended for cleaning because it is a serious health hazard. Instead, trichlorethylene could be used but this too can be dangerous because flames or sparks will break down the fumes to phosgene which further breaks down to hydrogen chloride. Since most hobbyists have a basement workshop, a large vent fan is almost a necessity for any solvent. Where can 1 get European Style ''Claw" scope mounts and bases. Harry Stewart Nevada City, Calif.

The claw-type scope mount bases popular in central Europe have never been available as a production item. Though designs were fairly standardized, they were generally made within that firmat by the individual gun makers and were not interchangeable between makes. In fact, more oj?en than not, two sets by the same maker would not interchange.

THE ACCURATE RIFLE

BY W A R R E N PAGE Published by Winchester Press

Ever since the development of gunpowder, riflemen have yearned for the ultimate in rifle accuracy-the ability to put shot after shot through the same identical hole. This brandnew book examines this search for greater accuracy from every aspect and details for target shooters and hunters alike the best procedures for making their rifles superaccurate. Warren Page, winner of nine national bench rest titles, provides the shooter and hunter with detailed practical information on every subject affecting accuracy and analyzes the techniques employed by competitive shooters in creating the equipment and methods that have produced modern rifles consistently capable of holding their shots within '/4 inch at a hundred yards. His topics include: Best methods of shooting from a bench rest; the most accurate sights and scopes and their use; the problems created by wind and mirage and how to deal with them; the role of recoil in rifle accuracy; the secrets of bedding a rifle, relating the metal t o the wood for peak performance; how t o make or select barrels and stocks for the best accuracy; how to select or develop the superaccurate loads that will give the best results in a given rifle. This is the most up-to-date, authoritative discussion of rifle accuracy anywhere in print. Not only a must for the serious competitive shooter, but highly useful for the practical hunter seeking to increase the size of his bag.

H A N D L O A D E R PRESS Box 3030 Prescott, Arizona 86301

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However, inasmuch as you desire a Robert Cella complete set of both rings and bases, I Barryville, New York suggest you write Paul Yaeger, 211 Your criticism regarding the use of Leedom Street, Jenkintown, Pa. 19046. carbon tetrachloride is well taken. He may be able to help you. However, in the quantities that a gun buff George Nonte might use it, and with the extremely low frequency of exposure that would 2 5 7 Roberts Twist normally result, I do not consider it a I have a Sako W9 (Forester action) and serious health hazard. Nevertheless, I normally caution against its use without wish to build a light, accurate deer rifle adequate ventilation and against inhala- for my wife and daughter. tion-of the vapors. I believe I did so in I would like to use a 22-inch the work to which you refer. lightweight barrel in .257 Roberts. As I George Nonte pfan to i s e 87 to 100-grain bullets, what

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Enclosed is $ . for -copies I of THE ACCURATE RIFLE @ $8.95. If not completely satisfied, I may return the I books within 10 days for a full refund.

Name ................................. Address ............................... City ................................... State ..................... Zip ........ (Arizona residents add 3 6 e Sales tax)

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Fully Adiustable With Side Safety

Fits all Model 98 Mauser Actions Fits 93/95 Mauser Actions with minor fittings Installs on action in seconds May require minor stock inletting $27 00 Value Special purchase Yours for only -

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SHERWOOD ISTRlBUTORS IN(

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18714 Parthenia Street, Box R-7 Northridge, Calif. 91324 (213) 349-7600

RIFLE Magazine

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twist would you recommend and will I have any problems with magazine length, ih feeding, or throat problems if I stay w t a standard throating? I don't plan any long throating or the use of heavier bullets as this gun's use will be limited to Texas whitetails and desert mule deer in the Big Bend country. John R. Pack Waco, Tex.

Your Sako Forester action will do very well f o r a light ei 'r f o r the .257 Roberts cartridge. The magazine will handle the cartridge with bullets seated for normal thmating in all weights. Zt will not be long enough to use an overall cartridge length o much over factory dimension, f but i f you should ever wish to use the longer bullets like the 120-grain pointed, you can do so by seating them with bases farther into the case. There will be no problems as long as you stick to factory overall cartricige length and do not use a bullet with such a long bearing [email protected] that they jam into the lands. You will, oj course, have to avoid seating that will cause the bullet to be forced into the lands with any bullet weight. This will not normally happen with this magazine length and standard thmating with most bullets. I'd use the standard 1-10 twist. Zfind it does very well with all bullet weights in this cahridge. Bob Hagel

Break Action Rifle

I would like to know what single shot shotgun now on the market would be considered the strongest. I am t h i i i n g about using a single shot shotgun action to make a single shot rifle with interchangeable barrels for different calibers. I would like to know what shotgun would be strongest and how powerful a cartridge could be used in i t

The reason I would l i e to do this is to chamber for some of the older cartridges, say .25-u)to .405 Winchester, or more powerful if possible. It seems this would be a cheaper way to have a shooting rifle for old calibers than trying to buy an original. D e this sound logical? os James Stuart Tekousha, Mich.

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How do you measure the worth of your ammunition? By accuracy and effective performance.. . or by price? Norma ammunition costs more because we believe in only making the best. Each Norma cartridge is precision-manufactured and quality-inspected to the strictest standards in the industry. Our brass is renowned as "Second only to gold" for its quality, consistency, and color. Every cartridge is a blend of superior brass case, bullet, powder, and primer. . . meticulously matched to give you constant accuracy and optimum performance.. . to make every shot count. Exceptional accuracy has made Norma ammunition the choice of leading arms manufacturers for factory testing. It IS available in many popular domestic and hard-to-get foreign calibers. The price you pay for Norma pays off in superior accuracy and performance.

Z assume that you are inquinirg about the typical break-open single-barrel shotgun actions that are generally available in this country. By that, Z mean you are not refirring to the double and triple-bolted, cross-bolted, and otherwise reinfbrced actions sometimes found on the very costly British and European guns. Based on that assumption, Z would say that the H % R Topper action is regularly manufactured in .30-30 and .45-70, as well as some other smaller calibers. I have yet to hear o any [email protected] with this f yet action when so chambered

`norma 1

norma-precision

Lansing, New York 14882

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July-August 1976

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apparently none of the other makers feel [which is of course in itsfavor]. However, like adapting their break-open actions to the Ruger No. 1 [particularly with its Alex Henry fore-end] conveys a strong high-power njle calibers. impression of the great old English For your purposes, I would suggest that single-shots of Aji-ica and India fame. Z you look into the H&R Topper, perhaps like them both! obtaining one with one or two spare In one respect, the Ruger No. 1 has an barrels and then relining those barrels to advantage in that it is offered the rijle calibers of your choice. alternatively as a barreled-action f o r those George Nonte shooters who may wish to design their own stock. Browning should do likewise and also supply actions only. Browning As you have noted, the Navy Arms I have been a reader of your articles on Rolling Block does possess surprising the .45-70 cartridge and some of the rifles chambered for that old shoulder buster. I strength, and I have mentioned this own a Navy Arms Rolling Block and have several times, especially since experimentdone some of my own experimenting and ing with one chambered for the big .458 have been amazed at the N.A. action RCBS cartridge. I likewise agree with you on the use of 300 and 400 to 405-grain strength. bullets in the .45-70. Personally, I can't But my main reason to write is my see 500-grain bullets in that short case excitement over a newly acquired cartridge [and I have used plenty of Browning 78 in their new .45-70 them]. They take up too much room in chambering. If you haven't seen this rifle the case, are too slow, create too much you have a real treat in store for yourself. recoil, and have too curved a trajectory. And if you have had a chance to see and But that's just one man's opinion. work with one I would appreciate your Ken Waters impressions.

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them both ways.

The Remington bullets you bu for hand loads are the same bu lets we put into Remington factory loads. That means they're made to the same exacting standards. What's more, it means they're tested for compatibility with our other quality components. Remington's jacketed and lead bullets come in all standard rifle and pistol calibers and just about every popular style. lncludin 31 different "CoreLokt" bullets or big-game hunting and 8 different "Power-Lokt" bullets for super varmint and target accuracy. When you load Remington bullets, you get payloads that pay off with hard-to-match performance. Write for your free Remington Ammunition Components Catalog to: Remington Arms Company, Inc., De t. 488, Bridgeport, Connecticut

I like to work up various loads by bullet weights but I generally end up with the 300 or 400-grain bullets. I'm usually rewarded, accuracy-wise, with a medium handload and would like to hear any of your favored comments as to the specific bullet used in the 78 rifle. Because of the traditional design of this Browning 78, I'm wondering if it will not become more popular and more sought after than the Ruger No. 1 in the same caliber. Strength of these two actions might even be comparable. Terry W. Ford Seguin, Tex.

280 Silhouette Rifle

I am in the process of working up loads for a .280 Remington silhouette rifle and am quite concerned about the ballistic coefficient of the various 7mm bullets as trajectory must be computed to 500 meters. Why do bullets with similar sectional densities and apparently similarly streamlined shapes have greatly different published ballistic coefficients (and trajectories)? An excellent? example of this is the 140 Sierra, 139 Hornady and 145 Speer which have B.C.'s of .490, .390 and .425 respectively as listed in their manuals. Dr. James L. Nitsos Kent, Wash.

Y

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&*.

both

Great suns deserve great ammunition. We make

"Core-Lokt" and "Power-Lokt" are trademarks registered in the U.S. Patent and Trademark Office.

"Remington",

I don't have a Browning Model 78 in .45-70 caliber, but do have one in .25-06, so am familiar with the quality All bullets of the same weight and workmanship and material of this fine single-shot rifle, as well as its smooth caliber have the same sectional density, but there is a great deal of difterence in finctioning and ingenious ejecting. the ballistic coeflcient of those same Needless to say, Z like this rifle very bullets. Even though they look very much, and while not attempting to claim similar in shape to the untrained eye, they credit for anything, I'll mention in vary a good deal. passing that when the Model 78 appeared Your examples bring up this same and my early issue test gun arrived, Z recommended to Browning that it be point. The reason the 140-grain Sierra has produced in .45-70 caliberfor the many a higher ballistic coeflcient than the traditionalists and lovers of big bores. No others is because it actually has a more While the doubt, countless other writers did the streamlined point shape. Hornady 139 is pointed, it is of a difterent same. shape. The 145-grain Speer is somewhat Both the Browning 78 and the Ruger less pointed, but is heavier so has a fairly No. 1 are extremely strong njles, capable high ballistic coeflcient. The latest Speer of handling any pressures that the .45-70 B.C. is listed at .459. case can produce with suitable powders Actually, not everyone agrees on the and loads. Naturally, this does not include the fast-burning pistol powders. B.C. of any given bullet who computes it without actual testing for velocity over a As f o r esthetics, it's true that the given range. Browning bears a very strong resem blance Bob Hagel to the beloved old Winchester High Wall

RIFLE Magazine

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Ideal cure for a shot-out

The more time I spent afield with the Swift, the greater affection and respect I gained for the cartridge. Had not a Kentucky hunting regulation prohibited the use of rifles smaller than .240 caliber on deer, my Swift would have had an even more extended season. But I'll confess that the heavy use to which I was putting it was making me wonder about how long that barrel would last, considering one of those other warnings about the Swik that its barrel has an exceedingly short life. Because of that hunting regulation, I was in the woods during deer season with a variety of M-70 .243's,a cartridge that others strongly favor for Swift-type varmint hunting, as some classify such matters. But I was never able to develop the affection for that short-necked and fat-bodied cartridge that I held for the graceful Swift; despite its good points, the advantages of the .243 Winchester are pretty much wasted on a Swift freak. In fact, my feelings for the 243 never came to much more than mere tolerance. The only thing it had that the Swift didn't was a larger diameter bullet. Such was my mental condition during a rainy afternoon's d i n g session when I came across mention of a .220 Swift cartridge shooting 243 bullets. Claims were made for a 60-grain bullet clocking 4,113 fps MV; a 75-grain-slug doing 3,790; 3,640 for a 90-grain bullet velocities equal to or exceeding those of the 243 Winchester, with two to four grains less powder. These are impressive f figures, even with a liberal dose o Morton's best-knqn product. Maybe there was something better than the .220 Swift.

1

HE .220 SWIFT is supposed to be a s p e c i a l i i cartridge, an adjunct to the varmint rifle battery for use only on those days when the ranges are long and the winds are high, but I was using my Model 70 Swift for almost all my varmint shooting. So enamored was I with the camdge, and being blissfully ignorant of the prophesies of doom befalling those who loaded less than full-throttle loads, I tinkered about a bit and discovered an accurate reduced load that did in even die-hard fox squirrels with a minimum of meat loss and virtually no crippling. The season of tbe Swift was thus extended from mid-May groundhogs through the last squirrel of October.

T

For some mysterious reason, the cartridge development was never fully pursued, nor do any of my major references - Sharpe's Complete Guide To Handloading, Barnes' Cartridges Of The World. Ackley`s Handbook For Shooters And Reloaders No. 1 and No. 2, nor aliy of the early loading manuals Belding & Mull Handbook, Speer Wildcat Manual, etc., contain any mention of such a cartridge. Only a half-page in C.S. Landis' Woodchucks And Woodchuck Rapes gives any hint that such a round ever existed.

On page 306-307 of Landis' book, in

From left are the UMC 6mm Lee Navy cartridge showing headstamp, a WRA 6mm Lee Navy cartridge, the .220 Swift based on the Lee round, and the 6mm Swift [formerly the .236-220 Gipson] a .220 Swift case opened at the neck to accept .243 diameter bullets.

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RIFLE Magazine

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--T4.J

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By JIM HANSON

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lrrel

The cutaway caws, facing page, show tho tntomal dlffennces between the .243 Wlnchester, top, and the formed but unUmd'6mm Swlft case. The .243 Wlnchasbr, when fllled to the baa0 of the neck, has a cepaclty bf 51.1 g n l n s water. Tho 6mm Swift holds 45.1 gmlns u n f h d , and 45.9 grains flm-formed and full-length slzed. Hanron's 6mm Swift, above 8ceount.d for two antelopo wlth the 95graln Nosier ahead of 47.01H-450. Volocltlrrr of the 105-graln Spew bullet In the wlldcrt equal those of the .243 Wlnchrster, making It an excellent choice for deer as well.

the chapter on Vernor Gipson products, dispatcnea to Lake a ".236-220 Gipson" is described as reboring and barrel-swapping. simply the .220 Swift case opened out in the neck to accept 243 bullets. The cases, when fired, are given a sharper shoulder angle and a larger diameter at the neckhhoulder juncture, but otherwise retain the typical Swift configuration. According to the Landis account, Gipson built the first, possibly the only, .236-220 Gipson around 1947-48, with a Buhmiller 6-groove, 26-inch Sporter weight barrel, and shipped it to J. Bushnell Smith. Smith worked up some loads, including those previously mentioned, and achieved several 1-inch groups a t 100 yards (MOA rifles apparently being rare exceptions in those days). Gipson and Smith intended to make additional bullets and use the rifle for serious competitive shooting, and Smith made plans to enter it in the u bench-rest matches at D Bois, Pennsylvania in the late summer of 1948. But a heart attack resulted in Smith's untimely death in July, ending work with the cartridge and relegating the development to a forgotten corner.

inside of the case neck with graphite to reduce friction between it and the for the expander ball. No heavy-duty equipment is needed I usually use a C-HNo. 204

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method - simpiy running .220 brasiinto the 6mm Swift sizing die and fireforming to the chamber with a reasonably mild load. Even though the Swift case is one of the strongest made commercially, attempting to develop maximum loads with I was sufficiently intrigued by the brass that hasn't been fire-formed would cartridge to consider some of the likely produce erroneous information and technical problems involved. P.O. Ackley brass loss. responded to my query regarding the The only special considevtion in sizing reboring of the M-70 stainless steel the brass is to chamfer and lube the barrels that .this material seems to rebore as well as the standard material." Not wishing to alter mine, I set about shopping for another M-70 Swif?. The The M-70 .220 Swlft magazlne box, rlght, Is shown for comparison wlth the magazlne one that turned up proved to have an even altsrsd for the 6mm Swift. Removal of the better barrel than the one I already had. front plate In the msgarlne box Is rlmple and That, in turn, set offa search for a "shot allows a greater ovenll Internal Iongth, out" M-70 Swift barrel. Of the four I effectively lncnarlng allowable ovenll certrldge length. Model 7 4 s In .220 accumulated, one had the worst case of Swift cen also bonefit from thlo rlmplo erosion I've seen, and it and the newly modlflcetlon when using 6O-graln or heevler acquired M-70, with a set of dies, was bull.ts.

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Julv-Augua 1976

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a crush-jit, thereby obtaining a tight headspace condition regardless of variations in shoulder angle. This headspacing point may be eliminated when sizing up to a larger caliber: even with jired cases the stress of pushing a larger expander ball into the neck may force the shoulder back, increasing headspace. The $re-formed cases will look normal, but if the excessive headspace condition exists upon jirst Bring, there is likely to be a thin "stretch ring" inside the case, just forward of the web, identical to that o f e n seen inside belted magnum cases. If the bullet bears against- the lands [which becomes the headspace point] the new shoulder will be formed without stretching the but if the has excess headspace, it will be driven forward by the jinhg pin, the shoulder and forward grip the then pressure will drive the head back against the bolt face, causing either a head separation or the concealed incipient separation indicated by the interior groove. - N.K.]

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2.205 f 5 6 . O f m m )

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The 6mm Swift barreled action returned one Friday in August, and 1 spent a frantic period through Saturday morning cobbling together a reasonably accurate load of 41.0/4350 behind a 75-grain Sierra hollow point and sighting in. My hunting buddy and I lucked into a fresh-cut clover-alfalfa field just as the last bales were being loaded onto the wagon. The 6mm Swift accounted for six suddenly exposed groundhogs at ranges I later from 125 to 250 yards.

chronographed the load: 3,181 fps at the muzzle. Not a barn-burning opener, but one that held promise, nonetheless. The next pressing project was to gather maximum load data and find out how true the figures were in Landis' book. I had god to be suspicious of the loads given. Most ardent Swift fans will recognize J. Bushnell Smith as the writer of an article in the August, 1936 American Rijleman claiming the .220 Swift was tricky to load for, couldn't be loaded less than maximum, and unaccountably jumped pressures as much as 15,000 psi. Subsequent unfounded parrotings by such figures by Philip Shave, et al. compounded the problem to the point that even today the .220 Swift suffers a bad reputation from the unwarranted stigma branded on it by Smith`s piece of biased and unjustified writing. By coincidence, Smith was also a professional reloader, self-proclaimed

expert on the .220 Swift, and the only one he considered qualified to load for it. It didn't take much shooting to confirm my suspicions. Smith`s loads, as relayed by Landis, were hot! Some so much so I made no attempt to duplicate them. Those that I did cautiously approach, I found to be as fast as Smith's chronograph measured. The 42.0/4895 load was clocked with three different 75-grain bullets. The Sierra hollow-point clocked 3,737 fps MV, 5-shot average. The Speer turned up 3,732, and the Nosler Zipedo 3,744. Smith listed 3,755 for a 75-grain Barnes bullet with the same powder charge. For my rifle, and for longer case and barrel life, 41.0 grains is maximum. A load in particular I refrained from trying was 46.5 grains 4350 behind a 90-grain Barnes bullet. Smith clocked it at 3,640. The top load with an 85-grain Sierra in my rifle is 43.0/4350 and clocks

In order to form 6mm Swift brass, a chamfered .220 Swift case with its neck coated well inside with graphite is inserted into the sizing die and emerges as the 6mm Swift. Little force is required as is demonstrated by the clamped-down C-H No. 201 aluminum alloy press. The next step is fire-forming. The cutaway 6mm Swift cartridges show seating depth with various bullets. From left are the [ I ] Sierra 60-grain hollow point, [2] Sierra 75-grain hollow point, [3] 85-grain Sierra spitzer, [4] 95-grain Nosler partition, 151 105-grain Speer round nose, and [SI the 105-grain Speer spitzer. These bullets are seated to maximum length allowable to work through the M-70 magazine with the front plate removed.

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RIFLE Magazine

3,325 fps. Loading 46.5 grqins, by the way, fills my W-W cases to nearly overflowing, even with a drop tube. It`s a wonder Smith's cases didn't burst at the seams when the bullet was seated; I would come nearer clucking and laying eggs than firing the load in my rifle.

Working up maximum loads for any rifle is pretty much a cut-'n-try process. Loading manuals give guidelines for commerical calibers and better-known wildcats, and that at least Drovides a starting point, even though the rifle in question may prove to have a three or four-grain tolerance Over the listed maximum. With an unknown wildcat, the operation is strictly a "B'guess 'nEi'god" process. The Speer manual outlines three pressure indicators for determining maximum loads in any rifle/cartridge combination. Flattened primers or sticky extraction by themselves don't tell much, but when a primer shows severe flattening :or cratering, with lighter loads showing normal looking primers, and case extraction begins to make itself felt, maximum has been reached and pressures are becoming severe enough to warrant a reduction in powder. The third indicator is more of a "past maximum"

sign. When a measurable increase (.0005 to .OOl-inch) can be detected in the diameter of the case head after f h g , maximum has been passed, and a reduction in powder is necessary to prolong case life and get back within design working pressures.

expansion. A combination of flattened primers, sticky extraction, and only slight velocity increases when the charge was hiked led me to set working maximum loads rather than absolute maximum. When primers began flattening to the edge of the pocket and a slight resistance could be felt opening the bolt to extract itd The loads l s e as maximum for the the fired case, and most importantly, increasing by no 6mm Swift were the result of the first two velocities leveled off indicators and velocity increases on the more than 50 to 60 $s, for an extra grain chronograph, rather than case head (Continued on Page 55)

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These are some o the groups fired with the f 6mm Swift. Accuracy Isn't benchrest quality, but respectable, nonetheless.

Comparison Data: 243 Winchester and 6mm Swift

6mm Swift: Rifle M-70, 26-Inch barrel; Winchester 120 primers, W-W cases .243 Winchester: Rifle M-70, 24-inch barrel; Winchester 120 primers, W-W cases

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60 SJERRA HOLLOW POINT

8mm Swift Load I Powder 39.91 3031 43 .O I4064 43.01 4095 44.014320 46.5 I4350 30.OIBL-C(2) 41.01 H-335 45.0 IH-300 46.0 IH-414 Veiqcity 3,756 3,931 4013 3,920 3,679 3,600 3,732 3,790 3,764

. .243 Winchester LoadlPowder Velocity

75 SIERRA HOLLOW POINT

8mm Swift Load1Powder 30.0 I3031 40.014064 41 .O I4095 41.014320 44.014350 37.01 BL-C(2) 39.01 H-335 43.01 H-300 45.01H-414 49.011-1-450 Velocity 3,409 3,527 3,655 3,540 3,433 3,322 3,479 3,565 3,610 3,531

.243 winchester LoadlPowder Velocity

30.0 I3031 41.014064 41.014095 43.014320 40.01 4350

3,376 3,514 3,602 3,501 3,605 3,261 3,439 3,471 3,596 3,525

40.0 I3031 43.014064 44.014095 42.01 4320 49.014350 41.5/BL-C(2) 43.5lH-335 46.5lH-360 49.01 H-414

3,710 3,696 3,902 3,560 3,773 3,642 3,619 3,699 3,907

37.01BL-C(2)

39.01H-335 44.011.1-360 40.011-1-414 51 .OIH-450

85 SIERRA SPITZER

36.013031 39.01 4064 39.01 4695 39.0 I4320 43.014350 35.5 IH -335 42.01H-380 44.01H-414 40.01H-450 3,196 3,331 3,402 3,174 3,325 3,149 3,341 3,457 3,433 37.013031 41.014064 41.014095 41.014320 48.014350 30.01H-335 46.01H-360 47.01H-414 49.01H-450 3,191 3,374 3,431 3,250 3,462 3,203 3,445 3,447 3 3 17

105 SPEER ROUND NOSE

32.01 3031 33.01 4064 35.01 4095 35.0 I4320 39.014350 40.01H-360 41.01 H-414 44.01H-450 45.01H-4031 2,770 2,794 2,937 2,037 2,903 .32.013031 36.014064 37.014095 30.514320 41.014350 42.01H-300 43 .O IH -41 4 47.011.1-450 47.01H-4031 2,750 2,945 3,020 3,019 2,902 3,035 3,075 3,140 3,249

3,033

3,066 3,045 3,106

AVTRON K973 Chronograph, AVTRON screens at 20-feet spacing, muzzle 10-feet from start screen. Velocitles are 20-feet instrumental corrected to MV. All loads are maximum, and safe only for the rifles in which they were developed. Loads for the 6mm Swift should be cut at least 4.0 grains to give starting loads in rifles chambered for this cartrldge.

J ~ l y - A ~ g1976 ~st

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