January 04, 2011
By Layne Simpson
The search for a Bigger Seven opened the door for a family of magnum cartridges.
By Layne Simpson
All things--including chamber pressure, barrel length and bullet weight--being equal, the ST family is usually about 200 fps faster than shorter cartridges of the same caliber. From left to right: .257 STW, .257
Weatherby Magnum, 6.5mm STW, .264 Winchester Magnum, 7mm STW, 7mm Remington Magnum, .358 STA, .358 Norma Magnum.
One day back in 1979 when the 8mm Remington Magnum had been with us for a bit less than two years I decided, just for the fun of it, to neck the new case up and down to various calibers. Realizing that the .338-caliber version would do no more than duplicate the performance of an existing factory cartridge called the .340 Weatherby Magnum, I quickly lost interest in it.
Nowadays the author hunts more with the 6.5mm STW than with any other cartridge in the STW family and took this black bear with a rifle in that chambering.
At the time, the 7mm version seemed to make the most sense for several reasons, one being the fact that the popular 7mm Remington Magnum and 7mm Weatherby Magnum cartridges were on the shortened Holland & Holland belted case, while our most popular rifles, the Winchester Model 70, Remington Model 700 and Weatherby Mark V, were quite capable of handling cartridges on the full-length case.
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Since the cartridge I had in mind was on a Remington-designed case and since it was bound to be faster than the short 7mms, I decided to call it the 7mm Remington Maximum.
Rifles in 7mm STW, from left to right: Jarrett custom Model 700 (first rifle built in 7mm STW), Webernick custom Model 700 (six pounds with scope), Winchester M70 Sporting Sharpshooter by USRAC Custom Shop.
At the time, powders of super-slow burn rates that would be required in order to reach maximum velocities in the cartridge were quite scarce, and for this reason the new wildcat remained nothing more than an idea for several years.
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My interest in the Bigger Seven project was renewed in 1986 when DuPont finally got around to making available to the canister trade an old, slow-burning propellant called IMR-7828. Up until that time it had been available only to commercial ammunition manufacturers for use in the .264 Winchester Magnum and 7mm Remington Magnum.
During that same year Bob Hodgdon informed me that H5010, a military surplus powder originally developed by DuPont for the .50 BMG cartridge, was available from his company and a supply was headed my way. Not long after that Hodgdon introduced another slow-burner called H1000, and soon thereafter Hercules (now known as Alliant) introduced Reloder 22. It was time to see how fast the big cartridge could run.
Kenny Jarrett put together the very first rifle in 7mm STW in 1987. Built on a blueprinted Remington 700 action, it has a 25-inch Hart barrel with a 1:10-inch twist and a McMillan fiberglass stock with that company's wood-grain finish. I have not kept an accurate record of how many rounds I have fired in that rifle but am sure it is more than 1,000, and it still averages less than an inch at 100 yards.
When new, it averaged less than a half-inch with the Nosler 140-grain Ballistic Tip. The rifle still wears the same 2.5-10X Schmidt & Bender I installed on it the day I got it. Its weight of 93?4 pounds makes it a bit much for toting up a sheep or goat mountain, but it is ideal for sitting in one spot and shooting away over yonder, which is mostly what I have used it for.
Shortly before Jarrett had completed the rifle I decided to change the name of the cartridge to 7mm Shooting Times Westerner, or 7mm STW for short, and it stuck. My first article on the new cartridge was published in Shooting Times in 1988, and to simply say that it took off like a scalded dog among hunters across the country would be an understatement of the facts.
OTHER MEMBERS OF THE FAMILY
My first store-bought deer rifle was a Marlin 336 in .35 Remington, and I liked the caliber so much that I eventually got around to hunting with rifles in .358 Winchester, .35 Whelen and .358 Norma Magnum. After using a rifle chambered for the latter cartridge on a moose hunt in Sweden, I decided to neck up the 8mm Remington case to .358 caliber and call it the .358 Shooting Times Alaskan. Kenny Jarrett built the first rifle in that chambering for Bob Nosler and I got the second one, a switch-barrel Model 700 with its other barrel in 7mm STW. A few months later I headed to Alaska, where I bumped off a brown bear with the 250-grain Nosler Partition loaded to 3,000 fps.
I introduced the .358 STA to the world in 1992. Unlike the .257 STW and 6.5 STW, which are nothing more than the 7mm STW case necked down with the original body taper and shoulder angle retained, the .358 STA is the 8mm Remington Magnum case necked up and fire-formed to minimum body taper and a 35-degree shoulder angle. Cases can also be formed by necking down and fire-forming the .416 Remington Magnum case. When both are loaded to maximum chamber pressure with 250-grain bullets, the .358 STA is about 200 fps faster than the .358 Norma Magnum. It pretty much duplicates the performance of the 1920s-vintage .350 Griffin & Howe Magnum and the .350 Super Magnum, which was introduced by Art Mashburn during the 1940s. All are on the full-length Holland & Holland belted case.
At that point I had no intention of adding additional members to this particular wildcat family, but letters from readers who requested cartridges of other calibers eventually caused me to introduce the .257 STW in 1998. Lex Webernick built the rifle, and I first used it and a handload with the Nosler 100-grain Ballistic Tip at 3,700 fps to take a nice Coues deer down in Old Mexico.
About a year later I came up with the 6.5 STW, not because it had received a great number of votes from readers but because I was quite interested in that particular bullet diameter. The first rifle in that chambering was built by the Canadian firm Prairie Gun Works, and the first game I took with it was a black bear on Vancouver Island. The handload I used pushed along the Nosler 140-grain Partition at close to 3,200 fps.
When both are loaded to the same chamber pressures and fired in barrels of the same len
gth, I find the .257 STW to be about 200 fps faster with all bullet weights than the .257 Weatherby Magnum. I also find the 6.5 STW to be about 200 fps faster than the .264 Winchester Magnum. Whether that much gain in bullet speed is worth the effort is for the fellow who will be spending his own money for a new rifle to decide.
At first, top management at Remington had no interest in the 7mm STW because as they saw it, a factory-loaded version would spell doom for the 7mm Remington Magnum. Decision-makers at Winchester Ammunition gave it an even colder shoulder because they feared that other shooting publications would ignore it since its name contained the words "Shooting Times." (Shooting Times is now a sister InterMedia Outdoors publication of RifleShooter .--Ed.)
Kenny Jarrett built the very first rifle in 7mm STW in 1987, and it still averages less than minute-of-angle accuracy.
The chaps at Remington eventually changed their minds, and why they did is one of my favorite parts of the story. At the time, the 8mm Magnum was a dead duck; Remington had dropped it from the Model 700 rifle, and ammunition sales had become practically nonexistent. Then suddenly, orders for thousands upon thousands of rounds of 8mm Magnum unprimed brass began to pour in from distributors across the country. As Remington's investigation revealed, all those cases were being sold to handloaders who owned rifles in 7mm STW.
A sampling of some excellent powders for the entire STW family.
One of the reasons the 7mm STW became so successful so quickly was the fact that the chamber of any rifle in 7mm Remington Magnum could be reamed out for it. One gunsmith who charged $60 for a rechamber job (and who wisely ran advertisements in the issue of Shooting Times in which my first article on the cartridge appeared) told me that within 12 months after my first article was published he had rechambered more than 600 rifles from 7mm Remington Magnum to 7mm STW. That was from only one among dozens of gunsmiths across the country who were offering the same service.
Soon after Remington woke up to the fact that rifles in 7mm STW would sell, the wheels of progress began to pick up more speed. Then in a ceremony held during the 1997 NRA annual meetings, I was presented with the very first production rifle built in 7mm STW. I also received the first box of 140-grain Core-Lokt ammunition to come off the production line.
The 7mm STW is a descendent of the 8mm Remington Magnum; RCBS made the first set of reloading dies.
That first load offered by Remington was rated at 3,325 fps, but, as many of us eventually discovered, it exceeded 3,400 fps in some rifles with 26-inch barrels. Twelve months later Remington had sold just over 600,000 rounds of 7mm STW ammo, something I used to take great joy in mentioning to my friends at Winchester who had turned down the opportunity to beat their competition to the punch.
7mm STW LOAD DATA
BULLET
POWDER
VELOCITY
DATA SOURCE
(Type)
(Grs.)
(Highest Velocity Loads Listed)
Hornady 100-gr. HP
RL-22
83.6
3,800
Hornady
Barnes 100-gr. XBT
RL-22
81.0
3,634
Barnes
Sierra 120-gr. SPT
V-N 160
78.0
3,600
Sierra
Barnes 130-gr. XBT
H4831
79.0
3,523
Barnes
Sierra 130-gr. MK
RL-22
80.0
3,600
Sierra
Barnes 140-gr. XFB
IMR-7828
80.0
3,473
Barnes
Nosler 140-gr. Part
RL-22
82.0
3,382
Lyman
Nosler 140-gr. B-Tip
RL-22
79.0
3,410
A-Square
Sierra 140-gr. SPT
IMR-7828
79.0
3,400
Sierra
Barnes 150-gr. XBT
H-1000
81.0
3,359
Barnes
Nosler 150-gr. B-Tip
AA-8700
92.0
3,300
Nosler
Sierra 150-gr. SBT
H870
91.0
3,350
Sierra
Barnes 160-gr. XFB
H1000
80.0
3,287
Barnes
Nosler 160-gr. Partition
IMR-7828
78.5
3,272
A-Square
Sierra 160-gr. SBT
H870
88.4
3,250
Sierra
Barnes 160-gr. XLCFB
N-MRP
79.0
3,384
Barnes
Nosler 175-gr. Partition
AA-8700
89.0
3,047
Nosler
Sierra 175-gr. SBT
H870
86.3
3,100
Sierra
Speer 175-gr. GS
AA-8700
90.0
3,083
Lyman
Barnes 190-gr. Orig.
IMR-7828
75.0
3,127
Barnes
Other companies besides Remington also played important roles in the success of the 7mm STW. About four years before Remington adopted it, the custom shop of U.S. Repeating Arms began to offer Winchester Model 70 rifles chambered for it. That made the Model 70 one of very few factory rifles to ever be offered in a wildcat chambering. During a private meeting with USRAC officials in 1993 I was told about a yet-to-be-announced custom variation of the Model 70 and was asked to come up with a name for it.
The new rifle would be built for big-game hunting and it would wear a Schneider match-grade barrel, so I casually mentioned that "Sporting Sharpshooter" would be an appropriate name for the rifle. Shortly after that meeting took place I received the very first Model 70 Sporting Sharpshooter built by USRAC. Even more surprising was "7mm STW" engraved on its barrel. From that day on, the 7mm STW chambering was on the custom shop's list of options.
The next event that went a long way toward greasing the wheels of progress for the 7mm STW was the 1994 introduction of custom-loaded ammunition by A-Square. During a factory visit with Art Alphin, who owned the company at the time, I was asked which bullets should be offered. Soon thereafter I received a batch of the ammo, and the 140-grain load clocked an average of 3,437 fps when fired in my rifle. The 160-grain load averaged just under 3,200 fps.
A good 160-grain bullet is hard to beat for all-around use of the 7mm STW on game ranging in size from deer to elk.
So while Remington must be given a lion's share of credit for the success of the 7mm STW, we must not overlook the fact that Winchester was chambering custom rifles for it and A-Square was making the ammunition before Remington got around to adopting it. After Remington made an honest cartridge out of the 7mm STW, Winchester, Weatherby, Sako, Ruger, Tikka, Savage and possibly others also started offering rifles chambered for it. Federal, Winchester and Speer (under the Nitrex label) started loading the ammo.
These days you are more likely see me in the field with the 6.5 STW, mainly because I have come to appreciate that bullet diameter, but I still sometimes hunt with rifles in 7mm STW. In addition to that first Jarrett rifle, the Model 700 Sendero given to me by Remington and the Winchester Model 70 Sporting Sharpshooter I mentioned earlier, my battery contains a lightweight rifle built on the Model 700 action by Lex Webernick that weighs six pounds with scope. It is actually one of three matching Webernick rifles I own, the other two in .257 STW and 6.5 STW. I also have a Ruger No. 1 that was rechambered from 7mm Remington Magnum.
Right from the start the Nosler 140-grain Ballistic Tip proved to be the most accurate bullet in my Jarrett rifle. I have taken quite a few whitetail deer and pronghorn antelope at longish ranges with that bullet and have even used it to bump off a caribou or two, but it is too soft to use on larger game, so for elk I settled on tougher 160-grain bullets such as the Nosler Partition and Swift A-Frame.
As I grow older I tend to keep life more simple by using a good 160-grain bullet on everything from mice to moose. The 160-grain Nosler AccuBond is also an excellent choice, and a friend of mine is convinced that elk-bullet evolution ended with the Barnes X-Bullet of that weight. When loaded to 3,200 fps and zeroed three inches high at 100 yards, either of those bullets is just about dead on the money at 300 yards and less than a foot low at 400 yards, where it is still packing more than 2,000 ft-lbs of punch. A 140-grain bullet at about 3,400 fps shoots a bit flatter, but not by enough to really matter and it is nowhere near as versatile.
From the very beginning the Nosler 140-grain Ballistic Tip was the most accurate bullet in the author's first 7mm STW rifle.
As for factory ammo, I really like Remington's loading of the 140-grain Core-Lokt for deer and Federal's Premium loading with the Nosler 160-grain AccuBond for all-around use on everything from pronghorn and deer to moose and elk.
6.5 STW LOAD DATA
BULLET
POWDER
VELOCITY
DATA SOURCE
(Type)
(Grs.)
Sierra 85-gr. HP
IMR-7828
85.0
4,016
L. Simpson
Nosler 100-gr. Partition
H1000
88.0
3,863
L. Simpson
Speer 120-gr. SP
H1000
83.0
3,511
L. Simpson
Nosler 125-gr. Partition
AA-8700
91.0
3,515
L. Simpson
Swift 130-gr. Scirocco
H50BMG
88.0
3,461
L. Simpson
Nosler 140-gr. Partition
AA-8700
90.0
3,316
L. Simpson
.257 STW LOAD DATA
BULLET
POWDER
VELOCITY
DATA SOURCE
(Type)
(Grs.)
Hornady 75-gr. HP
RL-22
85.0
4,036
L. Simpson
Nosler 85-gr. B-Tip
RL-22
83.0
3,914
L. Simpson
Nosler 100-gr. Partition
H1000
86.0
3,709
L. Simpson
Nosler 115-gr. B-Tip
AA-8700
92.0
3,546
L. Simpson
Sierra 117-gr. SBT
AA-8700
89.0
3,507
L. Simpson
Nosler 120-gr. Partition
H1000
82.0
3,466
L. Simpson
.358 STA LOAD DATA
BULLET
POWDER
VELOCITY
DATA SOURCE
(Type)
(Grs.)
Barnes 180-gr. XFB
RL-19
95.0
3,357
Barnes
Barnes 200-gr. XFB
IMR-4831
90.0
3,217
Barnes
Nosler 225-gr. Partition
H4350
87.0
3,182
Hodgdon
Barnes 225-gr. XFB
IMR-4831
87.0
3,128
Barnes
Barnes 250-gr. XFB
IMR-4831
86.0
2,995
Barnes
Nosler 250-gr. Partition
H4350
89.0
2,981
L. Simpson
A-Square 275-gr. LL
H4831
90.0
2,857
A-Square
NOTES: All powder charges are maximum and should be reduced by 12 percent for starting loads. Cases for .257 STW and 6.5 STW formed by necking down Remington 7mm STW brass; .358 STA case formed by necking up 8mm Remington Magnum brass and fire-forming with a reduced powder charge. All rifles had 26-inch barrels.
I have lost count of those who have taken the time to write through the years to tell me how pleased they are with the accuracy of their rifles in 7mm STW. Many of the rifles had been rechambered from 7mm Remington Magnum, and the accuracy of a very large percentage improved dramatically after their rechamber jobs.
Remington's first 7mm STW factory ammo was loaded with the 140-grain Core-Lokt bullet, and it often exceeded 3,400 fps in 26-inch barrels.
Most who saw the sizes of their groups shrink assumed that it was due to the 7mm STW being a more accurate cartridge than the 7mm Remington, and while that may very well be true I have my doubts. Rather, I tend to believe that the improvement in accuracy was most often due to more concentric chambers cut by the gunsmiths who rechambered their rifles.
I still receive a good bit of mail from fans of the 7mm STW, but it has now lost a great deal of the momentum it once enjoyed. Remington stopped promoting it soon after introducing its own 7mm Ultra Mag, and not long after that the super-short magnums came along to steal even more of its thunder. Most companies no longer chamber standard-production rifles for it, and few writers (including this one) even bother to mention it anymore. But one thing is certain: The 7mm Shooting Times Westerner was a fun ride while it lasted.
WARNING: The loads shown here are safe only in the guns for which they were developed. Neither the author nor Primedia assumes any liability for accidents or injury resulting from the use or misuse of this data. Shooting reloads may void any warranty on your firearm.