7mm Shooting Times Westerner

History

The 7mm STW was developed by Layne Simpson, gun writer for the Shooting Times Westerner magazine. Based on the 8mm Remington magnum case necked down to 7mm, Simpson’s goal was to drive 160 grain bullets at over 3200fps. In 1997 the 7mm STW was picked up by Remington who presented the first model 700 7mm STW to Simpson along with the first box of factory ammunition.

Following its introduction, the STW quickly gained popularity among hunters interested in open country hunting, mountain hunting and dedicated long range hunting enthusiasts. This success lasted for a few years but was interrupted after the release of the 7mm Remington Ultra Magnum in 2000. Before long the 7mm STW was abandoned as a factory chambering in favor of the hot new comer.

Today the 7mm STW retains a small degree of popularity. The STW is a highly potent but sometimes misunderstood cartridge.  
 

Performance

When Layne Simpson designed the 7mm STW the design was based around typical hunting bullet designs, utilizing minimum free bore. In other words, hand loaders could seat bullets to touch the lands with plenty of bullet left sitting in and below the case neck for optimum concentricity. With soft point bullets the maximum COAL is complimentary to the maximum internal magazine length of the M700 action. This design gave Simpson maximum potential from the M700 action. However, loaded with match style bullets for dedicated long range hunting, the maximum COAL is too long for the M700 rifle magazine (around 96.5mm or 3.800”). For those wishing to seat match style bullets close to the lands, a Wyatt extended box magazine must be fitted to the M700 action. Further complications arise in custom rifles which feature shorter magazines than the M700 platform. It is under these circumstances that the STW is often described as having long free bore when this is not actually the case. With the right magazine length, the STW can be loaded with soft point and match style bullets with full room for seating depth experimentation for extreme accuracy.
 
The 7mm STW is somewhat over bore in case capacity, a fact that can be seen by exploring the velocities of the 7mm Practical versus the STW, the STW struggling to gain any more velocity. Put simply, a 7mm bore can only produce so much velocity before the gains become very small, while throat erosion and therefore barrel life decreases accordingly. Nevertheless, the STW was never designed for high volume shooting. The STW achieves its velocity goals, achieving its design premise in spades to such an extent that it seems a great shame that Remington kicked the STW to the curb in favor of the 7mm RUM.

For high volume long range shooters, throat erosion is a negative of the STW. Barrel life for the STW is between 600 and 900 rounds depending on methods of use and cleaning procedures. With good throat polishing procedures and low volume shooting it is possible to push barrel life beyond 1000 rounds.
 
The STW represents the absolute maximum velocities obtainable from the 7mm bore. The 7mm RUM, though it uses greater powder charges, is not able to exceed the power of the STW. Slight differences do occur with long 32” barrels.
 
Loaded with 140 grain bullets driven at 3400-3500fps, the STW produces somewhat poor performance on light through to medium game. Surface bullet blow up and delayed killing is common with conventional soft point bullets. Premium bullets produce much more uniform results and wounds tend to be uniform.
 
150 grain bullets driven at 3300-3400fps in the STW produce much the same results as 140 grain bullets. Conventional bullet designs suffer a reduction in performance, only a few bullet designs produce desirable, uniform results across varied game weights and ranges.
 
The STW begins to come into its own when loaded with 160-162 grain bullets driven at  velocities of between 3200 and 3300fps. Some bullet designs continue to show weaknesses when used at close ranges but at longer ranges, performance can be very spectacular.
 
The 7mm STW is able to drive 175-180 grain bullets between 3100 and 3200fps. Ideal for light to medium weight game, reaching its limits but adequate for Elk sized game where long range hunting is a consideration. Clean kills can be produced as far as 1100 yards.

   

Factory ammunition

Remington currently list only two loads for the STW, a 140 grain Core-Lokt  and a 140 grain Swift A Frame, producing 3325fps (26” barrel). Both of these loads have BC's of under .4 limiting the long range performance of the big seven and are ‘token gesture’ loads for what is otherwise a hand loaders cartridge. These are however, acceptable lighter medium game loads.  The mild velocity of 3325fps as opposed to full velocities of 3450fps work to the strengths of Core-Lokt bullet design. Wounding and penetration are surprisingly good, if not spectacular.  The A-Frame is sound enough in construction to tackle very stout bodied medium game, producing uniform wounding and free bleeding exit wounds.

Federal  manufacture two loads for the STW, the 160 grain Sierra GameKing at 3200fps and 160 grain Trophy Bonded Bear Claw at 3250fps. Although true velocities of federal ammunition often falls well short of advertisements by 150 to 200fps. The GameKing is a fair performer, producing desirable performance on larger deer species at moderate to longer ranges of up to 600 yards. The TBBC produces deep penetration on Elk sized game, best utilized at close to moderate ranges to maximize disproportionate to caliber wounding. Used this way the TBBC produce violent, fast, emphatic kills.
 

Hand loading

The 7mm STW is a hand loaders cartridge. Brass is readily available from Remington and will most likely continue to remain in good supply for many years to come. The most suitable powders for the STW are the ultra slow burners including H1000, Retumbo, U.S 869 and similar burn rates.

Typical velocities to expect from a 26" barrel are over 3450fps with 140 grain bullets, 3350fps with 150 grain bullets, 3300fps with the Hornady 154 grain bullets, 3250fps with 160-162 grain bullets and 3150fps with 175-180 grain bullets. The STW is to some degree better served with a 28”barrel as well as a fatter contour barrel than the standard M700. As suggested in the performance section, the 7mm STW needs a long magazine, the M700 long action box magazine being ideal for general hunting bullets. If utilizing match style bullets, the hand loader has two options; seat to magazine length with a degree of bullet jump (very similar to the .308 Winchester) or have a Wyatt extended magazine box fitted to allow a full range of seating depth experimentation.

The ahead text will address projectiles that produce the most desirable results in the 7mm STW.

Hornady have some very useful projectiles that can be put to a wide range of tasks in the 7mm STW. The 154 grain SST and 154 grain InterBond are an excellent combination. These two projectiles can be used to great effect. The InterBond does its best work inside 400 yards and is an emphatic killer on medium game and can be used adequately on game up to the Size of Elk. For best results the InterBond should be annealed (see 7mm Rem Mag).

The SST tends to suffer a reduction in its ability to produce hydrostatic shock at impact velocities above 3200fps (point blank to 50 yards), gradually coming into its own at 3100fps (100 yards). The SST can be used on game weighing between 80 and 150kg at close ranges however penetration tends to be shallow. Once the 154 grain SST breaches the 3000fps mark, wounding on medium game is very uniform out to 750 yards (2000fps) and the SST will readily expand at velocities as low as 1600fps (1050 yards) without need of high resistance. 

One bullet that often gets passed over in favor of modern tipped bullet designs is Hornady’s traditional 162 grain BTSP Interlock. Not only is this bullet a good cheap practice load, its performance on game at STW velocities is outstanding. This bullet produces hydrostatic shock on light to medium weight game at impact velocities above 3200fps where other bullet designs and weights will not- and kills are spectacular. Furthermore, the Interlock is not so fussy to load for, accuracy is normally easy to obtain. BC of the 162 grain BTSP is only .514 but for the hunting of lighter medium game out to ranges of up to 700 yards, this is an inexpensive, no fuss option.

Hornady’s 162 grain SST is an outstanding bullet. To fully optimize performance, this bullet should be annealed, even if only a few are kept handy, rather than annealing every single projectile. Once annealed, the 162 grain SST tackles light through to large bodied game weighing 150kg (330lb) with ease. Like its 154 grain counterpart, this bullet suffers a reduction in the  ability to produce shock at impact velocities above 3200fps. Wounding at point blank ranges is thorough and violent - but slightly delayed on game of all weights. The 162 grain SST is an excellent long range hunting bullet, explosive on light game and particularly useful on heavy deer species at extended ranges of between 600 and 1000 yards.

The 162 grain Hornady A-Max is a spectacular long range hunting bullet. Unfortunately at closer ranges the A-Max can meet too much resistance and like the SST bullets just described, can fail to impart hydrostatic shock. In this instance however, killing can be more delayed than is usual, with animals walking or standing drunkenly for some time. Internal wounding is almost always extremely violent, yet animals remain standing for some time. In some instance, game are able to traverse and cover some distance before succumbing to blood loss. To this end, neck and head shots produce the best results at close ranges. The A-Max produces more uniform results and faster killing at 2900fps  or 225 yards. Performance at impact velocities of between 2600 and 2000fps (425-875 yards) is quite often spectacular with a maximum effective range of around 1100 yards or 1400fps.

The Speer 160 grain Hotcor and 160 grain BTSP can be quite useful in the ultra velocity sevens. Like the 162 grain Interlock, these projectiles are not usually fussy to work with. BC of the Hotcor is 504 and for the BTSP .519. The Hotcor is best suited to game weighing between 80 and 150kg (180-330lb) out to ranges of around 400 yards. The BTSP variant is fast expanding- a far softer bullet than the likes of the Nosler Ballistic Tip and is effective on light through to medium weight game, producing wide wounding out to ranges of around 850 yards.

Nosler’s 160 grain Partition is a dramatic and violent killer when loaded to 3250fps. The Partition has a low BC of .475 but remains an emphatic killer out at 550 yards (2200fps). Maximum effective range for the Partition is around 650 yards, after which, wounding deteriorates in the absence of high resistance. The 160 grain Accubond has a high BC of .531 and is effective general purpose hunting bullet. Exit wounds on light to medium weight game tend to be around 1” diameter rather than the 3”+ diameter exit wounds produced by conventional bullets as well as the Partition. The Accubond is to this end, a better meat retrieval bullet. Nevertheless, when used side by side with the Partition, one cannot help but fall for the performance of the older bullet design. The Accubond produces fast killing inside 350 yards (2600fps). Beyond this range kills are clean but can be slightly delayed.

The Swift 150 grain Scirocco has a long bearing surface which has a pronounced effect on barrel harmonics. This effect on harmonics can at times be used to ones advantage during hand load experimentation with finicky rifles. By the same token, results can be quite the opposite, such is the nature of rifle barrels at times. Wounds created by the Scirocco at ordinary hunting ranges (out to 300 yards) are more dramatic than Nosler’s 160 grain Accubond, mostly due to the lighter weight/ greater target resistance. The Scirocco loses a lot of weight and SD when used on tough medium game but it manages to penetrate through to offside hide. On lighter game, exit wounds are relatively wide. The Scirocco, like all core bonded designs, tends to lose the ability to initiate shock at impact velocities below 2600fps (375 yards) however killing is not quite as delayed at lower velocities as often occurs with other designs. This bullet is best suited to deer weighing up to 150kg (330lb). On tough animals such as wild Boar, 80kg (180lb) is a safe limit.

The 160 and 175 grain Swift A-Frame are emphatic killers on tough animals such as heavily shielded Boar and Elk. The 175 grain A-Frame (BC .493) can be relied on to produce fast killing on large bodied game out as far as 375 yards (2400fps).

The 160 and 175 grain Woodleigh Weldcore bullets are similar in performance to the A-Frame. I personally have a soft spot for these bullets and their suitability for tough animals. The Woodleigh produces a great deal of internal trauma when used at high velocity. These bullets are acceptable performers on light bodied game but in no way as spectacular as softer, more conventional bullet designs.

The 168 grain Berger VLD can be very useful in STW once annealed (see annealing tutorial). Effective range is around 1000 to 1100 yards and is best suited to game weighing up to 150kg (330lb). The 180 grain Berger VLD can also be very useful on larger bodied medium game out to identical ranges (1800fps) after annealing. From a muzzle velocity of 3150fps, the 180 grain VLD (BC .684) crosses the 2000fps barrier at around 900 yards. Beyond this range, speed of killing can be very much dependent on point of impact. Rear lung shots may produce little to no reaction whatsoever, therefore it is important to have a spotter observe shots.
 
One of the most recent new comers to the long range game is the 190 grain Matrix bullet. Loaded to 3000fps this can make for a good all-around heavy weight fragmentary bullet, capable of tackling light through to larger bodied game out to ranges of around 1000 yards.
 

Closing comments

I am not completely sure - but I believe that Layne Simspon was not a long range hunter when he designed the 7mm STW. If I am correct, he was an open country hunter who wanted a cartridge with an ultra flat trajectory, capable of taking down game at extended ranges without dial capable optics and drop charts. The Weatherby cartridges were born under similar circumstances. But as long range optics, laser range finders and supporting information became more readily available, the STW was in a very good position to excel within this role due to the thought put into it during the design phase.

Beyond its potential increase in barrel wear, it is hard to fault the STW. This cartridge can be used for general mountain hunting of mid weight game species or it can be utilized as a dedicated or specialized long range tool. But either way, the STW rifle and its loads must be set up carefully in order to achieve the accuracy required to connect with game at extended ranges. Power that cannot be harnessed with accuracy is utterly pointless as is power that cannot be transferred to game due to the use of a poor bullet design. All of these things must work together.  

At this time of writing, Remington no longer produce 7mm STW rifles, favoring the 7mm RUM due to customer demand for non-belted magnums. It seems that we gave up the belt for radical free bore.

 

Suggested loads: 7mm STW					Barrel length:26”
No	ID		Sectional Density	Ballistic Coefficient	Observed  MV Fps	ME Ft-lb’s
1	FL	Fed 160gr Gameking	.283	.455	3200	3637
2	HL	154gr SST/IB	.273	.525	3300	3723
3	HL	160gr Speer Hotcor	.283	.504	3250	3752
4	HL	160gr Speer BTSP	.283	.519	3250	3752
5	HL	162gr Interlock	.287	.514	3250	3799
6	HL	162gr A-Max	.287	.625	3250	3799
7	HL	168gr VLD	.298	.643	3200	3819
8	HL	180gr VLD	.319	.684	3150	3965
9	HL	180gr VLD *	.319	.684	3150	3965

 
 

Suggested sight settings and bullet paths
1	Yards	100	165	298	339	375	400	425	450
	Bt. path	+3	+3.9	0	-3	-6.4	-9.2	-11.7	-15.9
2	Yards	100	175	316	358	375	400	425	450
	Bt. path	+3	+4.1	0	-3	-4.4	-6.8	-9.5	-12.5
3	Yards	100	160	308	350	375	400	425	450
	Bt. path	+3	+4	0	-3	-5.2	-7.8	-10.7	-14
4	Yards	100	160	309	352	375	400	425	450
	Bt. path	+3	+4	0	-3	-5.1	-7.1	-10.5	-13.7
5	Yards	100	160	309	352	375	400	425	450
	Bt. path	+3	+4	0	-3	-5.1	-7.7	-10.5	-13.8
6	Yards	100	175	316	359	375	400	425	450
	Bt. path	+3	+4.1	0	-3	-4.3	-6.7	-9.3	-12.3
7	Yards	100	175	310	352	375	400	425	450
	Bt. path	+3	+4	0	-3	-4.9	-7.3	-10.1	13.2
8	Yards	100	175	305	348	375	400	425	450
	Bt. path	+3	+4	0	-3	-4.9	-7.9	-10.7	-13.8
9	Yards	100	175	312	354	375	400	425	450
	Bt. path	+3	+4.1	0	-3	-4.8	-7.3	-10	-13.1

 
 

No	At yards	10mphXwind	Velocity	Ft-lb’s
1	300	5.7	2582	2369
2	300	4.7	2742	2570
3	300	5	2676	2544
4	300	4.9	2692	2574
5	300	4.9	2687	2597
6	300	4	2781	2782
7	300	3.9	2749	2818
8	300	3.8	2729	2977
9	300	3.8	2729	2977

 
Note: These tables for standard scope height 1.6”.  *An example of scope height set to 1.8”.
 
 

 

	Imperial	Metric
A	.532	13.51
B	.532	13.51
C	25deg
D	.487	12.36
E	.317	8.05
F	2.389	60.68
G	.278	7.06
H	2.850	72.39
Max Case	2.850	72.39
Trim length	2.840	72.1

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