7mm Remington Short Action Ultra Magnum

History

The 7mm SAUM was released in 2002 based on a shortened version of Remington's Ultra magnum case which is in turn based on the 404 Jeffery’s case. The SAUM was designed to produce 7mm Remington Magnum performance from a much smaller cartridge case and more compact rifle configuration.
In 2002, the same year as the introduction of the 7mm SAUM, Winchester released their own short magnum, the 7mm WSM. The two competing cartridges were presented to the market but only one survived- the 7mm WSM. Not only was the WSM more popular with hunters, the cartridge was soon adopted by several rifle manufacturers, ensuring its continuation.

Case capacity of the SAUM is slightly less than the WSM, as is the factory COAL. Remington adopted these dimensions to enable their short magnum cartridges to fit into the compact Model 7 action. Factory barrel length of the Model 7 is 22" as opposed to Winchester's short magnum barrels at 24”.
The 7mm SAUM currently retains a small following. This cartridge, chambered in the model 7 rifle, is appreciated for its ability to produce high power from a small, ultra-light weight platform.

Performance

The 7mm SAUM does not achieve 7mm Remington Magnum velocities or performance. This cartridge duplicates the velocities of the .280 Remington.

Factory ammunition

Remington loads include the 140 grain Core-Lokt Ultra at 3175fps, the 150 grain Core-Lokt at 3110fps and the 160 grain Core-Lokt Ultra at 2960fps. However, these velocities are taken from a 24" test barrel. Actual velocities in tested Model 7 rifles average around 3150fps with the 140 grain load, 2950fps with the 150 grain and 2850fps with the 160 grain load.

The 140 and 160 grain Core-Lokt ultra bullets produce similar terminal performance to other core bonded designs, delivering high shock and wide wounding at impact velocities above 2600fps and clean but often delayed killing as velocities approach 2400fps. At lover velocities, kills can be very slow. Unfortunately, the Core-Lokt Ultra bullets have very low BC’s of .409 and .414 and even the faster 140 grain bullet is down to 2600fps at just 225 yards.

The standard 150 grain Core-Lokt is an excellent performer on lighter medium game out to 200 yards. Beyond this range, as velocity falls below 2400fps, kills can be very slow due to narrow wounding.

Hand loading

The most suitable powders for hand loading the 7mm SAUM are those in the 4831, N165 range. Achievable velocities duplicate factory loads including 3150fps with 140 grain bullets, 2950fps with 150 grain bullets and 2850fps with 160-162 grain bullets.

References to bullet performance can be found in the .280 text of which the 7mmSAUM performs very similarly.

Closing comments

The differences between the 7mm SAUM and 7mm WSM in factory ammunition or hand loads average about 75fps in favor of the Winchester which is mostly relevant to the Winchester’s 2” longer barrel. However it is perhaps moot to draw comparisons between the two because the design concept behind the 7mm SAUM Remington is to offer an effective medium game hunting cartridge in an extremely efficient carbine for hunters who require the minimum of bulk and weight.

Suggested loads: 7mm SAUM					Barrel length:
No	ID		Sectional density	Ballistic coefficient	Observed MV Fps	ME Ft-lb’s
1	FL	Rem 140gr Corelokt	.238	.409	3150	3084
2	HL	139gr SST/IB/AB	.246	.486	3150	3062
3	HL	154gr SST/IB	.273	.525	2900	2875
4	HL	160gr Partition	.283	.475	2850	2885
5	HL	162gr A-Max	.287	.625	2850	2921

Suggested sight settings and bullet paths
1	Yards	100	160	287	327	350	375	400	425
	Bt. path	+3	+3.8	0	-3	-5.1	-7.8	-11	-14.5
2	Yards	100	165	294	335	350	375	400	425
	Bt. path	+3	+3.9	0	-3	-4.3	-6.8	-9.7	12.9
3	Yards	100	150	265	305	325	350	375	400
	Bt. path	+3	+3.6	0	-3	-4.8	-7.5	-10.6	-14.1
4	Yards	100	150	257	297	325	350	375	400
	Bt. path	+3	+3.5	0	-3	-5.9	-8.8	-12.2	-16
5	Yards	100	150	264	305	325	350	375	400
	Bt. path	+3	+3.6	0	-3	-4.9	-7.5	-10.6	-14

No	At yards	10mphXwind	Velocity	Ft-lb’s
1	300	6.6	2468	1893
2	300	5.4	2569	2036
3	300	5.6	2388	1949
4	300	6.4	2293	1868
5	300	4.7	2420	2107

	Imperial	Metric
A	.534	13.56
B	.550	13.97
C	30deg
D	.534	13.56
E	.320	8.12
F	1.538	39.06
G	.497	12.62
H	2.035	51.7
Max Case	2.035	51.7
Trim length	2.025	51.4