458 SOCOM vs 45-70 compares two cartridges that fire the same .458-inch bullet from very different cases. The 45-70 Government is a long, rimmed case from 1873 that runs in single shots and lever actions. The 458 SOCOM is a short, rebated-rim case designed in 2000 by Marty ter Weeme of Teppo Jutsu to fit the AR15. Chattahoochee Munitions manufactures 458 SOCOM XL ammunition, a 650 gr subsonic loaded beyond the AR15 limit, along with the CM7S bolt action and CM10 semi-automatic firearms configured for it.
458 SOCOM vs 45-70 at a Glance
| 458 SOCOM (AR15 length) | 458 SOCOM XL (Chattahoochee Munitions) | 45-70 Government | |
|---|---|---|---|
| Bullet diameter | .458 in | .458 in | .458 in |
| Case length | 1.575 in | 1.575 in (standard 458 SOCOM case) | 2.105 in |
| Maximum overall length | 2.260 in | 2.802 in (CM7S), 2.790 in (CM10) | 2.550 in |
| Rim | Rebated, .473 in | Rebated, .473 in | Rimmed, .608 in |
| Typical firearms | AR15 | CM7S short-action bolt action, CM10 AR10-pattern semi-auto | Single shots, lever actions |
| Magazine | AR15 box magazine | Modified MDT metal AICS-pattern, 7 rounds | Tube magazine (lever) or none |
| Representative load | 300 gr at about 1,900 fps | 650 gr subsonic at about 1,010 fps (12.5-inch barrel) | 405 gr at about 1,350 fps (original), 300 gr at about 2,000 fps (modern) |
458 SOCOM vs 45-70: Same Bullet, Different Cases
Both cartridges fire .458-inch bullets, so the same projectiles fit either one. The difference is the case. The 45-70 case is about half an inch longer, so it holds more powder and can drive heavy bullets faster in a strong action. The 458 SOCOM case is short and uses a rebated rim that matches an AR15 bolt face, so it fits a detachable box magazine and a semi-automatic action.
The 45-70 also carries pressure limits from its history. Ammunition sold for older rifles is loaded to low pressure, and higher-pressure loads are only for modern, strong actions.
Where 458 SOCOM XL Fits in 458 SOCOM vs 45-70
Standard 458 SOCOM is limited to 2.260 inches overall to fit the AR15, which forces long, heavy bullets deep into the case. 458 SOCOM XL moves past that limit: Chattahoochee Munitions loads a 2.035-inch, 650 gr Maker REX in factory-new Starline brass to 2.802 inches for the CM7S and 2.790 inches for the CM10. Seating the projectile less deeply reclaims case capacity, and the result is about 1,473 ft-lb at the muzzle from a subsonic load.
That puts a bullet heavier than common 45-70 loads into a short action or an AR10-pattern rifle that feeds from a detachable magazine. For subsonic use, a large case is not an advantage: a subsonic load needs only enough powder to reach about 1,000 fps, and a shorter case suits that.
458 SOCOM vs 45-70 for Subsonic and Suppressed Shooting
Subsonic is where the two diverge most. A heavy subsonic bullet carries its energy through weight, not speed. The Chattahoochee Munitions 650 gr load averages about 1,010 fps from a 12.5-inch CM7S barrel and about 1,012 fps from a 12.5-inch CM10, staying below the speed of sound even at 0°F. Both platforms run a 1:10 twist to stabilize that long bullet; CM7S barrels are made by Mos-Tek from 416R stainless steel.
With subsonic ammunition, use an enclosed suppressor on both the CM7S and the CM10. The 12.5-inch CM7S is also offered with the PLACID OTB, an all-titanium over-the-barrel suppressor that keeps the suppressed firearm short. Read the 458 SOCOM suppressor guide for more.
458 SOCOM vs 45-70 for Hunting
Both are big-bore hunting cartridges for hogs, deer, and bear at moderate distances. Supersonic 45-70 loads shoot flatter than a subsonic 458 SOCOM load. The 650 gr 458 SOCOM XL load carries about 1,342 ft-lb at 100 yards and drops about 36 inches at 200 yards from a 100-yard zero, so it suits known, moderate distances. Its advantage is a quiet suppressed shot from a short, modern action with a detachable magazine. See 458 SOCOM ballistics for the full table.
458 SOCOM vs 45-70: Which Should You Choose?
- Choose 45-70 for a lever action or single shot, and for supersonic loads at the higher velocities a longer case allows.
- Choose 458 SOCOM XL for suppressed subsonic shooting from a 12.5-inch or 16-inch bolt action or AR10-pattern semi-auto with a detachable magazine.
Compare the two platforms in 458 SOCOM bolt action vs semi auto, and see every configuration on Terminal 458.
458 SOCOM XL Firearms for Shooters Weighing 458 SOCOM vs 45-70
Chattahoochee Munitions manufactures complete factory firearms chambered in 458 SOCOM and configured for 458 SOCOM XL:
- CM7S 458 SOCOM 12.5-inch SBR with PLACID OTB
- CM7S 458 SOCOM 12.5-inch bolt action pistol or SBR
- CM7S 458 SOCOM 16-inch bolt action rifle
- CM10 458 SOCOM 12.5-inch semi-automatic SBR
- CM10 458 SOCOM 16-inch semi-automatic rifle
458 SOCOM vs 45-70 FAQ
Is 458 SOCOM the same as 45-70?
No. Both fire .458-inch bullets, but the 45-70 case is 2.105 inches long and rimmed, while the 458 SOCOM case is 1.575 inches long with a rebated rim.
Do 458 SOCOM and 45-70 use the same bullets?
Yes. Both use .458-inch bullets. Overall length and the firearm’s magazine decide which bullets can be loaded.
Is 458 SOCOM more powerful than 45-70?
Not in general. The longer 45-70 case holds more powder, and full-pressure 45-70 loads in strong actions exceed AR15-length 458 SOCOM. In subsonic loads, bullet weight matters more than case size, and the 650 gr 458 SOCOM XL load produces about 1,473 ft-lb.
Can 458 SOCOM run a 650 gr bullet?
Yes, as 458 SOCOM XL. Chattahoochee Munitions loads the 650 gr Maker REX to 2.802 inches for the CM7S and 2.790 inches for the CM10, beyond the AR15’s 2.260-inch limit.
Which is better for a suppressor, 458 SOCOM or 45-70?
For suppressed subsonic shooting, 458 SOCOM XL in a short bolt action or AR10-pattern rifle suits the job, and with subsonic ammunition an enclosed suppressor is recommended.
Who makes a 458 SOCOM bolt action rifle?
Chattahoochee Munitions manufactures the CM7S 458 SOCOM bolt action with 12.5-inch and 16-inch barrels, plus a 12.5-inch SBR with the PLACID OTB suppressor, all configured for 458 SOCOM XL.
Is 458 SOCOM or 45-70 better for hogs?
Both work at moderate distances. 458 SOCOM XL adds a quiet suppressed shot and a detachable magazine, and the CM10 adds semi-automatic follow-up shots.