10.5" 458 SOCOM Stainless Bull AR15 Pistol Upper Assembly with 10" Rail and Competition Muzzle Break
The .458 SOCOM is a moderately large round designed for a specialized upper receiver that can be mounted on any AR-15 pattern lower receiver. The 300-grain round offers a supersonic muzzle velocity of 1,900 ft/s and 2,405 ft⋅lbf, similar to a light .45-70 but with a much smaller case. The cartridge case design was finalized based on discussions with Tony Rumore at Tromix.
- 10.5"458 SOCOM 416R Stainless Steel Bull Contour Barrel with 1x14 Twist and 5/8x32 Threads.
- Mil-Spec Upper Receiver forged from 7075 T6 aluminum with forward assist and dust cover assembly installed. Hard coat anodized MIL-STD 8625 Type 3 Class 2. Properly modified for the large bore 458 SOCOM cartridge with a single feed ramp and an enlarged ejection port.
- 10" Narrow Profile Free Float Rail machined from 6061 T6 aluminum. Very comfortable and very light weight. Your choice of M-LOK or KEYMOD attachment points along the entire length at 3, 6, and 9 positions. Hard coat anodized MIL-STD 8625 Type 3 Class 2.
- 0.875" Low Profile Gas Block.
- Pistol Length Gas System.
- Competition Muzzle Brake with crush washer.
- AR15parts will customize (to your specificaions in the drop down menu) your AR15 upper with the Rail Type (M-LOK or KEYMOD), a Magazine or two, one of our High Quality Bolt Carrier Groups, and your choice of 5 different Charging Handles.
458 SOCOM NOTES:
- BOLT/BCG: Reliable cycling and firing of 458 SOCOM ammunition is significantly improved by a high quality bolt desgned specifically for 458 SOCOM cartridges. The 458 SOCOM bolt included with our 458 SOCOM bolt carrier group (BCG) is specifically engineered with the critical features that ensure consistent performance of our 458 SOCOM upper assemblies.
- LOADING: Only load 458 SOCOM ammunition from a magazine. DO NOT load through the ejection port as a slam fire can occur upon bolt release.
- ALUMINUM GI MAGS ONLY: We only recommend and sell D&H Tactical Aluminium magazines for 458 SOCOM ammunition. Polymer magazines can swell or flex, creating opportunities for misfeeds, jams, and other issues that aluminum magazines eliminate.
This upper assembly will fit all standard AR15 lower receivers.
This item is "Firearm Parts", not a complete firearm (no serialized components). It will be shipped directly to you with no FFL transfer required.
You are responsible for knowing federal, state and local laws applicable to this item. AR15Parts.com reserves the right to not ship to addresses where it may not be legal to own this item.
Great WebsiteJeffrey Stills
Astounding ValueAs a gunsmith I've had many uppers come through and there's not many that would compare to the quality of materials and overall build quality anywhere near this price point. I'm only giving 4 stars because all I've done is examine the parts tolerances and overall assembly quality. I'm waiting on a LPK to finish the build up from a different vendor. My only gripe is the amount the handguard was cranked down to. I should've checked it for breakaway torque but I could tell just looking at it someone went a little nuts on it. I did do a small amount of work to clean up the feed ramp. By no means was it a problem, manually cycled and fed fine. I just wanted to ensure my brass stays useable as long as possible for reloading and it was a bit rough by my standards..
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DetailsCurrent Stock:SKU: UA45S10SS14B832P_10ML00_CBUPC:Availability: Usually Ships in 24 HoursOld SKU: 105458CMU1x1KMMLR