Colt Government Model MK IV/Series 70 .45 ACP Custom 1911 with Bar-Sto Match Barrel, Bo-Mar-Style Sights, and Compensator (1981)
This late-production Colt Government Model MK IV/Series 70 is a custom .45 ACP 1911 built on a 1981 Colt with a 70B serial prefix. It features a Bar-Sto stainless match barrel, Bo-Mar-style adjustable rear sight in a proper BMCS cut, an installed bushing-style compensator, and thoughtful frame and control upgrades. Classic Series 70 rollmarks and a blued carbon-steel slide and frame round out a period-correct base with performance-focused enhancements.
Condition
Overall Condition: Fair condition, showing extensive signs of prior use and handling.
Bore Condition: Fair - Generally clean, some residue or smudges, slight corrosion.
Rifling: Fair Rifling - Worn rifling, slight loss of definition.
Specific Condition Notes: There is pitting and surface rust on the top of the slide. The grips show wear consistent with age. The compensator has deep scratches. The bore is bright and clean.
What’s Included
- 1x 7-round steel single-stack 1911 magazine with polymer base pad
- Bar-Sto .45 ACP stainless match barrel (installed; hood marked "BAR-STO 45 ACP")
- Bo-Mar-style low-mount adjustable rear sight in BMCS cut (installed)
- Pinned serrated front sight (installed)
- Full-length two-piece hex-head guide rod (installed)
- Beavertail grip safety (installed)
- Commander-style rowel hammer (installed)
- Hand-checkered front strap (frame work)
- 1911 bushing-style compensator (installed)
This Government-length Series 70 starts with a blued carbon-steel Colt slide and frame, classic Series 70 rollmarks, and rear vertical serrations. It is a late-production example with the 70B serial prefix and was manufactured in 1981 in the USA.
Performance upgrades center on a Bar-Sto stainless match barrel measuring 5.25 inches, with the hood correctly marked "BAR-STO 45 ACP." A full-length two-piece hex-head guide rod supports the short-recoil, single-action operating system. Capacity is 7+1.
Target-focused sights include a Bo-Mar-style low-mount adjustable rear installed in a BMCS cut, paired with a tall pinned and serrated front blade. This setup provides a precise sight picture appropriate for refined shooting.
Ergonomics and control enhancements include an extended beavertail grip safety, a Commander-style rowel hammer, a hand-cut checkered front strap, and a beveled magazine well. An arched, checkered mainspring housing and full-checkered wood grip panels complete the handling package. A 1911 bushing-style compensator is installed at the muzzle.
Factory-type safety features include a thumb safety and a grip safety, consistent with the 1911 platform.