Colt MK IV Series ’70 Government Model .45 ACP – Custom Upgrades –
This is a recently acquired, customized Colt Government Model .45 ACP, part of the MK IV Series ’70 line
produced from 1970–1983, distinguished by the split collet barrel bushing for enhanced accuracy. Serial 70G37007, places it squarely in the 1973
production run.
It features several premium upgrades:
Full Long Side with no left side markings - right side is very faintly marked "COLT GOVERNMENT MODEL"
Frame marked by "Smith's Gunsmithing San Bruno Cal" -
Stamping is an indication of work performed, such as timing adjustments, fitting, or safety installations by a licensed gunsmith.
Bo-Mar full length rib
Bo-Mar adjustable rear sight
– highly respected for precision shooting
Patridge-style front sight
– improves precise sight picture
Skeletonized trigger
– reduces weight and enhances feel
Custom stippled front strap
– adds secure grip and control
Checkered wood grips
with silver eagle SILE medallions
Mechanically fine-tuned and still shooter-ready, with a bright, clean barrel
Specifications
Manufacturer:
Colt
Model:
MK IV Series ’70 Government Model Per Colt Serial Number Lookup - Unmarked
Caliber:.45 ACP
Capacity:
7+1
Barrel Length:
5-7/8″
Slide Length:
8-1/2"
Finish:
Blued
Sights:
Bo-Mar adjustable rear + Patridge front blade
Trigger:
Skeletonized for reduced weight
Serial Number:
70G37007 (1973)
Condition:
Good/shooter-ready – bright bore, heavy-duty frame, ready to perform
Historical Background & Significance
Series ’70 Colts
introduced the split collet barrel bushing for better lockup and accuracy—a defining feature of this series.
Production ran from 1970 to 1983, with this serial prefix 70G
confirming 1973 manufacturing
The Bo‑Mar adjustable sight is a hallmark of target-grade or custom 1911s and retains market desirability
Condition Summary
This pistol is in good condition
with typical wear from use and handling. The barrel remains bright and clean.
The frame and slide are blued with a nice vintage plum patina on the slide. Custom stippling to the front strap ensures a strong but comfortable grip.
FFL Required
An FFL is required for shipment. Please email a copy of your FFL with the product name in the subject line to: info@tylergunworks.com
