Not from WW II forward.

 

From the 1840's to WWII Colt made grips and stocks in their "furniture" department.
They made grips, stocks, and the massive display cases they used at the big world's fairs and industrial shows to display Colt firearms.

With WWII they began fitting pistols with grips made of early plastics, and when they resumed wood grips in the early 50's they were contracted out.

 

Also, Colt owned a plastics division.

They provided stocks for the WWII Commando and M1911A1.
In the early post war era, they provided stocks over the entire
revolver line and the Government Model.
This was approximately 1948-1954. Beginning in 1955 Colt reverted back to wood stocks, with the exception of
the Government Model. Colt continued to use plastic stocks on this pistol until the introduction of
the Series 70, at which time they switched to wood.

 

In my collection, I have a 22, 4" Trooper # 68573 (1968)?, with the small, wood, service stocks marked SILE inside. They are no doubt that they are original to the gun. Big Larry

 

Who made what when for Colt is murky at best.
No one was interested in who made Colt grips in those days and now no one is around who did know.

 

The Italian company Sile did make a large share of the "factory" revolver grips for Colt in the '60s and '70s.

 

Thanks for the info. My Trooper is considered scarce. I just bought it on a whim. I mostly collect S&W's, but recently switched over to M1911's and ACE's. Big Larry