With Colt NOTHING is 100% sure.
As to what specific year Colt made grips changes, even this is not certain, since Colt would show older or newer grips in their catalogs, and would often use up supplies of older styles even after they made a change.
Dates are ONLY estimates.
Here's the standard Colt Python grips, and "about" when they were used:
First type.
Fully checkered, made of walnut with a dull oil finish. Gold medallions ONLY on Pythons, other guns used Silver.
The same type of grip was also used on other Colt revolvers with Silver medallions, some of which were made of a hard wood with a very dark brown stain. Under the dark brown stain the wood is a yellow-white fairly soft hard wood. Watch out for medallions being switched.
Used from 1955 to around the early 1960's:
Second type.
"Half-moon" checkering border under the medallions, "thumb rest" (actually a speed loader cut) only on the left side. Made of walnut with a semi-gloss varnish type finish. Probably the most attractive Colt Target grip.
These also were made of a hard wood for other models of Colt's. These have a lighter, more natural walnut stain, but under the stain is the softer yellow-white hard wood, which has almost no grain.
Used from early 1960's to mid-1970's.
Third type.
Checkering ends in a slanted straight line under the medallions, "thumb rest" on both sides. Semi-gloss finish. The most copied type, replicas and fakes abound.
Used from mid-1970's to mid-1990's.
Fourth type.
No checkering, made of laminated wood that came in in several colors. Medallions may be Gold or Silver. Made by "Excaliber", an outside contractor.
Used from mid-1990's to end of production in 2003:
Service type.
The Colt Service type grips were used almost exclusively on the 2 1/2" Python, all others usually had Target grips.
These always had Gold medallions.
Rubber types.
Colt used Pachmayr "Presentation" square butt grips in both standard and a slightly smaller version from the early 1980's to sometime in the 1990's, usually on stainless guns but later on blued too.
They also used Pachmayr Grippers. All had Gold or occasionally Silver medallions.
For a short time in the 1990's Colt used Hogue rubber Mono-Grips with molded-in Colt logos.
Fakes and "replicas"
Italian made.
These are made of European walnut, and in a very poor European hard wood. The hardwood didn't have medallions and at one point were sold by CDNN for $9.95.
The better type with medallions may even be found in "Colt" wrap. No Python ever left the factory with these.
These are often found on Pythons up for sale, with the inference that they're original Colt grips.
Note the odd S&W style checkering with grooved border, the checkering ending farther up on the butt, the odd looking thumb rests. These are flatter on the sides than the more oval shaped Colt grips.
Note a common feature of fakes and replicas..... brass screws and screw bushings on both sides. Colt used only a single steel bushing on the right grips and steel screws. These are usually blued, but may be plated.
Cheap Italian hard wood fake by the same maker:
Current Asian "replicas".
These are made in Asia and heavily sold on Ebay among other sources.
These are usually made of Asian hard woods, often with garish contrasting grain. Checkering is often crudely done.
Note the odd non-Colt type thumb rests.
These usually have Gold medallions that appear to be the Colt Pony logo , but on closer inspection are not. Watch out for these medallions to be switched with real Colt medallions:
Second type fakes.
These are currently being sold heavily on Ebay, and are better then the Third type shown above. Again, medallions appear to be Gold Colt until you look closer.
