Blued Old Armys had alloy grip frames with standard skinny triggers until 1985. Then Ruger used blued steel grip frames with a wide slot and the wide SBH trigger, but smooth, not serrated.
I put this together for questions such as yours:
COMPLETE OLD & NEW MODEL REGULAR PRODUCTION USAGE INCLUDING SIZE, OF BLUE STEEL GRIP FRAME VS. ALUMINUM ALLOY, and USAGE OF STEEL VS. ALUM EJECTOR ROD HOUSING:
(Updated 2016)
Note: Ruger refers to their blue steel grip frames as alloy steel in their catalog, meaning Chrome Molybdenum (Chromoly) as opposed to alum alloy and stainless steel grip frames.
Blue steel GFs* on the following models:
All New Model Flat Top Blackhawk mid and large size cylinder frames.
All New Vaquero mid & large size cylinder frames, XR3 size (also cut for indexing pawl system, no extensions into main frame & only 7/16" thick).
All original large frame Vaqueros, XR3-RED size.
All Super BHs old and new models, XR3-RED size on short brl. lengths; Dragoon frames with 7 1/2" & 10" barrels.
All .32 Mag Vaq. style single sixes, SHORT grip & XR3-RED size.
Old Army beginning 1985, # XRN-3.
All Bisley and Birdshead grip frames.
All "Super" Bearcat old models introduced in 1971, have steel frames.
All new model Bearcats introduced in 1993, have steel frames.
Aluminum alloy grip frames on the following models:
All blue Super Single Sixes 22 and 32, XRE-RED size.
All large size cyl frame NON-flat top Blackhawks, XR3-RED size.
All Old Models, # XR3, pre 1963.
All Old Models 1963 to 1973, # XR3-RED, including Hawkeye single shot.
Old Army # XR3-RED, pre 1985.
All Old Model Bearcats prior to the Super Bearcats have alum alloy frames.
Steel ERH* on the following models:
All pre c. 1962 old models including Bearcats; new model Super BHs since c. 1999 in all barrel lengths (including 5" ERH on 44 & 357 Max 10" barrel).
Original Vaquero large frames post c. 1999.
All New Vaqueros and .32 single six 'Vaqueritos'.
All New Model Flat Top Blackhawks.
Alloy ERH on the following models:
All old models with alloy grip frames post 1962.
Old Model and NM Super BHs post c. 1962 and pre c. 1999.
Original large frame Vaqueros pre c. 1999.
Old model Bearcats post 1962.
All "Super" Bearcat old models introduced in 1971.
All new model Bearcats introduced in 1993.
The early stainless new model Bearcats have alloy silver anodized ERHs, only very recently changed to stainless steel ERHs.
*NOTE: There are several distributor exclusive, non-regular production model exceptions to the above such as the Buckeye Blackhawk convertibles that have steel GFs and ERHs, etc.
