Corrections to previous post: Sukalle's shop was at 1120 East Washington, Phx, AZ.
Added Information: I posted to another forum an inquiry and got, so far, one informative response. Sukalle had a shop in Tucson before relocating to Phoenix, years unknown. His barrel will tell which shop produced the rifle as it will be marked either Tucson or Phoenix.
Serial numbers were usually four or five digits. The last two digits are believed to be the year of manufacture.
Further References: American Rifleman, June 1950, "Bill The Barrelman" article and photo on cover. I have yet to locate this copy. Precision Shooting, October, 1999, "Custom Sporting Rifle Makers".
AND other misc info: Jack O'Connor refers often to Sukalle as his barrel maker of choice. Sukalle made 10 barrels for Jack's 270s and Linden did the stockwork. The bulk volume of his gunsmithing seems to have occured in the 30s.
One customer today bid on Sukalle's equipment when he retired but everything went to an unnamed gunsmith in Buckeye, AZ. Another regular customer is a retired gunsmith from the Phoenix area and may have added information. If so, I'll post any of his pertinent recollections and see if I can find the Buckeye gunsmith.
Sukalle may have moved to Prescott upon retiring.
IMO, a Sukalle rifle is an undervalued collectable. Even if subsequent modifications have occured, having the Sukalle trademark on the barrel has value and further modifications should be considered in this light.
I want to find the referenced articles and see what else can be gleened about this remarkable barrelmaker. Perhaps some list members have access to these magazines and can summarize content.