Last weekend my Cimmaron ‘73 had a string of about 5 failure to fires. It was the last stage of the day on day 1 of a 2 day match. I bought this carbine new in 2003 and never had a problem with it. I did take the firing pin out last winter and clean the firing pin track. After the string of malfunctions I took it home and took it apart. Nothing apparent was observed. The firing pin, firing pin spring, and firing pin track did not show any sign of excessive fouling.
I’ve run this carbine all summer without cleaning the firing track with no problems before. This match was the 2nd 2 day match in 2 weekends. The carbine had approximately 100 rounds through it the previous weekend with no problem. On the day it failed to fire it had been running fine for 5 stages of 10 rounds each.
The failure to fires occurred after about 4 shots, then the 5 failure to fires, then the carbine fired the 10th round.
There is no sign of a light primer strike on the ejected cartridges.
The rifle is calibrated to .44 Special, I was using Starline brass, CCI primers, Trail Boss and my cast RCBS 44-200-CM boolit cast with scrap lead lubed with Alox. This combination has proved successful for me for years.
I’ve ordered a new firing pin spring. Brownells did not have a new firing pin in stock. I’ll keep you posted how the test firing goes when the new firing pin spring arrives. But you know how these things go, what works at a leisurely practice session is not guaranteed to work at a match.
Just to be sure I went out and bought a brand new Winchester (Miroku) ‘73 with a 24 inch octagon barrel in .44-40 for the 2nd day of the match. I’m really happy with the Winchester/Miroku.