Nitro Special firing pins dragging

[Hebron]

I have a 1924 Nitro Special 12 ga. The gun had not been used for 20+ yrs. After about 100 to 150 rounds the gun began to hang up when trying to break it open after firing. I have cleaned the action well and lubed it. The firing pins appear to move freely. After firing, they extend 0.087” and 0.073” from the breach face. There is 0.010” and 0.016” clearance under the cocking cams

I have not taken any of the receiver apart at this time. Should I look at replacing the cocking cams or cocking rods? Can I replace the cocking rods by pulling out the front when the cams are removed?

 

[troy fairweather]

I'd take it all down and clean it.

 

[Hebron]

I'd take it all down and clean it.

I cleaned the entire action. The cocking rods move freely, are not bent and are of equal length, 2.915”. I cannot find anything that appears to have significant wear. The gun is old but does not appear to have a great deal of service. Next clays day I am going to try some different brand shells from other guys to see if that makes a difference.

 

[mnrivrat]

A good chance your issue can be in the ammo you use. I wouldn't change a thing on the gun until you look at firing different ammo. Make sure of course that your chambers are clean . Try some high base ammo as well to see if that makes a difference. If problems still exist polish the chambers would be my first order of business if doing anything else on the gun. Some of this new low base ammo is terrible when it comes to extraction as it does not come back from the expansion caused by firing pressures.

 

[Clemson]

Chances are very good that your gun has short chambers. The standard length for that time period was 2 5/8 inches for 12 gauge guns. Google up "RST shotshells". They still load 2 1/2 inch shells for the older guns. They are excellent shells.

 

[BBBBill]

Chances are very good that your gun has short chambers. The standard length for that time period was 2 5/8 inches for 12 gauge guns

^^^ Short chambers and very abrupt forcing cones. Verify and either purchase the correct ammo for your particular chamber or verify barrel wall thickness and recut the chambers/forcing cones to modern specs if there's enough material there to do it safely.

 

[mnrivrat]

Certainly there is a need to check chamber length. I am not convinced that is causing the issue he is seeing, but yes, it should be checked, and could be possible. I see it as a pressure issue but have seen a number of break open guns that have a 2 & 3/4 " chamber that were fired with 3" shells and gave no break open or extraction problems. To the OP . please inform us what was found to be the issue after you find the problem.

 

[shooter1niner]

Not knowing anything about the design or function of this shotgun I have to ask, is it normal for the firing pins to protrude from the breech face after firing? Why don't they retract after firing?