Over under Breaking Primers

[R.K.]

I recently picked up a 16ga Sears Ranger (pre-war) to match one my dad has.

But now that I’ve taken it out a couple times, it seems the bottom barrel is striking primers too hard and cracking them- evidenced by a small ring of soot on the primer and receiver.

Before I get too involved in scouring the internet for a fix, does anyone have a suggestion on where to start? Is it a firing pin position issue, a spring that’s too strong, possibly a worn piece in the receiver?

 

[Robert N]

Lacking more info…I’d say a very heavy cleaning, down to the component level first. Then try again.

 

[MThuntr]

Is it a 2-1/2" chamber?

I don't know much about shotgun pressure signs but sounds like those are too hot for a vintage gun

 

[R.K.]

Is it a 2-1/2" chamber?

I don't know much about shotgun pressure signs but sounds like those are too hot for a vintage gun

Only the bottom barrel, and the shells shoot fine in the copy my dad owns.

Lacking more info…I’d say a very heavy cleaning, down to the component level first. Then try again.

Sounds like a fun winter project.

 

[p_ham]

Check the model number, I think those shotguns are Marlin Model 90s.

Firing pin protrusion is the first thing to check. Pull the barrels. Put a piece of delrin, plastic cutting board, or hardwood over the breech face and release the trigger. Don't dry fire without something to absorb some energy.

If this was an issue for any length of time, the firing pin tip is probably damaged.