Encore 45/410 Primer Problem

[Roger_Dailey]

I'm getting some pieced primers when shooting 410's in my 15" 45/410 VR barrel.  I've only tried one brand of ammo and plan to try others.  The firing pin protrusion is about .040".  I've not had any problems with the 44 mag barrel, 209 muzzleloader barrel or heavy 45 Colt loads in the 45/410 barrel.  I suspect the ammo (Fiochi) is not compatable, but the same ammo works fine in an Topper.

Thoughts, hints appreciated...
Thanks,

[Kywoodwrkr]

Roger,
Not trying to hi-jack your string but how is your 45 barrel marked.
I recently bought what I had assumed was just a 45 LC barrel(10") and it looks like it is chambered for shotshells.
Is yours marked as being for 410 as well or
Pierced primers might be from the TC firing pin being smaller than a shotgun firing pin.
I am not an expert by any stretch on shotguns however.
I'm going to try some shot shells in mine so will see how primers are marked afterward.
But I'm sure you will get more and better feedback before I get that done.
DaveP   kywoodwrkr

[Roger_Dailey]

Roger,
....
Is yours marked as being for 410 as well or
Pierced primers might be from the TC firing pin being smaller than a shotgun firing pin.
....DaveP   kywoodwrkr

Dave,
Thanks for taking time to discuss my problem.  The barrel is marked "45 Colt - 410." and has the removable internal choke.  I looked at some of the ruptured primers and they appear to have ruptured from the pressure of the round being fired.  That is, the center of the primer indent is pushed back out towards the firing pin.  The leak is from pin point sized holes in the center of the indent which is extended towards the firing pin.  One thing I've observed is that if I cock the hammer and then let the hammer down slowly while keeping the trigger pulled, the comes to rest about 3/16" away from the frame.    I don't know if that is typical? 
Anyway, thanks again for taking time to help,
Merry Christmas from Roger D. in Southern Indiana