the higher grade Darne French shotguns have this feature.

J. D. Dougall had a patent on his "Lockfast" action. (Patented in the mid 1860's - originally for a pinfire cartridge) On the standing breech face, there were two raised bosses/roundels that fit into a recess in the breech of each barrel. The gun had a lever along the right side of the receiver that, when turned down, moved the barrels forward approx. 1/8" and then allowed them to swing down.

Many others did something similar (perhaps upon expiration of earlier patents). Collath drillings have the same basic mechanism as Dougall's, but it uses a very large lever underneath the forearm/foreend to actuate it.

Maybe it's just from one hundred and thirty five years of shell bases popping against it. :rotf: :rotf: :rotf:

I am no expert but maby it has something to do with makeing a better gas seal.

I really enjoy the things we can learn on this forum. Not only the newby's but the experts too. Thomas

Rebated guns
 

Here is ser#11856 It is a grade 5 lifter, Photos are not very good took them at night, Gary

I have seen this feature on the Darne guns before, but in those the barrels slide forward to clear the shell from the standing breech.

Gary, upon opening the gun you pictured after firing a shell, does the cartridge base drag against the recess such that the gun is hard to open?

Was this recess in the standing breech only in some lifter actioned Parkers. or did some top action hammer Parkers also have it? I've never seen it in any hammerless Parker and assume no one else has either? Did some T-latch Parkers have it? The ones I have seen did not.

I think a "better gas seal" was desirable at the front of the chamber in the area of the cone but not at the breech area. Here is a picture of a Grade-6 T/A Parker Bros. hammer gun I photographed extensively for an article I have been working on. It is obvious that relieving the gas pressure at the breech faces was the desired result of this machining.



.

I have shot mine several times with modern shells. I do not have any brass shells.

I have never noticed any deformity, dragging, hard to open, etc.
The guns functions great.

I did not have to do anything to the head space to make modern (RST) shells fit. They went right in.

I am not really sure what function this feature provides.

Dean I have seen that done in the event of a peirced primer usually on rifles. That is the first shotgun I have seen with this feature. I believe that what we are seeing with these rebated guns was an attempt at what was precived to be a better idea. Perhaps they decided it wasn't needed any longer.