Thanks gents.
Rst shells in transit. My concern is 2-5/8" chamber and 2-7/8" shells.
Also there is no forcing cones between end of chamber and barrel bores.
More like a step from .850 to .775 diameters. I have not personally seen
The absence of some taper (forcing cone) between the two.
K

From the sound of your description, your gun was made way back in the day for 2 5/8 inch brass shells. All the RST 10-gauge shells I see on their web page are 2 7/8 inch. If you like to tinker, you could cut down plastic Federal or Remington hulls to 2 5/8 inch and modify a loader to handle those short cases.

A far better solution, for lazy folks like myself, is to get a pair of 10- to 12-gauge Gauge Mates and shoot light 12-gauge reloads. My 12-gauge reloads in Remington STS hulls work great in the Gauge Mates.

It still has a forcing cone. It is just a lot shorter for use with brass shells.

I agree 10-12 gauge chamber mates and light loads long term.
Does the 2-7/8 rst shell in the 2-5/8 chamber scare any knowledgeable
10 gauge folks? Chamber mates are on back order until Jan 1.
Rst shell will be here tomorrow. I also have 10-20 gauge chamber mates in transit. Just wanna shoot the old girl (safely) while it's nice outside. And before it gets shipped to Brad b. For stock repair and barrel browning. She'll likely be gone for awhile and we barely met.
K

1875 gun.

Personally, I would shoot it, but that might be a bad idea

Kirby,
I also have an 1875 10 ga. lifter with the abrupt shoulder at the forcing cone and a 2 5/8 inch chamber. When I first started shooting it I was a little concerned about a 2 7/8 in. case opening up into the barrel, but then I measured the bore and found that, like most Parker's of that vintage, the barrels were over bored to .805 inches. Unless you start reloading, which by the way is a lot of fun, I agree with our fellow members about using RST shells. Your gun, like mine, should have a 90 degree angle where the water table meets the standing breech instead of the radius like the later hammerguns. It is for that reason, and assuming your barrel walls are not to thin, that you might like to keep your loads on the light side if you do start reloading.
Have fun, shoot often, and you will learn to love the 10 gauge.

Thanks Austin.
You are correct on chamber to bore geometry and sharp corner @ water table/standing breech. I'll double/triple check wall and chamber thickness but shes sound and plenty thick. I'm ready when shells or chamber mates arrive.
-K

Austin,

So you are shooting 2 7/8" shells in the 2 5/8" chambers? I asked the question before and no one would say to do it. Yet most everyone had no problem shooting 2 3/4" in 12 gauge with shorter chambers or even in 20 where pressures are even higher.

The 10, due to a larger surface area I would think would handle the low pressure loads with thin modern plastic even better than a 12 or 20. I just hate loading 2 5/8" for my 1878 lifter and then 2 7/8" for my top lever. Too much inventory.

I have a 10 gauge Parker in the 13,xxx range. Oops, looks like I shot the wrong kind of shells in it.

The wood is probably a greater concern than the barrels on those early Parkers