10 gauge bore size

[Eldon Goddard]

What is the common bore size for early 10s. Is .800 not uncommon it seems rather large to me. Technically that is a 9 gauge I believe. I know early parkers had oversize bores but I have not read what the bore size was for 10s only 12s.

[Bill Murphy]

You are right. .800 would not be unheard of. Of course, most bore micrometers won't measure that big.

[Jerry Harlow]

My 1883 10 is larger than .790 in both bores; this is as big as my gauge will measure. The barrels are over .050 thick and I do not believe they have ever been touched.

My 1892 & 1897 10s are right on standard 10 gauge specs.

[scott kittredge]

all mine ran .783 to .805 most .780's to low .790's.

[Richard B. Hoover]

You are correct. Above 0.800" is out of the 10/2 bore diameter range.

Five questions:

1. Where in the barrels are you measuring the bore diameter? It should be measured 9" or 15" from the breech. if you are too close to the breech you may still be in the forcing cone.

2. Are the barrels pitted. Putting in the bores could take a 10/2 bore into the 9-ga range.

3. Are the barrels shiny--if so, they could have been reamed out.

4. Do the bores have full length tapers. Parker did this on very early barrels, but is only know of a few and they all seem to have been made in the 1873-1876 time period.

5. Will a modern 10-ga shell fit in the chambers?


I have a bore gauge that goes above 0.850". If you will have your gun at the Southern, I would love to measure your bores and chambers.


Richard B. Hoover

[Eldon Goddard]

Thanks guys alot of good information. This is a DH I am looking at made in 1890. The description says there is light pitting in the bore. Richard to answer your quetions:
1. I believe he is measuring correctly as he measured the 12 gauge barrels with a bore diameter of .734( the gun was sent back to have a set of 12 gauge barrels fit post 1912) which seems correct to me.
2. The barrels are described as lightly pitted.
3. No
4. I would assume no.
5. I would assume yes.
And to the last question will I be at the Southern? I wish.
Eldon

[Bill Murphy]

Richard, what bore gauge do you use?

[Richard B. Hoover]

Richard, what bore gauge do you use?

Bill,

I use precision Browne & Sharpe bore gauges that are accurate to o.ooo1". I have one that is on extension rods and can go 15" into the barrel and covers a range from approx 0.650" to over0.800" (these numbers are from memoryasI am at a dog show in Birmingham."

I have a set of smaller gauges as well as a larger gauge (5" depth range) that will handle all chambers I have encountered--- think it would even cover the Real Mans gun -the mighty 8-ga. Parker.

Richard

[Richard B. Hoover]

Thanks guys alot of good information. This is a DH I am looking at made in 1890. The description says there is light pitting in the bore. Richard to answer your quetions:
1. I believe he is measuring correctly as he measured the 12 gauge barrels with a bore diameter of .734( the gun was sent back to have a set of 12 gauge barrels fit post 1912) which seems correct to me.
2. The barrels are described as lightly pitted.
3. No
4. I would assume no.
5. I would assume yes.
And to the last question will I be at the Southern? I wish.
Eldon

Eldon,

The 10-ga bore size only goes up to 0.793".anything above 0800" is either a 9-gauge or an 8-gauge. What are the chambers like? Will they chamber a modern 10-ga shell or is it sloppy? I do not think Parker ever made a 9-gauge gun.

Which means you may have a 10-gauge that was bored out some time in the past- (not very interesting) -or you may have an 8-gauge (very exciting).:corn:

So to help resolve your mystery,I have three other questions:

What is the Serial Number?

What is the length and weight of the barrels and the gun?

What is the Frame Size?

There are some guys on the forum that know a great deal about 8-ga guns.

GoodLuck!

Richard

[Eldon Goddard]

Richard
It is a 3 frame, serial number in the 58000 range wont give exact number as it is not mine just looking at it to buy. 32'' barrels and I believe it is a 10 gauge just sounds like it has oversize bores.

[Forrest Grilley]

The two 10 gauges I have, one top lever made with 50,000 SN range, and an underlifter made with 25,000 SN range, have identical .793 bores. Like many of the early 12 gauge guns that have bores around .750, many of the early 10 gauge guns have bores in the .790-.800 range. I think it was Austin Hogan (if I'm wrong on that credit I apologize, for some reason I remember him discussing this topic) that plotted out a 12 gauge chart showing when the big change that took place in tooling for 12 gauge boring, and after that change 12 gauge guns were bored to the modern .729 constantly. I would guess 10 gauge guns followed that same path, but more research would be needed. I think it was concluded that measuring the chambers was the only reliable way of determining the true "gauge" of the gun.