Bill let us know what yours measures and I will measure the other 4 and get back to you !:rotf:

Pictures please

Measured per the diagram on p.45 in the Serialization book, the SC that I have measures:
1.70" at the frame
1.69" at the bolster
1.61" at the hinge

According to the chart:

1) The only difference between a 1 frame and a 1 1/2 frame is the measurement between the pins. (Which has no application to an SBT)

2) The only differences between a 2 frame and a 1 1/2 frame is the measurements across the bolsters and of the standing breech. (Neither of which can be used to make a comparison between a Parker SBT and a Parker side by side)

3) That leaves only the measurements across the breech and the hinge. (Which are the same for all three frame sizes, ie 1 3/4 and 1 5/8 respectively.)

And of course, the "1 1/2" frame SC 237938 measures 1 3/4 across the breech and 1 5/8 across the hinge.

So, all that got me nowhere.

SBTs are not assigned a frame size. The 1 1/2 mentioned by one poster is just to fill in a blank column in the stock book. All 12s and 20s are the same size. I have a 20 with an extra barrel in 12 gauge that is off another 12 gauge gun, fits perfectly. My 34" 20 also has an extra 34" 12 gauge barrel that fits just fine.

Thanks Bill, that settles it then.





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Bill, reasonable explanation. However, me thinks you got lucky with your 20/12 SBT. None of my 4 Parker SBT's are interchangeable in any manner. At least not without a lot of filing and fitting.

John, the extra 34" 12 gauge barrel for my 20 gauge 34" SBT is not a perfect fit, but it works and shoots and I will get it properly fitted some day. It needs a thicker bolt plate. The extra barrel for my other 20 is a perfect fit and I shoot it regularly.

Bill, you are a lucky man.

Lucky and broke.