Need info regarding bbl fitting

[Don Strelioff]

Would it be possible to fit bbl’s stamped no 1 onto a 1 1/2 size action

[Brian Dudley]

There is no interchangeability between frame sizes.

[Don Strelioff]

There is no interchangeability between frame sizes.
Thanks for the info . So much for that plan

[Bill Murphy]

#1 and #1/2 frame barrels can be interchanged, in my experience.

[Dean Romig]

Page 45 of the Serailization book tells us that the only difference between the 1-frame dimensions and the 1 1/2-frame is the firing pin separation being 1/16” different... meaning the pin strike might be 1/32” off center... which is probably negligible.

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[Brian Dudley]

Page 45 of the Serailization book tells us that the only difference between the 1-frame dimensions and the 1 1/2-frame is the firing pin separation being 1/16” different... meaning the pin strike might be 1/32” off center... which is probably negligible.

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I recall seeing one of those ridiculous gunsmithing competition shows where one group cobbed together a Parker hammer gun using different frame sizes for the barrels and frame. In firing the gun, they dealt with light strikes and misfires about 50% of the time. Not quite negligible.

[Dean Romig]

Apples and oranges. Too many variables there. We know the difference to be exactly 1/16”/2=1/32” so I’m more inclined to believe it very well could be negligible.

The only to know for sure is to try it.





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[Brian Dudley]

I cannot believe what you are suggesting...

[Dean Romig]

I cannot believe what you are suggesting...


If it were dangerous I certainly wouldn't suggest it. The only thing it might be "dangerous" to would be somebody's wallet. :cheers:





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[John Dallas]

I embarrassed myself years ago by snapping a set of M21 20 gauge barrels on a 12 gauge M21 frame. The hammer strike was off center enough that the gun didn't fire. One grouse was very happy/lucky

[Dean Romig]

Good Point John. The difference between 20 gauge and 12 gauge firing pin centers is waaay more than 1/32".

I wonder what the firing pin spacing is on a WIN-21 12-gauge frame and what it is on a WIN-21 20-gauge frame... what the difference is?



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[John Dallas]

Dean. Am at my cabin. Will be home tomorrow and will measure. I don't remember seeing those measurements in Schwing's M21 book.

[edgarspencer]

A 1/32" may not seem like much when looking at the primer head, but the primer's anvil is quite pointed, and I think you're asking for misfires.

[Dean Romig]

If the pin were as pointed as the anvil I would agree, but the ‘firing pin’ is rounded.





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[edgarspencer]

Pointed or rounded, if it doesn’t strike the top of the anvil, you’ll risk a misfire.

[Dean Romig]

I get that Edgar. What I'm doing is playing the devil's advocate here in this case.
If I had a 1-frame hammerless and an orphan set of 1 1/2-frame barrels I would attempt it myself. Like I said previously, there is no danger in doing it and I would really like to know.
Incidentally, I do have a 1-frame GH 12 so if anyone has a loose set of 1 1/2-frame barrels I would entertain procuring them for the stated purpose.





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[James L. Martin]

Dean I just measured my 12ga & 20ga model 21 .12 was 1.145 and 20 was 1.020 for a difference of .125 or 1/8 inch.

[Dean Romig]

Now that’s a lot.

No wonder it didn’t fire. :cool:





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[John Dallas]

My ham-fisted measurements Showed 1" 4/32 for the 12, and 1" 1/32 for the 20.

[Craig Budgeon]

I'm with Brian and Edgar, the only time when 1/32" is negligible is when your cutting a 2 by 4 for an outhouse.

[edgarspencer]

I'm with Brian and Edgar, the only time when 1/32" is negligible is when your cutting a 2 by 4 for an outhouse.

That will go into my book of favorite quotes.

[Dean Romig]

I'm with Brian and Edgar, the only time when 1/32" is negligible is when your cutting a 2 by 4 for an outhouse.


:biglaugh:





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