Questions regarding swivel breech barrels for pistols. Part 2

[Rolf]

We really like Jack Brooks swivel breech pistol  and decided to base our pistol on his. We enlarged a picture of his pistol to 1:1 scale, based on the barrel length and reconstructed the barrel profile. His barrels are swamped, octagonal, 10" long, 3/4" at the breech and caliber 0.45 . We decided to use caliber 0.40 since this is the largest caliber available from GM with a 3/4" breech.





Question1. We want to use swamped barrels and Dave Waters swivel breech mechanism. Daves swivelplates are square, not beveled on the edges. When mounting the lockplate/frisson square on the swivelplate, the lockplate does not lay flat on the swamped barrels. The gap between the barrel and lock is 0.024" at the front end of the lockplate. Will this cause a problem, or could we just put screw in the front of the plates and pull the gap closed?


Question.2Another option is to make the first 2.5" of the barrel at the breech strait octagon and swamp the rest of the barrel. This solution looked strange with a swamped octagon profile, but looks okay with a octagon to round barrel. Which solution would you recommend?


Best regards
ROLFKT

[D. Taylor Sapergia]

I don't think you'll have any trouble pulling the pan-plates in with the cross screw, a total of .048", if you were to mount them flat on their plate... but why not file a little taper into either the plate itself or the pan-plates.  We're not building a watch here.  Nice looking pistol BTW.

[Dave B]

Rolfkt,
It was standard practice to flatten off the section of the barrel where the lock bolster contacts the barrel. That is you are reducing the out flair of the flat that holds the vent liner. I have an original dutch pistol that has a barrel that has this modification. Notice the off set of the panels either side of the tang. The lock side is broader. Now look at the barrel flats the right side of the barrel where the vent is has a flatter angle to the bores center. It is easier to see from the top but I dont have that view in my album.
http://img.photobucket.com/albums/v648/DaveB44/DSCN4602.jpg

[Randall Steffy]

Rolfkt,
The downside of using a screw to pull the front of the forward lockplates together is that your ramrod will necessarily be that much shorter, stopping against the screw. If your ramrod could extent all the way to the front swivel plate, it will be of maximum length and appreciated in everyday use. I remove the taper from the one octagon barrel flat adjacent the lock bolster only, as per Dave B's explanation.
You are taking on a challenging project, and I wish you all the best!

[Rolf]

Thank you for your input. It all helps. It seem like both solutions are viable. I think, I favor the solution where the barrel is strait octangon the last 2.5" at the breech. It seems the easiest to do. The trade off is that you lose some of the sleekness of the pistols profile. Me and Runar will have "chew" on this abit before we decide.

Best regards
Rolfkt

[keweenaw]

Rolfkt,

You don't need to have the barrels straight oct. for the last two inches, only the outside flats and you can fair the top angled flat a tiny bit if necessary.  But, I would file a taper on the pan plate.

Tom