Thanks for that info, ASM!
A few more worries on my part...
If you recall, this is the frame I tried to repair several years ago by removing the roll pin staking the arbor in, rilling and tapping the roll pin for a 4-40 screw, and reinstalling the loose arbor using Loctite and the screw in place of the roll pin. It worked well...for about a dozen shots.
Then the slide hammer effect got down to business and worked it loose again...my bad, because I did nothing to repair the excessive cylinder gap as a result to the inner ring being battered.
So, now this old frame has become my guinea pig to experiment on.
First step is to remove the set screw......and unscrew the arbor.A quick view reveals the threaded hole is somewhat elongated (egg-shaped) and dangerously close to the hand slot. This is what is throwing the stick in my spokes, as my intended repair involved drilling this threaded hole oversize and installing a Helicoil insert. Now Im not sure if there is enough material to accomplish the task...
A closer view:I may forge ahead and try it. Worst that can happen is I'll trash an already junk frame. But I will have to invest $30.00-$40.00 in a Helicoil insert kit for 8X1.25 metric inserts, and if it's not going to work, that's wasted money. I believe I will look at my other brassers to see if they have more material on the frame than this particular Pietta frame does. If not, I may revert to my Plan B, which involved cross-drilling though both frame and arbor and securing with another set screw.
BTW, I was able to find a source for a new steel frame (Taylor's):
http://www.taylorsfirearms.com/pietta-1851-navy-parts.htmlItem number 14 as follows:
1 x #14 - A340.A44 Navy Frame Steel Finished .44 (Includes Parts #13,14,37,41) +$177.00...but at $177.00 + shipping, you could pretty much buy a nice steel framed revolver if you add in the cost of your 100 dollar brasser.
If you already HAVE the brasser, that may not be a bad option at less than the cost of a new steel Navy.
But not wanting to get off track here; the original goal was to be able to develop a mod to easy and reliable shooting of a brasser with normal loads.