Got the Rossi today.  I haven't gotten to shoot it yet (probably tomorrow), but evidently quality control and finish since the last one I looked at has increased exponentially.  It's either that or someone already slicked it up.  I do need to replace the plastic follower and plug the safety, but the rest of it is pretty amazing after what I remember Rossi's being.  Next we'll see how it shoots.

Values for the Springfield Armory Spencer rebarel/conversion like yours are a bit all over the map. Mostly because it doesn't look correct and few people are aware of them. 

I picked one up a few years ago for about $2K. Came with a conversion breech block and the bayonet. Unfortunately the stock is not original. It was a poor attempt at fitting a reproduction stock. I'm still looking for an 1868 trap door stock to fit to the gun. My research shows that this was the stock that Springfield Armory used when they built them.

One oddity you'll notice is that the cleaning rod is actually too short for the barrel. This is because the design of the Spencer receiver doesn't allow the cleaning rod to extend beyond the breech face.

I've now shot 4 matches with the New Model Navy conversions.  I'm not sure if I had any pistol misses the first match, but a rifle squib (using up old ammo) ruined a clean match.  But the last 3 matches have all been clean matches.  A week ago I shot BP in them for the first time.  I just sprayed the barrel gap with moosemilk and spun the cylinder after every stage and they worked fine for the whole match. 

Fortunately empties mostly fall out of the chambers at the unloading table.  But not with BP, had to use the ejector which is a bit fiddly but no problem.  These guns are also noticeably heavier than my '51 R-M's.  Hopefully the new grips will arrive this week.

WOW!

2048cupcakes has been reported. 

I can't find this book on Ebay. Maybe it 's not available on this site. Where can I find it?

Hello:

Just viewed the Ballistic Recreations website, and saw that it is slightly revised to include details about its and substitute annealing salts.

BR's mixture is detailed together with Gary's comments about alternative sources and possible issues with other formulations. Probably wise to visit and print the info if matters. 

Months ago, Gary emailed me mostly the same, but included: Weighing by "mass" refers to scale weight, not volume.

The chemical designations for "sodium nitrate" are TWOFOLD. 
So: 50% Potassium nitrate KNO3, 45% Sodium nitrate NaNO2, and 5% Sodium nitrate NaNo3.  NOTE: 2 vs 3.

Smiles.
El Supremo/Kevin Tinny

One of the other, issues ASM was having is fending off COLT.

The ensuing lawsuit was over the last parts unshipped for 3rd Gen BP Colts.
ASM marketed their Walkers with the Address SamL COLT Hartford Conn.
roll engraved barrels.
I had one, I bought NIB from Tennessee Shooters Supply.
COLT screamed bloody murder, and filed suit...
T'was just another nail in ASM's coffin 

  Hiya Sir Barr 

Actually, for a 429 Bore, proper Bullet/Throat diameter for lead bullets would be .430, just to use a round number.  The benefit of corrected throats is somewhat less felt recoil and a bit better accuracy.  HOWEVER:  For SASS/CAS/NCOWS target distance and load, I'd have to agree, reaming all those throats would be somewhat of a GROAN!!  Although, in my storied past, when I had my Shingle out I did spend considerable time fixing handgun throats that were far enough "off" to be problematic.

  Holy Guacamole Compadre

How very interesting!!  Like you, I knew American Freedom Arms made a real nice Open Top which I lusted after.  However AFF went bust before I could put the shekels together to snag a pair of them.  It makes sense though, If AFF was able to source Open Top parts, ASM could certainly have made their own.  HOWEVER:

In actual answer to your question > > > > NO!!  In the decades I was building toggle Link rifles and served as an Open Top Mechanic, I never saw an ASM Open Top in the wild.  I chalked them up to Rumor and Propaganda.  I still haven't seen a sample example.  Could be, ASM was so embroiled in the quality control fiasco with the "Richards" guns they never got the Open Top into production.