My recent Spencer pics and lots of questions

[N8Gunner]

Hello all, and thank you for adding me to this board !
I stumbled into a Spencer carbine locally ,last week, and I am having the strangest desire to shoot it !
It is an 1860 , with serial # 57494 , which our kind moderator, Two Flints has advised me that it may have been issued to Co. M 1st NY Mounted Rifles , late in the Civil War.
The carbine seems complete, the action functions smooth and as it should.
While the bore is "meh" , I do believe that it has sufficient rifling to spin an appropriate, correct sized bullet.
Just a few years ago, I discovered the joy- the sheer joy, that owning and shooting black powder cartridge brings to me.
I currently successfully load 50-70 for my 1871 Springfield , .577 Snider for my Snider short rifles , and 577/450 for my MkII and MkIV Martini Henrys, as well as .41 Swiss for my 1869 Vetterli and 44/40 for my 100 year old El Tigre model 92.
While I have searched, and read in the *** SORI ***thread here, and elsewhere on the net , I am unclear on a few questions,
so please bear with me while I ask them of those more knowledgeable folks than I , here on this board.

What I need , and am waiting for now, is for the usual suppliers to get the center fire breech blocks , back in stock so that I may buy one.
Which supplier seems to have the better quality breech block of the bunch ?
Would anyone know what the restock lead time has been in the past, so that I can try and figure how long I may have to wait to get a centerfire block ?
How long between batches ?
I have 50-70 brass , in a sufficient quantity , by various makers- Starline, DGW (Dixie), Bell and Jamison
Is there a brand that does better than the others after being cut to appropriate length for 56-56 ?
( as far as rim size etc ?)
I have 50-70 die set x 2, can I expect to be able to crimp the +/- 1" 56-56 case without cutting or modifying the 50-70 seating die ,
or would I have better success trying to source a set of dies for the 56-56 cartridge ?
Would a set of dies made for the 56-50 cartridge , work to load and properly crimp the 56-56 ?
I have a bullet mold coming , that I won on Ebay yesterday. It is a Lyman-Ideal Bullet Mold #533476 .52 Caliber Mini-Ball.
While I may assume that the 533 in the stock number for this mold will cast a nominal .533 bullet diameter,
I am prepared to slug the bore of my carbine and order an appropriate heeled bullet mold from Accurate molds for this carbine,
if the Lyman 533476 does not work out.
Oh, and here is a big dumb question, that with all of my reading recently, I have not been able to figure out.....
Will 56-50 ammunition safely and successfully fire ( and hopefully, perform well ) in a 56-56 gun ?
Hey, Thanks in advance for your consideration and patience on my questions here. I am sure I may come up with many more soon.
I still consider myself a "Newby" , when it comes to BPCR reloading , as I am learning and still learning and will always be open to learning when it comes to the old historical guns, and the making of ammo for them so that we and future generations can enjoy them and touch back to a better less complicated life in our country
Many Thanks, in advance
Nate Bryant aka "N8Gunner" on this and other boards
Port Townsend WA

[El Supremo]

Nice to have you on board, N8GUNNER:

Please allow me to suggest that you speak with Dave Gullo at Buffalo Arms in Montana about the center fire upper block.  He might be able to supply one.
The 50-70 SHARPS brass has a correct, wider rim OD vs. the narrower one found on STARLINE 56-50, which is for the Armisport repro with narrower chamber rim cut OD. The wider OD base extracts better.

Dave can help with the heeled bullet and loading dies for the 56-56.  Other vendors, such as S and S Guns of GLENDALE NY have had CF upper blocks in the past.  The center fire blocks may not be a simple drop-in swap and if so, will require some fitting.  Be sure to have a clear understanding about returning anything that you find off-spec for your Spencer. 
All the best,
El Supremo/ Kevin Tinny

[N8Gunner]

Thank you , El Supremo ! Any and all advice is much appreciated

[Trailrider]

When I was shooting my original M1860 Spencer carbine, I found the Lyman #533476AX (a little different, IIRC, from the mould without the suffix, but not much. Interesting, I shot smokeless powder loads in cases that were cut down DGW .50-70 brass. I cast the bullets using Lyman #2 equivalent alloy, rather than pure lead or 1:20 tin/lead. I got acceptable accuracy at 50 yds. My S&S centralfire breech block required some fitting, carefully using a file on the rear of the block. I would suggest that you slug the bore, but you may find the groove diameter at the breech to be wider than that at the muzzle! Yes, I believe the bore and groove on these were tapered! I may be able to give you more information, when I dig out my data.

[N8Gunner]

Thank You, Trailrider. I gratefully accept and help and information on this project

[mgmradio]

  56-56 ammo can be fired in a 56-50, but 56-50 should not be fired from a 56-56( it will fire, but won't go were you want it to.
  The bullet you want for the 56-56 should be closer to .540". The .539" Buffalo Arms bullet works well.
  You will want 56-56 dies. 50-70 dies will work with 56-50 when cut down, but are to small to properly crimp the 56-56.

[N8Gunner]

Thank You, MGMRadio !

[N8Gunner]

Update.....
I found a nos albeit 2nd hand S&S center fire breech on Gunboards forum last night.
It should be in my hands by Friday.
I think my next steps will be to start cutting and preparing 50-70 brass , and contact ch4d
about a set of 56-56 dies

[Two Flints]

From my SORI Thread.  Maybe, of some help.

https://www.cascity.com/forumhall/index.php?topic=40010.0

[N8Gunner]

Thank you,  two Flints
Great info in that thread, and in the SORI

[Dave Fox]

A center fire Spencer block is offered for sale in the www.n-ssa.org website....

[DJ]

That breechblock assembly on the NS-SA site appears to be built with a Lane-style extractor, which was used with some post-war Spencers.  If the dimensions are right, the upper block might work with an original M1860, but the rest of it would probably take quite a bit of modification.