troubles with a 1865 spencer

[cowolf]

I have an 1865 src converted to a rifle by Springfield. I am installing a centerfire block- follower am having problems.

1) I am having a time figuring out brass. 
2) 50-70 shortened brass won't chamber due to the rim dia being to large.
3) And starline brass will chamber all the way with a little extra room around the case head but won't eject because extractor skips by.
          -No room for thicker extractor. My extractor is thicker than a hack saw blade .0045 to .0028
          - Narrower rim dia lets brass go to one side of receiver half way out of chamber then extractor skips by.
4) turned down 50-70 brass till it chambered and it was  .002 bigger than starline 56-50
5) the rimfire fireing pin has mushroomed the chamber in some but a punch and rattail file have fixed that some.
6) I would like to pull barrel to fix chamber mushroom  with lathe and turn rim diameter so 50-70 brass head fit.
       - thaughts ( I know it's rare but It needs to shoot)
        - I have a highly capable machines to do work
         - I am only cutting .0628 to .0650 on the rim diameter
         - that should let me use bulk starline 50-70 brass shortened. End all the ejection problems.
           -Bore is .509-.510 so a .512 sizer should work figure out bullet mould then figure out trim length for crimp grove then make 300 rounds
7) how the hell dose that barrel unthread. It's soaking in Kroil for a few days befor I try to hard

[El Supremo]

Hello:

I know one thing:
The original barrel shank and the forward end of the outer magazine tube threads are square, not "v" profile.

KROIL should work.  Might take some time.  

Any photo's, please?

Regards,
El Supremo/Kevin Tinny

[Trailrider]

IIRC, those .56-50 conversions were made from .56-56 Spencer carbines. Using Dixie Gun Works and Buffalo .50-70 brass from at least 30 years ago, I had to turn the rims to .643-.645" dia. This worked fine in an original M1860 Spencer carbine (.56-56), with positive extraction by the blade-type extractor.

[Kent Shootwell]

Will that larger rim feed through the magazine?

[DJ]

Only .002 difference between Starline 56-50 and max diameter for your rim seat doesn't sound right.  Is it possible that your rim seat is out of round due to the peening of the chamber from the firing pin?  If so, it could be preventing a "normal" size rim from seating, because you are having to turn the .50-70 rim down to the minor diameter of the eccentric rim seat.

That said, I have not been able to make the Starline brass work reliably with the 1860 extractor.  Part of the issue is the undersized rim, and part of it is the undersized head.  In my experience, the undersized head allows the case to tip slightly to the right on extraction such that the right edge of the rim is against the right receiver wall, and the resulting gap on the left is big enough for the extractor to slip past--"sometimes."  Prudent expansion of the case as far down toward the head as possible might improve reliability, but I haven't gone this route yet.  The Starline brass works better with the Lane-type extractor, but I haven't wrung the bugs out of it yet.

Anyway, I would check to see if the rim seat is out of round and fix that before I enlarged it beyond original spec.

--DJ

[Pitspitr]

COY!

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