Original Spencer "chipped chamber"--problem or just unsightly? **Photos added**

[DJ]

In looking at lots of original Spencers over the years, I have noticed that a large number of them have a portion of the left chamber wall missing where the chamber wall is thinned for the blade extractor slot.  The missing portion is a few thousands of an inch thick, about 3/16ths of an inch long, and all the ones I have seen were roughly triangular.  By my rough estimate, about half to two-thirds of the Spencers seem to have this defect. 

I would guess that because the missing metal is so thin, and the cartridge cases are so thick at this point (at least for those using modern cases), it shouldn't be a problem, because the missing metal is pretty minimal.  Also, the extractor supports the cartridge case at that point.  However, if you were shooting a Spencer that did not have an extractor in place, I could imagine some problems that could crop up--shortened case life, stuck cases, or even case failures.

Has anyone else noticed this?  How common is it?  And more importantly, has it ever presented a problem for anyone?

#1692—M1860 Rifle with intact chamber


M1860 Rifle--closeup of thin chamber wall over extractor slot


1707—M1860 Rifle with chipped chamber, showing extractor


M1860 Rifle--closeup of chipped out section between chamber and extractor slot.


DJ

[Fox Creek Kid]

My guess is it's caused by thin metal AND exacerbated by the corrosive fulminate of mercury used for priming then. 

[Harve Curry]

 

[geo]

have a model '65 carbine. that side of the chamber by the extractor is very thin but showing no erosion as yours has shown. i wonder about earlier care or lack of. methinks i'd wait for other inputs. my feeling is that you would need to look at your cases to see if there is some kind of unusual bulge or blow-out. mebbe put it on the wall. sorry. the originals have soft metals and could be marginal for safety.  good luck. geo.

[Trailrider]

Howdy, Pards,
If you look at the geometry of the chamber and the extractor slot, you will see that if the chamber was cut a bit too large, the triangular penetration will result.  With the thin, flexible rimfire cartridge cases, the case wouldn't have enough strength to prevent any thin section of metal from bulging into the extractor slot.  With MODERN, BRASS, SOLID-HEAD brass you should have no particuler problem as long as the pressures are kept to black powder levels, either with BP, or a BP substitute.  BUT, I CANNOT CONDONE OR BE RESPONSIBLE FOR SHOOTING ANY FIREARM THAT IS 145 YEARS OLD!  (Do not ask me what I have done in the past... please!  And the piece in question is still in the same condition in which I bought it some 35 years ago!  )

I haven't got there yet, but I am strongly thinking of a Taylor's .56-50 rifle or carbine.  As a "Capt. of Cavalry, detailed Bvt Major of Ordnance", I can't make up my mind.  With the availability of replicas, there's really NO reason to shoot an original!

[major]

Trailrider
If you want a Spencer for shooting blanks then you might want to consider one in 44-40.  I have one in 44-40 and I make blanks for it from old 410 hulls.  This makes blanks that will cycle & chamber in the gun.  The blanks are also very cheap and it is unnecessary to stop and pick them up.  For reenacting they are great and the 44-40 is a little less expensive to shoot live too.  For info on blanks you can go to this web site.
http://www.9thnycavalry.webeditor.com/spencer_article.html
Terry

[Trailrider]

Major,
Much obliged for the information.  I'd probably use the Spencer for CAS matches.  Since I already shoot .44-40 pistols, the .44-40 Spencer would simplify the logistics, even if the authenticity wouldn't be there.

When I was actively shooting an original Spencer (before I got into CAS)...a M1860 in .56-56...using rim-trimmed, shortened .50-70 brass with hollowbased bullets (.535-.538" dia.), I worked up some "demonstration loads".  These were NOT "blanks" in the ordinary sense, as they had a bullet.  The bullet was a BALSAWOOD model rocket nose cone, which had a heel at the base, making it easy to insert into the case.  The case was filled with black powder and a standard primer.

WARNING! NEVER EVER POINT THE RIFLE AT A PERSON OR HIGH VALUE OBJECT!!!  But I ran tests with a piece of corrigated cardboard SIX INCHES FROM THE MUZZLE!  Believe it or not, the worst penetration of the cardboard was on the front surface only, and with the particles of powder and partially-burned balsawood!  I used such loads to demonstrate the Spencer at a local museum, which had an outdoor frontier town.  A heavy blanket was used as a backstop, and the loads were carefully checked to insure NO lead bulleted loads got in by mistake!

Nowadays, the model rocket manufacturers make those nosecones out of plastic, and that DOESN'T WORK!    The neat thing about those balsawood rounds was they were the correct diameter without messing with them, and the rounds would feed from the magazine without a bobble!  Ah, well...

[Bead Swinger]

Hi All
DJ - Great photos! Thanks!

You might call me sacraligious for suggesting this  , but I suspect that the primary reason for the 'chip' is based on a mfg. variation. Notice in the photo for the #1707 (great rifles, BTW), and you'll notice how square the 'chip' is.  Again, these slots were created by maching process that was somewhat imperfect; a few thousandths off, and 'chip'.  The irregularity in the chip is probably due to corrosion, etc.

IMHO, with modern brass, and reasonable BP loads, this is probably just as safe as it was 100 years ago. But it's not my gun, either.

The idea for the balsa blanks is royally brilliant. A machinist and a block of balsa could crank zillions of those out. Thanks for the photos; and great shooting!  It'd be great to see those two old girls speaking again.

[minerotago]

I have a Model 1865 with this problem. The chip misisng is ragged and tringular in shape and also with careful examination a hairline crack can be discerned running back a little fromn the chip. When I first saw it I decided that it was simply poor machining and an inherent feature of this particualr firearm.

None the less - Love my Spencer but my wife wont let me take it to bed!