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ww321q
07-10-2014, 05:37
In your book , in the section on the 1866 rifles you say "The hammer nose was slightly angled, as is the rear of the breechblock comb, so that the joint between them did not form a line perpendicular to the bore, as would be expected, see Figure 3-11, arrow. The reason for this unusual feature, observable only from the top, is not known."

It's not known because there is no documentation as to why? I'm sure this was covered in the past but was curious as to why it was put that way. :) thanks for writing the book too! JW

Dick Hosmer
07-10-2014, 09:25
Just an observation I happened to make while poring over the guns, prior to and during writing of the book. I had never seen anything in print about it, nor have I had a revelation since.

It makes no sense that I can see, but, AFAIK, they are all that way. I'm not a machinist, but I would think that any time you can make a cut at 90°, it is simpler than having to set matching angles on different pieces.

ww321q
07-11-2014, 05:16
I can't remember where or on what that I saw and solved the problem. Somewhere in my past. But I knew exactly why it was done. With the firing pin set at an angle the hammer has a tendency to drive the firing pin into the side of the firing pin hole. At best it causes drag and wears the hole more or it could even bind . By angling the hammer head face it would hit on the right side of the firing pin driving it more to the center. I actually had to do that on something I repaired or built to get it to work properly. Wasn't gun stuff something else. :) JW

Dick Hosmer
07-11-2014, 08:27
Well, yes, what you point out is fairly obvious - anything other than a straight blow is going to cause some, even if microscopic, amount of sideways force, friction, whatever. What I find odd - and commented upon in the book - is that only the 1866s have that feature. The 1865 does not, nor does the 1868, nor does any subsequent models until the design was dropped in the 1890s. Just another little 'mystery' about the 1866. A monograph could be written on just that one model.

ww321q
07-11-2014, 09:13
oops double post

ww321q
07-11-2014, 09:23
Different firing pin design maybe? My m66 firing pin is symmetrical and could rotate. Are the other models the same? Do any of the others use a threaded retaining collar? I have only had a m66 in my hands. The others I've only seen in pictures. :) JW

Dick Hosmer
07-11-2014, 11:27
Good catch, and, honestly, one I had not thought of. The 1866 is the only trapdoor with the collar retention system. Every other model uses some sort of screw intercept, and has a slot (of one shape or another) in the pin.

Having said that, however, I can still see no reason why the slanted interface would provide any advantage whatsoever. Thanks for bringing this up - maybe someone else can point out a good reason.

ww321q
07-11-2014, 01:11
I checked and the firing pin and hammer face are at 90deg to each other right to left . Could have to do with the reduced firing pin size where it goes through the retaining collar? Binding, bending or breaking? :) JW