Mike 

The earliest "X" suffix M70 I've found to date (not counting the odd R&D gun) is s/n 75829X (1947).

Those "D" prefix M70s perplex me.  Besides the (4) in the clip below, there's s/n D8702 that RatRod Mac recently ran across.  There's nothing at all "special" about these guns, and you can see that there are numbers in-between that lack the prefix.  These are the only "D" serial numbers out of about (24,000) in the survey and they're in a block of (50) or so...

I've wondered if maybe the guy stamping M70 serial numbers on a Friday in 1937 forgot to record the last number he used, causing the next guy on Monday to start in the wrong place and stamp a whole block of duplicates?  I asked Pauline Muerrle to check the original PR logbook for 8690 through 8740, but there's nothing there to indicate duplications (or explain the "D").

Which raises another question... How many M70 receivers were actually made?  We know s/n 1 was stamped on Jan 20, 1936 and the last number used, 581,471, was stamped on Oct 18, 1963.  But "X" serial numbers are not rare, and it doesn't appear that the factory "skipped" the next number to keep the count accurate.  For example, I have s/n 422990X.  If there was a 422989, 422990, 422990X, and 422991, then there's one more M70 receiver out there than there were serial numbers used.  In the M70 survey, it appears to me that the number of "X" serial numbers may be as high as 1 in 500 to 1 in 1000, which would suggest (600) to (1200) more than 581,471 M70 receivers were made.

Hmmmmm...

Lou

That would agree with both Rule's book and what's in the survey.  It happens that my relatively few 1955 or later Super Grades (excepting the Africans, of course) have the Redfield 255.  All my earlier Super Grades have the Redfield 254 except the 24-inch heavy barrel 375 Magnum.  It has the 0.260" tall Redfield full gold, which is the same height as the Lyman 31W gold bead found on (at least most) of the 375 Magnum Standard rifles with that barrel.

It's hard to know what "should" be on a heavy straight taper 375 Magnum Super Grade (they aren't too common), but I've got enough of the Standard rifles recorded to know that they used the lower Lyman 31W front sight with that heavy barrel.

Best,

Lou

Bert

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TXGunNut said
I seem to recall 45 caliber was sometimes expressed as 45/100 as in 45 100ths of an inch. For me in a military rifle of that era that would mean 45-70 or 45 Guvmint. 
 
Mike
  

Mike, I think this is the best explanation. The 100 has nothing to do with the powder charge.  It is the fraction for a 45 cal bullet. 

Csterling1966 said
Or should I say 32 Winchester Special ?
Chris
  

That would be correct.

TXGunNut said

As far as the rifle or carbine is concerned the chambering is probably best described as 45-70 or as I prefer 45 Guvmint. Like you I find the variations of a few of the 45 (and 50) caliber cartridges fascinating and confusing when two or more cartridges share very similar overall dimensions or may be chambered in the same rifle. I believe a similar practice was used with the Trapdoor. The confusion continues when modern weapons in 45-70 (and 45 Colt comes to mind) will safely chamber cartridges capable of pressures and velocities likely not imagined 153 years ago. 

I was disappointed to discover during a recent safe dive a Hotchkiss has yet to follow me home. Perhaps I may need to be more proactive in this area.
 
Mike
  

I recently bought my first Springfields.  One is a beautiful trapdoor rifle from 1878 and the other is a Military 22 training rifle used during WW II.

Chris