Main SPring Housing (MSH)
History of the 1911 - Main SPring Housing (MSH)
The original 1911 had a flat MSH with a longer trigger,
than the 1911A1, which came along in 1925. The A1 changes
included: Shorter trigger,, Arched MSH as well as
scallop cuts on the frame just behind the trigger. It made
the 1911 more user friendly for smaller hands.
The MSH consistes of the Housing,for the main spring
which is a coil spring,, a main spring cup, that the coil spring
sits in as well as a tube inside the MSH. The other parts
would be the pins which fit the MSH to the frame. I bought a
S &W 1911 with an Arched & Checkered MSH with a
blued/black appearance - I think it is polymer. I asked about
options on a forum, probably the 1911forum. Brownell's
offfers at least 10 different types and styles of MSH for
1911s. I wanted one in a material like the frame, stainless
steel (SS) as well as flat. I looked at the options. I
selected a Les Baer Custom, Flat SS w/verrtical serrations.
It was about $40. It was fitted by a gunsmith. I mentioned
that I had read that Brownell's sells a polishing tool for
the inside surfaces that may contact the main spring. He
was aware of the elements of fitting in a new MSH. It was
polished, ALso, replaced the main srping Cup with a
titanium replacement part. The original parts are in the
S&W Blue box. I'm very happy with the appearance and
feel of the new MSH. THe serrations aren't rough but give
purchase for the heel of hte palm, as well as having the
same theme as the front strap of the grip also has vert.
serrations. Some other MSH options include those
with the lanyard loop at the rear base. It was a
requirement of the US Army for mounted troops.
Hope this helps your understanding of some of the
1911 internals.
