Schmidt-Rubin Rifle in .308 Win.
WAM...@purccvm.bitnet
gun show. This rifle had been sporterized and converted to .308 win. The
dealer said that many of these rifles were converted in the 1950's after
they were imported. According to him the rifle was rechambered to .308 win
by the importer here in the states. This rifle shoots 1" groups at 100
yards and it looks very excellent.
I have some questions:
1. Doses anyone know anymore about these rifles? I know that the
balistics of the 7.5 x55 Swiss are almost identical to the .308
win, but is the bolt mechanism on this rifle strong enough for
modern .308 amo?
2. After I fired the rifle, I examined the spent cases. I measured
them with a micrometer and fount that the shape of the case was
eliptical rather than round. Does this effect the safety of the
rifle? Should I bother to have it fixed by a Gun Smith? Is it
fixable?
I would like any information or opinion that anyone might have
Thanks
Bart Bobbitt
: This rifle shoots 1" groups at 100
: yards and it looks very excellent.
What other size groups does it shoot?
: 1. Doses anyone know anymore about these rifles? I know that the
: balistics of the 7.5 x55 Swiss are almost identical to the .308
: win, but is the bolt mechanism on this rifle strong enough for
: modern .308 amo?
I would think you'ld get the answer to this question before getting
the rifle.
: 2. After I fired the rifle, I examined the spent cases. I measured
: them with a micrometer and fount that the shape of the case was
: eliptical rather than round. Does this effect the safety of the
: rifle?
No, this is very normal. All chambers are elliptcal to some degree. And
cases don't have the same wall thickness around them either. So, ending
up with an elliptical case is par for the course.
If the chamber is larger in diameter than what's `normal' for the .308,
this situation may be aggrevated somewhat.
How did you determine the case was elliptical? The standard machine shop
tool to determine this out-of-round condition is a roundness gage.
Micrometers typically don't do a good job of determining roundness.
BB
K. Karcich
# I purchased a M1911 Schmidt-Rubin rifle about 4 months ago at a local
#gun show. This rifle had been sporterized and converted to .308 win. The
#dealer said that many of these rifles were converted in the 1950's after
#they were imported. According to him the rifle was rechambered to .308 win
#by the importer here in the states. This rifle shoots 1" groups at 100
#yards and it looks very excellent.
# I have some questions:
# 1. Doses anyone know anymore about these rifles? I know that the
# balistics of the 7.5 x55 Swiss are almost identical to the .308
# win, but is the bolt mechanism on this rifle strong enough for
# modern .308 amo?
I don't have much specific experience with this action, but I have see
information in the American Riflemen regarding Schmidt-Rubins which
blew up after being converted to .308. I don't remember if the problem
was the action or the mechanics of the conversion.
# 2. After I fired the rifle, I examined the spent cases. I measured
# them with a micrometer and fount that the shape of the case was
# eliptical rather than round. Does this effect the safety of the
# rifle? Should I bother to have it fixed by a Gun Smith? Is it
# fixable?
Share your measurements. How eliptical. If the chamber is not round, and you
want it fixed, you are going to have to rebarrel the gun. If its not very
eliptical, it might not be much of a practical problem. Many chambers are
somewhat out of round or non concentric with the bore, but there are limits.
If it were me, I would probably pass on this gun.
regards, Ken Karcich
#
# I would like any information or opinion that anyone might have
# Thanks
Tom R Dennis
#In <940228163...@mentor.cc.purdue.edu> WAM...@PURCCVM.BITNET writes:
## I purchased a M1911 Schmidt-Rubin rifle about 4 months ago at a local
##gun show. This rifle had been sporterized and converted to .308 win. The
##dealer said that many of these rifles were converted in the 1950's after
##they were imported. According to him the rifle was rechambered to .308 win
##by the importer here in the states. This rifle shoots 1" groups at 100
##yards and it looks very excellent.
## I have some questions:
## 1. Doses anyone know anymore about these rifles? I know that the
## balistics of the 7.5 x55 Swiss are almost identical to the .308
## win, but is the bolt mechanism on this rifle strong enough for
## modern .308 amo?
After I bought my m1911 in 7.5 swiss, I began doing some research into the
rifle and found out some interesting things.
NEVER load a hot round in the m1911. The reason is that the bolt face does
not fully cover and support the back of the round, thus if the case were to
rupture, one will get nasty bits in the face. Follow suggestions for the 7.5
Swiss rounds as to loads. My source was the Hornady reloading manual 2nd ed.
When I shot my rifle using ammo I purchased at a gun show, I noticed some blow
back around the neck of the case. I'm not sure if the ammo was old or just a
hotter round, but when I reloaded the ammo and stuck to the lighter loads, I
had no problems.
Also, I noticed when I ejected rounds from the gun, the
first part of the neck seemed to get bent just a little. I think that the
case was comming in contact with the top of the reciever and causing
problems - very likely be the cause of eliptical necks
I think that the Schmidt Rubin is a very interseting rifle and I would love
to see a m1931 which has a shorter reciever and better supported bolt face.
For more info on the Schmidt Rubin check in a copy of Small Arms of the World.
Tom
--
Tom R Dennis
goo...@iastate.edu
John H. LeBourgeois
#In <940228163...@mentor.cc.purdue.edu> WAM...@PURCCVM.BITNET writes:
## I purchased a M1911 Schmidt-Rubin rifle about 4 months ago at a local
##gun show. This rifle had been sporterized and converted to .308 win. The
##dealer said that many of these rifles were converted in the 1950's after
##they were imported. According to him the rifle was rechambered to .308 win
##by the importer here in the states. This rifle shoots 1" groups at 100
##yards and it looks very excellent.
## I have some questions:
## 1. Doses anyone know anymore about these rifles? I know that the
## balistics of the 7.5 x55 Swiss are almost identical to the .308
## win, but is the bolt mechanism on this rifle strong enough for
## modern .308 amo?
#I don't have much specific experience with this action, but I have see
#information in the American Riflemen regarding Schmidt-Rubins which
#blew up after being converted to .308. I don't remember if the problem
#was the action or the mechanics of the conversion.
## 2. After I fired the rifle, I examined the spent cases. I measured
## them with a micrometer and fount that the shape of the case was
## eliptical rather than round. Does this effect the safety of the
## rifle? Should I bother to have it fixed by a Gun Smith? Is it
## fixable?
#Share your measurements. How eliptical. If the chamber is not round, and you
#want it fixed, you are going to have to rebarrel the gun. If its not very
#eliptical, it might not be much of a practical problem. Many chambers are
#somewhat out of round or non concentric with the bore, but there are limits.
#If it were me, I would probably pass on this gun.
#regards, Ken Karcich
##
## I would like any information or opinion that anyone might have
## Thanks
You need a concentricty gauge to measure the run out before and after you
shoot the rifle. Place an index mark on the the case head before you test so
you'll have a reference point to locate from. Fire several rds and average
the point of largest deviation. If it is consistent with the index then
you've got an eliptical chamber. If it is not, then the brass is
questionable. 15 thousandsth in a military rifle is probably not too bad.
Any more than that and I would consult with a gunsmith
Gary Coffman
# I purchased a M1911 Schmidt-Rubin rifle about 4 months ago at a local
#gun show. This rifle had been sporterized and converted to .308 win. The
#dealer said that many of these rifles were converted in the 1950's after
#they were imported. According to him the rifle was rechambered to .308 win
#by the importer here in the states. This rifle shoots 1" groups at 100
#yards and it looks very excellent.
# I have some questions:
# balistics of the 7.5 x55 Swiss are almost identical to the .308
# win, but is the bolt mechanism on this rifle strong enough for
# modern .308 amo?
# 2. After I fired the rifle, I examined the spent cases. I measured
# them with a micrometer and fount that the shape of the case was
# eliptical rather than round. Does this effect the safety of the
# rifle? Should I bother to have it fixed by a Gun Smith? Is it
# fixable?
#
# I would like any information or opinion that anyone might have
I dimly recall a *warning* published in the American Rifleman back in
the 1960s that these conversions were *UNSAFE* with 7.62 NATO loads.
The standard 7.5x54 190 gr bullet military load develops only 37,000 PSI
while the military 7.62 NATO works at 55,000 PSI. I also dimly remember
that it's easy to assemble the bolt incorrectly so that it does not *lock*
in battery. Hence you could wind up *eating* the bolt. I may be confused
about this latter bit of info.
You don't say how much out of round the spent brass measured, a couple
of thousanths probably isn't important, but grossly out of round conditions
could lead to severe gas leakage or case splits. I'd definitely have it
examined by a gunsmith qualified on the type before firing it again.
Gary
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