6.5X55 bore dimensions - Swede mauser
bill novak
Anybody slugged their Swede?
My rifle shows signs of headspace / pressure problems, so I slugged the
bore.
It mic'd .256 / .261 grooves/lands. Is this normal, or on the tight side?
Even lead bullets are sized to .264.
Any idea where on the net these barrel dimensions can be found?
Thanks
Bill
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Terry
"bill novak" <bnova...@wowway.com> wrote in message
news:g7vsvb$4pb$1...@grapevine.wam.umd.edu...
# Hi -
#
# Anybody slugged their Swede?
#
# My rifle shows signs of headspace / pressure problems, so I slugged the
# bore.
#
# It mic'd .256 / .261 grooves/lands. Is this normal, or on the tight
# side?
# Even lead bullets are sized to .264.
#
# Any idea where on the net these barrel dimensions can be found?
#
# Thanks
# Bill
#
Just for kicks, 6.5mm equals 0.25592 inches. O.264 looks awful big, 8
thousands is a lot to swage down in that long bullet. But for me this is
just a thought exercise, I don't reload for that.
TerryS
Robert Hankins
surp military, factory comml or your own reloads? To answer your specific
question, rifling specifications for an acceptable military barrel are:
land/land = 0.256; groove/groove = .263. Reference 'The Swedish Mauser' by
Kehaya and Poyer.
If you are reloading for a military barrel, take care with muzzle velocity
as the twist rate using a 140gr bullet will not stablize that bullet at much
above 2500 fps. What are you observing as to 'high pressure/headspace' ?
Bob Hankins
Chevguy
While I have not personally slugged mine, I do have literature on the
originals. Basically the "acceptable" range for the armory inspection was
from 6.46 mm (or .254") to 6.59mm (or .259") when it was taken out of
service. I know that mine (before a gunsmith possibly ruined it for life)
didn't like high pressure loads either. The 7.5" twist is probably another
factor. ( Hey, when you were in a time when you were still shipping a lot of
supplies on horseback, you made due with the technology you had!)
Ron Bloom
# bore.
#
What were the problems specifically? Did you load the ammo?
# It mic'd .256 / .261 grooves/lands. Is this normal, or on the tight
# side?
# Even lead bullets are sized to .264.
#
# Any idea where on the net these barrel dimensions can be found?
What does the brass disc on the stock say?
--
Ron Bloom
Sic Semper Tyrannis - Thus Always to Tyrants
Collector of Military Curio & Relic Firearms
sta...@prolynx.com
there, there should be a disk on it with the bore/groove dimensions
stamped on it as of last arsenal inspection. In millimeters, of
course.
Stan
bill novak
It's an M96 - with the original barrel and mil-surp ammo, the primers seemed
to
be flattened, and the bolt was really hard to get open after firing.
I got a new barrel from samco when they were selling swedes, and had that
put
on ..... the guy that did the work said he didn't headspace it quite right,
but that
I could fire form the brass and it'd be all right. He wasn't fibbing. I
got a set of
headspace gauges, and found it .008" over standard. Now I wish _he_ had a
set
of gauges when he did the work.
As a last resort, I suppose I could turn the shoulder and barrel face down,
and
re-cut the chamber.
I'v tried mill surp and commercial, and they both exibit the bolt opening
problem
on the new barrel.
I'm going to try handloading it, using the fired commercial cases, and just
neck
sizing them. But when I slugged the bore, It looked pretty
tight. I've got a lyman 150 gr. mold, and the slugs are pretty long, and it
took some
force to get the slug into the bore. That's what lead me to ask about bore
dimensions.
I intend to live within the limitations of the design pressures ... 1902
dated action,
but I really don't want to shoot something that is really unsafe, even if
I'm not loading
it to the design max.
Thanks for your responses. They've been helpful.
Best Regards,
Bill
"Robert Hankins" <easy...@bellsouth.net> wrote in message
news:g81afs$k8k$1...@grapevine.wam.umd.edu...
> ...
Ron Bloom
Do you have the same problem when you use brass that was shot in that
particular rifle with neck sized brass? You shouldn't. That is the only
alternative I can think of aside from taking the barrel off, shortening the
chamber and re-reaming.
Robert Hankins
separations by now. Take a piece of light wire like an unfolded paper clip
and feel down the inside wall of the fired cases. You might feel a 'nick' in
the wall above the case head which will tell you that you have the beginning
of a head separation. Since your mil surp ammo is no doubt Berdan primed,
you will throw them away anyway so no big loss. I recommend that you do have
the barrel set back and then re-cut the chamber so as to get into SAAMI spec
range. You need someone with a good chamber reamer.
Also, if you have good set of 6.5x55 full length dies, remove the decapping
pin assembly and use the sizing die to full length resize your loaded mil
surp ammo so as to bring the head of the case into SAAMI spec diameter. This
should help you with extraction problems.
Don't worry about the strength of a M96 action. I use a 1908 M96 action with
a new Krieger 6.5 with 1:8 twist and a McMillan stock (6.5x55) as a long
range target rifle and doing pretty good with it. My reload is a 142 gr
Sierra MatchKing bullet in a Lapua case; Win LR primer and 45.0 gr of
Hodgdon 4831 SC powder for approx 2760 fps. No signs of pressure or extract
problems.
Bob Hankins
RosemontCrest
http://dutchman.rebooty.com
The best discussion forum for military Swedish Mausers -- including
reloading data -- that I know of is:
http://forums.gunboards.com/forumdisplay.php?f=49
RosemontCrest
# Yup, was just thinking the same. If the military stock is still on
# there, there should be a disk on it with the bore/groove dimensions
# stamped on it as of last arsenal inspection. In millimeters, of
# course.
What is marked on the disk represents only the assessment of the
arsenal inspector at the time the rifle was last inspected; That may
have been 50 years ago. Who knows how many rounds have passed through
the barrel since then and how the rifle was cared for? I never rely on
the stamps on the disk of any Swedish Mauser to assess the current
bore condition.
Ron Bloom
# Also, if you have good set of 6.5x55 full length dies, remove the
# decapping
# pin assembly and use the sizing die to full length resize your loaded mil
# surp ammo so as to bring the head of the case into SAAMI spec diameter.
# This
# should help you with extraction problems.
Since the barrel is supposedly new and you do not know how it has been
stored, I would also look at the chamber being rough as a reason for rough
extraction. How do the cases look after firing? Is the exterior rough or
smooth?
sta...@prolynx.com
# Bob -
#
# It's an M96 - with the original barrel and mil-surp ammo, the primers seemed
# to
# be flattened, and the bolt was really hard to get open after firing.
#
# I got a new barrel from samco when they were selling swedes, and had that
# put
# on ..... the guy that did the work said he didn't headspace it quite right,
# but that
# I could fire form the brass and it'd be all right. He wasn't fibbing. I
# got a set of
# headspace gauges, and found it .008" over standard. Now I wish _he_ had a
# set
# of gauges when he did the work.
#
# As a last resort, I suppose I could turn the shoulder and barrel face down,
# and
# re-cut the chamber.
#
# I'v tried mill surp and commercial, and they both exibit the bolt opening
# problem
# on the new barrel.
#
# I'm going to try handloading it, using the fired commercial cases, and just
# neck
# sizing them. But when I slugged the bore, It looked pretty
# tight. I've got a lyman 150 gr. mold, and the slugs are pretty long, and it
# took some
# force to get the slug into the bore. That's what lead me to ask about bore
# dimensions.
#
# I intend to live within the limitations of the design pressures ... 1902
# dated action,
# but I really don't want to shoot something that is really unsafe, even if
# I'm not loading
# it to the design max.
#
# Thanks for your responses. They've been helpful.
#
# Best Regards,
# Bill
#
If the barrel has been replaced, there's no telling what you have
there. I just assumed it was the original one. Is the replacement
even military? Literally tons of aftermarket barrels floating around
out there in lots of calibers other than the originals. The bore
dimensions that were posted made me think of something in .25 caliber
like .257 Roberts. But I just assumed it was the factory original
barrel, so discarded that. Might be a chamber cast is in order.
A lot of guys that have worked on only commerical actions don't
really know how to rebarrel a Mauser, even though it's easy. The
barrel is seated on the chamber end of the barrel, not the barrel
flange, there's an internal ring forged and machined in the action for
just that purpose. Makes it easy, just make sure the gauge(or
cartridge) sticks out of the new barrel as much as it does out of the
old barrel and screw the thing home. If the guy was used to
Springfields, Krags, Remingtons and Winchesters, they don't work that
way, you HAVE to have a short chamber and ream afterwards. The
concept with the Mauser was that the barrel could be pre-chambered at
manufacturing time and just screwed home when it came time to swap a
defunct barrel, same idea as with manufacturing BMG barrels. By and
large, military-made barrels WILL work that way, headspace still has
to be checked after the swap, but not usually reamed to size. If the
guy did any reaming on your barrel, you need to check for chatter
marks or even a jugged chamber, might be the cause of the heavy
extraction problem. Then you still get to pull the barrel. If you
want to shorten and rechamber, both the end of the barrel and the
shoulder flange need to be faced. Then make sure the end of the
barrel seats tight on that internal action flange. The flange on the
barrel is relatively unimportant.
Stan