Spanish Mauser (in)accuracy
Tom
The bore was dark but after several hours of brushing, chemicals, and cleaning
solvents it is shining up nicely and now just has traces of copper in the grooves.
The rifling is crisp, the crown looks fine, and all of the furniture is tight. Headspace
was checked by the reputable seller and said to be acceptable. I have ordered a
gauge to recheck it, and to have on hand as I have done with all of my old mil rifles.
However, accuracy is less than sterling with an occasional 3 round 2-3 moa group
followed by 5 to 6 inch flyers in any/every direction.
The rear sight is a Lange Vizier (rollercoaster) with some vertical slop that forces
me to push it down after every shot. I have ordered a Mojo peep that is a close
fit (M44) and which should alleviate that annoying problem. One hopes.
I intend to remove the top handguard to see if that is the source of the flyer
trouble. When the new sight arrives I'll do that test.
All of the rounds I am shooting are handloads in three different bullet weights:
115gr, 139gr, and 154gr. These were all loaded into new R-P brass, which
was sized before firing. All of the loads act the same. After firing, the brass
looks fine with no pressure signs.
The chamber has lots of free bore and I did change one load to tighten
that up but it made no difference. I am not sure that I want to push that
too far. Any advice on that? In these old rifles, how tight is too tight?
Ten, twenty, thirty thousandths?
I have not slugged the bore. Doing a muzzle bullet check with all three of
the bullet weights indicates a nice, tight crown. That is to say, it does not
"swallow" the bullet.
Anyone have any ideas about improving accuracy consistency?
I am not looking to make this more than it is other than getting to an
reasonable level of consistency.
Thanks,
Tom
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sta...@prolynx.com
dimension. The chamber is probably cut for the oldest ammo they issued
which was a long round-nose bullet, not a spitzer, the reason for the
"freebore". Not a whole lot you can do there short of setting back a
turn and rechambering. Also check the twist, it might be more suited
to that old long, heavy bullet than lighter spitzers. Your fliers
sound like that might be the case. IIRC, that old round-nose was in
the neighborhood of 175 gr.
Stan
penultimate
> ...
Tom:
Obviously, there are lots of reasons why a rifle might shoot poorly
and loose or unstable sights would surely be among those. But I
suspect the cause for your "flyers" will be found amongst the issues
which should be got right from the beginning with any old rifle,
military or otherwise.
If your rifle was mine, the first thing I would have done before
shooting (in addition to the things you say you have done) is
completely disassemble the rifle for a thorough internal cleaning and
inspection. Most often you will find a generous amount of hardened
crud that was once grease on the action. I don't know if a careful
cleaning always makes the rifle shoot better. But it makes me feel
better and is necessary to reveal problems that definitely hurt
accuracy. As a safety consideration, I inspect the receiver with a
loupe looking for evidence of any hairline cracks. I usually fully
clean-up and re-lubricate the trigger assembly.
The stock gets lots of attention to because it effects accuracy. I
carefully inspect every square millimeter of interior stock inletting,
gently scraping loose any obvious build up of dried grease and dirt.
In particular, I look for any evidence of wood cracks or compression
damage from recoil at the tang and behind the recoil lug. Any obvious
problem usually merits at least repair with bedding compound. If this
is beyond your pay grade, show the problem to your gunsmith,
In a Mauser, it is important that inletting for the recoil lug be
clear so that the lug will seat completely in a stable manner. All it
takes is a dab of crud in the corner of the lug recess and the action
will not seat properly or the receiver will be torqued when screws are
tightened to join the action and stock. Ditto for the receiver
tang,
If a stock is warped so that it is pressing on the barrel where it
should not when the rifle is fired, this usually will reveal itself as
a shiny or worn spot. I sand such spots that might appear in the
barrel channel down a bit. When the stock interior is fully cleaned
up, I then reseal the stock interior by rubbing in a light coat of
boiled linseed oil. Do whatever else you might want to the stock for
cosmetic or clean-up reasons. If I am not overcome with eagerness, I
let the stock sit overnight before reassembly so the linseed oil will
harden a bit. Note that the interior of your stock now has a clean
surface with a dull sheen that will reveal where a barrel might be
thumping after the rifle has been fired.
Now comes the part that stands a good chance of being the cure for
your flyers. Note I can't recall for a Spanish Mauser if the top hand
guard assembles to (is wired to) the action before it is inserted to
the stock or is held in place by the barrel band. So reassemble in
accord with reality for your rifle, recognizing that I don't think the
hand guard has much to do with your flyer problem.
1. Remove the bolt and set it aside. By hand seat the action into
the stock and "feel" how it fits as it seats home before adding the
magazine box, trigger guard, and tightening any screws. It should fit
solidly and tightly. If it doesn't, a bedding job is probably going
to be an aid to best accuracy and MAY be necessary to prevent flyers.
Note that you have not yet fussed with barrel bands.
2.If the fit "feels" positive, hold the action seated home in the
stock with one hand while you mate the magazine box/trigger guard
assembly with the other. By hand, insert and start the threads for
the FORWARD trigger guard screw with your fingers. Using a
screwdriver that FITS the forward trigger guard screw slot, I then
tighten the screw to the point of obvious resistance with my right
hand WHILE STILL HOLDING THE ACTION WITH THE RECOIL LUG FULLY SEATED
with hand pressure from my left hand.
2.
penultimate
> ...
OOPS. my reply got posted before done! So this is a continuation,
given that I can not really see the part that "escaped."
Continuing and hoping this recapitulates enough that it syncs with
completion below:
1. hand seat cleaned up action fully into cleaned up stock.
2. while holding in place with left hand, thread in forward trigger
guard screw and take up slack to "almost" tight with screw driver.
3. Tighten the forward trigger guard screw fully, carefully watching
to see that the action seats fully into the stock. I have a torque
screwdriver and torque the forward screw on Mausers to the 40 inch
ounce setting. Without a torque screwdriver, this is quite firmly
tight but short of gorilla tight,
4. Attempt to wiggle the action in the stock. If the stock is not
tightly and firmly held to the receiver (with this single screw
tightened), stock wood has shrunk enough over the years that a bedding
job is necessary to get best accuracy.
5. Insert, thread, and tighten the rear (tang) screw into the trigger
guard. Watch if the action moves relative to the stock as the screw
is tightened. If it does, a bedding job (which includes the tang) is
probably in order. Note that I tighten this screw to 25 inch oz on my
torque screwdriver - which is "firm", but less so than the forward
screw,
The above seemed to "cure" enough inaccurate "old" rifles that I now
follow this routine before I waste any bullets. And it reveals a few
that are in need of stock repair or a glass bedding job. I'm not sure
this will fix your "flyer" problem. But I can sure create flyers just
by loosening stock screws on a rifle with a poorly inlet stock,
6. Complete reassembly of barrel bands, etc.
As to other causes, you are of course aware that the 7x57 was designed
with a very long 178 grain, round-nose, bullet in mind, which accounts
for lots of the free bore in modern loads. Your rifle probably has a
twist rate of about 1 per 8 1/2" (as opposed to modern US bolt actions
chambered in 7x57 which probably have a 1 in 10" twist). I'm not sure
your rifle will well stabilize the shortest of your loads. For
whatever it is worth, I have gotten best results in a 100 year old 7
x57 with Hornady 175 grain RN bullets loaded to about 2100 fps, a
bullet that approximates original design. I would give this bullet a
try, It is also a classic "cup and core" which is probably soft
enough to "bump up" if your bore is a bit over sized. Note that
European 7mm bullets are usually a little larger than (~0.001") than
US,
In and of itself, a long throat is probably not a sufficient reason
for your "flyers." But if we were to add a chamber on the large side
to a sizing die on the small side and brass on the thin side and maybe
some wobbly bullet seating, who knows? Chambers for cartridges from
this era are inconsistent and die manufacturers err in the direction
of sizing to fit the smallest that might be encountered,
Because I have Cerrosafe on hand, the next thing I would probably do
is a chamber cast, comparing the results to your sized brass (and the
latter to modern "SAAMI" chamber norms), You may have a chamber where
the neck sizing only and maybe even a degree of die customization is
necessary to get a good result, It is also remotely possible that you
have gotten hold of a "bad" die set.
Gunner Asch
> ...
Tom...Mausers can be prone to a host of issues causing such variable
accuracy. My gut feeling.....is that your stock/stock screws are the
problem. Pull off the upper handguard, check ALL the stock screws for
tight and see if you can pull a bit of thin brass shim stock down the
inside of the stock/barrel fit. Hummm...take a bit of matchbook, shim
stock etc and put a bit just at the front of the receiver..a temporary
"shim" and get the barrel out of the receiver a smidge by puttin in
enough shim. Fire 5 rounds and see if it improves your group. If
so..check for rubbing areas inside the stock/barrel junction.
Frankly...cringe...Ive found very few Mexican or Spanish Mausers that
will shoot worth a damned with the original stock, unless its been
cleaned out, glass bedded and then carefully remated..including the
handguard. They were not put together as well as the Swedes did theirs.
Shrug
Gunner
cameron.f...@gmail.com
> ...
Good info on the bedding. A lot of the ills of the free bore can be
overcame by the use of a Lee Factory Crimp die. This will give you
much more consistent pressures because it gives a consistent crimp, I
know it sounds a bit strange but in rifles with a good bit of freebore
I have had excellent results some have had their groups reduced by
1/2. though a smaller reduction in the group in the norm and fliers
have cleared up. It dose not help rifles where you can seat to the
lands but in my M48 it dropped my group size to 2 inches from 2.5
inches and with the layman receiver site that is as good as I can see
at 100 yards.
I would check and fix any bedding issues you have see what can be done
to the trigger then crimp your ammo Lee die in that order.
Tom
"Tom" <t...@att.net> wrote in message news:hivkcg$anj$1...@news.albasani.net...
#I recently acquired a 1926 version of a 1916 Spanish Mauser in 7X57 Mauser.
All,
Thanks for all of the great advice. I have it torn down and found several
suspicious areas in the stock channel that will be smoothed out. I will also
square up the slots in the stock for the receiver lugs and maybe throw some glass
in there as well for a nice, tight fit.
Some other comments:
With any new/old rifle I completely disassemble and clean/lube way before shooting it.
Under the stock is was remarkably clean, no gunk, no lube. Surprising, given its age.
This is my 5th Mauser (first Spanish though) and the others all shoot very well without
any changes to the stocks, etc. Lucky, I guess.
I always use a Lee Factory Crimp die for any crimping for all of my rifles, including this
one. I was gifted a set of Krupp 7X57 Dies from a shooting buddy neighbor and will
do the next resizing with those. The 1st batch was done with the Lee Pacesetter set.
I will have to do a bit more reading about twist rates and lighter bullets. I know of
the problem with slow twist and heavy bullets but don't recall seeing anything negative
regarding too fast twist for light bullets. The very long freebore could be taking a toll
on my lighter bullet batches' accuracy. If none of these changes help with eliminating
flyers I will go to a heavy bullet and keep plugging away. Oh, and I get somewhere
between 9.5 and 10 inches for the twist rate using a tight patch and rod.
There was a question re: the method of fit of the upper handguard. It fits into a
ring on the front of the receiver and is banded to the lower stock at the front of the
upper handguard. There is another band at the front of the lower stock which attaches
to the barrel about 5 inches from the muzzle. Neither of these bands is particularly
tight so some shimming may be in order.
I will try the front screw, rear screw receiver tightening order and watch the results.
Thanks for that tip.
I keep hearing about Cerrosafe and making castings and should probably have
been doing that with all of my old rifles. No time like the present to begin that.
I have a free week to play with this so should have some answers soon.
Thanks to everyone for your comments. I appreciate them all.
Kind Regards,
Tom
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