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"Old World Quality and Craftsmanship©"
BSR Custom Arms, a division of BSR Group, Inc. is dedicated to the repair, restoration and conservation of fine firearms and the fabrication of complete competition quality custom buildups, custom rifles (competition quality and field), and custom precision ammunition (both handgun and rifle) for competitive/professional shooters and the serious hunter. (See Section "What Makes an Accurate Rifle?" below and follow this link to "So, You Want to Build a Custom Competition Quality 1911 .45! ". Moreover, we offer custom stocks, checkering, carvings & engraving as well as custom hand/long-gun cases and cabinets. All work is directly performed or supervised by Wilhelm D. vonRothenburg, retired member of the United States Marine Corps competitive shooting team and member of the American Pistol-Smiths Guild. (See Home Page) Repair and conservation: Custom Gun building Complete Custom Rifles, Prices for our services may be found at the following
Links: An
accurate rifle will have a blueprinted (trued) action, properly fit barrel with
a concentric crown, trigger job, good bedding, and quality ammunition made
to match the chamber. The following
suggestions are developed from many years of experience as a full time
professional gunsmith. Maybe more
important is our experience in shooting and hunting.
The idea is to give you an overview of what it takes to build an accurate
hunting rifle. If you are looking
for bench rest magic that requires lots more time, and, money than the
suggestions below. Action
Tuning (blueprinting)
is the process of making all the parts that make up the action square and true
to the bore. First, the locking lugs of the bolt must be lapped to insure
even solid contact with the locking surfaces in the receiver.
When finished the lugs should have equal contact area and contact should
exceed 80%. This is accomplished
using professional lapping compounds that produce smooth even surfaces. Once the lugs are
lapped, it's time to face the receiver. A
precision mandrel is inserted into the action to hold it true to the axis of the
bore. The mandrel and action are
then placed on the lathe and a small amount of material is cut off the front of
the receiver where it will contact the shoulder of the barrel.
Only enough material is removed to square up the front of the receiver,
so no strength is lost. Then we insert the bolt
in the action and measure from the receiver face down to the bolt face.
We hold a standard for the bolt face of plus or minus .0005 inches across
the face. If this standard is held
along with the facing of the receiver and the lapping of the lugs, sub minute of
angle groups will result. In cases
where the bolt face does not meet this specification, we use a precision mandrel
and a steady rest to hold the bolt in a lathe to face the bolt face square. Barrel
Lapping is
available for new barrels upon request. Lapping
the bore can offer more uniformity, velocity, and accuracy.
This process removes the small burrs and marks left in the bore from the
machine process. It also polishes
the bore, which reduces fouling. A
side benefit is that, there is little or no break in for a lapped bore; this
saves lots of time and money at the range.
All the top match barrels are lapped; Hart and Lilja are two examples.
Barrel
Fit is the next
consideration. The barrel must be
set up on the lathe so that it is centered perfectly on the bore.
Centering the barrel on the bore insures that it will be mounted squarely
in the action. The shoulder will be
exactly 90 degrees to the bore and the threads will be concentric to the bore,
all are essential to accuracy. Equally
as important is the crown. It also
must be concentric to give best accuracy. Over
the years, we have tried many styles of crowns at many different angles to the
bore. Some work better than others
but the bottom line is always the same, if it is concentric, it will be
accurate. Trigger
Tuning can do
more for accuracy than you might think. These
days the factories are shipping guns with trigger pulls of five to eight pounds.
To add insult to injury they include lots of sear engagement
(shooters call that 'Creep'). Winchester and Remington triggers can be stoned and adjusted
to good hunting weights. There are
aftermarket triggers available for most actions these days.
Pull weights with these triggers vary according to the manufacturer and
or model chosen. Group size can be greatly reduced by a good trigger, just ask
a bench rest shooter.
Quality
Precision Ammunition
is a product of good reloading skills and tools.
There are many makers of reloading dies.
Quality varies widely from one manufacturer to the next.
All will work to produce usable ammunition.
Accurate ammo requires better quality dies. Just like the rifle, the dies must be concentric in order to
be accurate. Think of it this way,
if you were to draw a 12 inch long line on a piece of paper with a ruler held
firmly down you will get a single clean line from end to end.
What happens if you stop every inch and pick the ruler up, replace it on
the paper, and continue the line? Likely
no matter how careful you are the line will not be perfectly straight.
When we reload ammo, we are picking up the ruler with every component
used and with every process executed. Each component must be
as concentric and accurately made as possible.
This is why you often hear “reloaders” talk of using brass from 'one
lot,' it provides uniformity. Primer
pockets must be the same depth from case to case. The primer must be seated to the same depth on each case.
The cases must not be bent; some dies will actually bend the neck of the
case. Powder charges must be
carefully weighed so that each charge is the same as the last.
Good quality bullets must be used; if they are cheap, there is usually a
reason. Care must be taken when
seating bullets not to bend the case in the die.
Conventional bullet “seaters” will often bend the neck because the
bullet is not held concentric during the seating process.
Inline bullet seaters will solve this problem.
The idea is to hold the case and the bullet concentrically while seating
the bullet. The last consideration
is seating depth; here again uniformity is the name of the game. Seating depth is
established best by using one of the commercial devices available on the market
for this purpose. Once the seating
depth is established, start by seating your bullet .050 inches off the lands.
Do some shooting to find your most accurate powder and charge.
Once you have located a good load varying, the seating depth will help
tighten the groups. Start by
seating the bullet deeper by an additional .010 inches at a time.
Fire test groups, when you find the best group sometimes adjusting the
seating depth by .005 inches one way or the other will tighten the group even
further. Best accuracy usually
occurs between .050 and .080 inches. On
rare occasion, seating the bullet closer to the lands will be more accurate. I often hear shooters
talk about seating out the bullet to touch the lands of the barrel.
Bench rest shooter gets away with this practice because they are normally
loading at relatively low pressures. Conditions for bench rest shooting
also allow the shooter to spot problems that a hunter could easily miss in the
field. Seating to the lands is
OK for forming brass but is dangerous in hunting situations, as bullets can
stick in the throat when extracting live rounds.
In addition, pressure spikes can occur if the bullet is touching the
lands. Better consistency and
therefore accuracy will come from bullets seated away from the rifling lands.
Never seat any closer to the lands than you have to achieve accuracy. Custom stocks to match your individual pull, drop in your
choice of wood. Checkering (over-checkering), carvings, inlays and glass bedding. (Also See
Section "Custom Rifles".)
Custom Hand and Long Gun Cabinetry, to match any decor.
Federal Firearms License # - 35-33227 WE DO NOT SELL FIREARMS - HOURS BY APPOINTMENT ONLY |
