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From: (Bart Bobbitt)
Subject: 308 Win. Palma Loads
Organization: Hewlett-Packard Fort Collins Site

During the last four days of October, some US Palma Team folks met in Phoenix
to practice and evaluate coaches.  We used ammo loaded by Jensen's Custom
Ammunition on single-stage presses.  Here's the component/process list:

  * Winchester Palma case, new, but neck-expanded with a .3075-in. plug
    to uniform the case mouth and allow about 20 pounds of seating force.
    The mouth was slightly chamfered.  Case weight was about 166 grains;
    weight spread about 3 grains.

  * Federal 210M primers; a very uniform lot.

  * 44.5 grains of H4895 (Australian made) thrown from measure; charge weight
    spread of about .3 grains.  Muzzle velocity in the 29 to 30 inch
    barrels was about 2980 fps.

  * Sierra 155-grain Palma bullet seated to an OAL of 2.800 inches.

  * Bullet runout two calibers in front of the case mouth was .004-in., or
    .008-in. TIR, maximum; average was about .002-in, .004-in TIR.

This ammo shot very well.  Although no real test groups were fired, it was
estimated to shoot about 1 MOA groups at 1000 yards.  Eighteen shooters
consumed about 4000 rounds total.  The Krieger and Obermeyer barrels used
had groove diameters of .3065- to .3075-in.  Rifles were based on Win. M70,
sleeved Rem. M700 or Paramount/Swing actions; one Stolle action was used.
Stocks were either wood or synthetic materials; one was not better than
another.  When wind conditions were decent, the better shooters were able
to maintain about 10-inch vertical shot dispersion on the target.

Most interesting was the H4895 powder was fairly clean burning.  Powder
residue was small compared to typical IMR4895 powder lots.  Nobody cleaned
their barrels the first day firing about 80 shots each total.  On the
second day, we all cleaned at noon after about 30 shots each, then fired
about 30 more in the afternoon.  Accuracy improvement was not observed.
Folks shot about 60 to 70 shots each of the last two days and didn't clean
at all during the day.  Accuracy levels were maintained.  Cleaning patches
came out with some gray residue from the H4895 used, but not as much as
what IMR4895 typically produces.

In one of the discussions regarding the ammo, several folks mentioned that
it appeared to shoot better than the 1992 Palma ammunition used last year.
The consensus was that the main reason was due to single-stage presses
being used and the powder metered from a solid-mounted measure.  The Dillon
1050 metering powder and seating bullets had too much vibration due to its
mechanical case-moving plate to get reasonably-uniform powder charges.  As
that progressive loader cranked out near 400,000 rounds of ammo, over time
its ability to keep powder charges uniform deteriorated.  Ammo lot numbers
at the higher end tended to have a greater charge weight spread than lots
made earlier.  Several times, the 1050 had to be readjusted to keep charge
weights acceptable.  Ammo from lots known to not be good was taken apart
and charge weight checked.  The IMR4895 powder in some had a weight spread
of .5 to .6 grains; too much for acceptable accuracy.  Charge weight spread
in accurate ammo lots was about .3 grains.  Although primer lot uniformity
did vary somewhat and was noticeable, we now feel the biggest contributor
to inaccurate ammo was the powder charge weight spread.

We felt that progressive loaders may work reasonably well to make ammo for
use at short range, they must be solidly mounted and not operated erratically.
But the most accurate ammo is still made with single-stage presses.  And the
most accurate powder charges are thrown from a solid-mounted measure that's
operated uniformly for each charge.


From: (Bart Bobbitt)
Subject: Re: [RELOAD] Can a Dillon make match rifle ammo?
Organization: Hewlett-Packard Fort Collins Site

Donald R. Newcomb ( wrote:

: So, is there anyone out there building MOA rifle ammo on a Dillon?
: If so, how do you do it? As far as I can see, they are great for keeping
: pistols and machine guns fed but of limited value for rifle shooters.

Yes, there is.

Jensen's Custom Ammunition (Tuscon, AZ) used two Dillon 1050s to make the
1992 Palma Match Ammunition.  About 400,000 rounds were produced.

The first 300,000 or so rounds were pretty good stuff.  Although some
accuracy variations were due to the specific Federal 210M primer lot used,
most of the lots would shoot less than 1 MOA at 1000 yards; less than
2/3 MOA at 600 yards.  But the last 100,000 or so rounds were not quite
that good.  As the powder measure's automatic cycling was beginning to
be a persistant problem, charge weight started varying to have a .6-grain
spread.  That coupled with a not-too-good primer lot would just barely
shoot 3-foot groups at 1000 yards.  None of the folks getting one of those
bad lots of ammo shot good scores at the '92 Palma matches.  Fortunately,
good lots were used for the team match.

Some folks make highpower rapid fire ammo with Dillons and it does quite
well.  But the most accurate ammo is made with single-stage presses and
the powder is either thrown from a good measure solidly mounted separate
from the press or weighed on scales for long range ammo.


From: (Bart Bobbitt)
Subject: Re: [RELOAD] Can a Dillon make match rifle ammo?
Organization: Hewlett-Packard Fort Collins Site

Stefan ( wrote regarding progressive loaders
making match rifle ammo:

: See the latest issue of Precision Shooting.

Thanks for the advice.  My PS came yesterday; I read the article.

The article's author wrote about reloading for his benchrest rifle.  He
used neck-sizing dies and a powder that meters very uniformly with only
light torque on the powder measure's metering system.  In this environment,
I would agree that very accurate ammunition could be made with a progressive

But the processes, dies and rifle involved are all perfectly suited for
benchrest situations.  The amount of friction presented to the operator
to overcome is low.  Which means the critical part, powder charge uniformity
was easy to control.

Neck sizing reloads for highpower rifles, or match rifles (different from
benchrest rifles) has not proved the best for accuracy.  Several folks
tried full-length sized reloads with progressive reloaders such as the
Dillon 550 and 650 versions.  But those machines just have not quite
produced ammo equal to that produced on single-stage reloaders for accuracy.
The extra forces required for full-length sizing causes too much variation
in powder charge weight.

With decent quality new cases, progressive reloaders have produced very
good match rifle ammo that's performed very well at long range (800 to
1000 yards).  But only with heavy, massive progressive reloaders such as
the Dillon 1050s were used in pairs.  One resized the neck to uniform
mouth diameter and seated the primer.  The other charged the case with
powder and seated the bullet.  The ligher weight 550s and 650s vibrated
too irregular to keep uniform powder charges of the correct powder going
into the cases.

Heavy progressive reloaders have produced full-length size reloads
for short range (200 to 300 yards) that's almost as accurate as what ammo
prep'd on single-stage presses for the same ranges.  Again, these are the
Dillon 1050s.  This has been tried with the 550 and 650; didn't work.


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