Quoted:
I have used a lot of Wolf primers, and never had a single hang fire, misfire, or any other type of problem with them.  As already said, they do fit a little tighter (which is good in my book), so make sure they are seated all the way.

I was surprised on the varirations from one brand of primer to another brand, also the problems the shooter had with Wolf.

Quoted:



Wolf aside.

As for the variation.............How do changing various components affect chamber pressure and velocity?

www.frfrogspad.com/miscelld.htm#components  

Note: These results were typical under the conditions tested. Your firearm and ammunition may behave differently so don't use this as loading data.
Aloha, Mark

Is the variation in velocity with different primes due to one brand of primer being "hotter" than the other?
I was surprised to see  150 fps average difference from one primer brand to another......Win. 1892fps - CCI 1734fps.

Is the variation in velocity with different primes due to one brand of primer being "hotter" than the other?
I was surprised to see 150 fps average difference from one primer brand to another......Win. 1892fps - CCI 1734fps.

From: [email protected] (Bart Bobbitt)
Subject: Re: Accuracy via microprocessor control ?
Organization: Hewlett-Packard Fort Collins Site

J. Spencer ([email protected]) wrote in response to my comments
preceded by : #:

: #In reality, primers are more responsible
: #for velocity variations than powder
: #is.

: How, and why?

Because of the way the priming mixture is prepared and put in pellet moulds
then put in cups, anviled and sealed.

: If the manufacturers can get powder to burn consistently,
: and we can get consistent charges so that their effect is minimal, why
: can't the manufacturers produce consistent primers?

Primer mixture creation and processing is almost a `black magic' operation.
Few folks can uniformly put the putty-like substance in a totally
homogeneous form that's very uniformly mixed.

: And a related question: how do know
: that it *is* the primers, how has it been measured?

Measured by velocity standard deviation, using various primer makes/types
with different powder charges show that primers have the greatest effect
on uniforming velocities.

: That is one variable which we can eliminate, can't we?

Yes. Seat the bullet to where it pushes back into the case when it jams
against the leade as the bolt is closed.  That uniforms bullet jump as
leade/throat wear lengthens this part of the barrel.  You may need to
increase the powder charge weight by about one-tenth of a grain every
1000 or so rounds to keep velocity at the same level; otherwise it will
drop several fps as the leade/throat dimension gets greater.

: #Some powders tend to cause more muzzle velocity variations than others.
: #Extruded powder tends to be the most uniform; both benchrest and highpower
: #competitors favor this type over ball powder for this reason.

: It's just a bugger that it doesn't meter as well, eh Bart? :-)

Yes, but a charge weight spread of up to two-tenths of a grain doesn't seem
to matter much.

: #When the most mild and uniform primers are used, muzzle velocity standard
: #deviations can be kept to 5 to 7 fps.  That's a muzzle velocity spread
: #of about 16 to 22 fps; darn well good enough for even the most demanding
: #shooter.

: Really? I'm genuinely surprised at that (not to imply I'm skeptical,
: just surprised). Which primers do you recommend (for 243 and 30-06 if
: it's relevant)?

If you can afford 'em, use RWS 5341 primers.  Otherwise, Remington 9-1/2
standards are also very mild and work very well indeed.

BB
__________________________

From: [email protected] (Bart Bobbitt)
Subject: Re: [RELOADING] What makes Bench Rest Primers special?
Organization: Hewlett-Packard Fort Collins Site

`Benchrest' primers are typically more uniform in their ignition
characteristics than `standard' primers.  The process of mixing the
lead styphnate (the explosive), glass frit (the microscopic glass
particles that act as micro-anvils for the styphnate to compress
against) and a couple of other things is a kind of `black magic.'
About two quarts of this priming mixture is mixed together for each
lot of primers.  Getting the mixture homogenous (uniform percentages)
throughout the gooey mixture is difficult.  This mixture is spread
on a plate with little recesses in it that are the shape of the
primer pellet.  Getting exactly the same amount in each little round,
deep hole is also a type of `black magic.'  The mixture is much like
putty and a large putty-knife like tool is used to force the mixture
into each hole where it's left to dry.  Then the dried primer pellets
are punched out and put in primer cups, topped with a sealer, and
finally the three-legged anvil is pressed in place.

Interestingly enough, some folks do a better job of mixing and spreading
the mixture than others.  Within each lot of several thousand primers,
there's bound to be differences in the ignition characteristics from one
primer to the next.  As more care is needed to make `uniform' primers,
they usually cost more.

By uniformity, I mean the consistancy of velocity they produce.  Velocity
tests of the bullet is about the best test of primer uniformity.  Some
very uniform lots of primers will produce a velocity spread of only 15 fps.
At the other end of the spectrum are primers that produce velocity spreads
of 100 fps, or more.  Some folks have tested primer uniformity by shooting
BBs from a primed case (no powder) in a 17 caliber barrel; primers that
produce low velocity spreads with BBs do the same with powder and bullets.
Uniform primers tend to produce more uniform pressure curves, too.

Alas, not all the `benchrest' primers are as good as they're marketed to
be.  Many times a standard primer will be more uniform than benchrest ones.
And some makes of benchrest primers aren't as uniform as another make of
standard primer.  Even some standard primer brands are more uniform than
any benchrest brand.  Some benchrest primers are hotter than their standard
versions for the same make.

In many accuracy situations, a milder, standard primer will produce better
groups than a hotter benchrest primer.

BB