Column Projectiles

Hi all

I apologise in advance if I'm beating a dead horse, but I posted in 1000/600 yard Benchrest about "projectile" choice for 30 cal and had a reply that seemed odd and I've only just figured out what it was about from reading this thread.

Andy started this thread and he's from the same country as me. This is a link to the Standard Shooting Rules of the National Rifle Association of Australia: http://www.nraa.com.au/pubs/SSRs.pdf

In 3.4 Ammunition and Components the NRAA refers to "Handloading Components... Projectiles". Appendix 1 with Reference to Chapter 3 describes "Approved Cartridges, Projectiles and Powder".

The NRAA rules cover Full Bore, Service Rifle, Field Class, Match Rifle, Long Range Blackpowder, F-Class, 300 Metre ISSF and 1000 Yard International Benchrest. I don't care for what Google or Wikipedia turned up - I've been a fully paid-up, card carrying and competing member of the NRAA for years and I support their use of the term "projectile" in place of "bullet".

I suspect a lot of people, at least in Australia, refer to loaded ammunition as "bullets", despite the fact they should/could know better, and the NRAA has decided to use an unambiguous term to clarify this. Unambiguous in respect to rifle ammunition - no one mentioned shooting bloody chairs. Out of bloody rifles?!? The internet is universal. Be tolerant and not an a$$.

Regards
Ben
 
Hope I didn't remove any useful information in my attempt to civilize this thread. I did leave a few "dangling" posts because I thought they needed left. That to explain to the late comer why some stuff doesn't seem to belong....
 
Wilbur thanks I was able to find the very useful information that was buried in this thread........post 61 became post 11........Ian
 
Al Nyhus said:
Andy, as a bullet maker I know my dies produce excellent bullets when the top of the core ends up in a specific range (as measured from the top of the jacket after the core is seated). For the purpose of this explanation, we're obviously talking about identical jacket lengths with just the allowable mfg. tolerances in length (a few .001's at most). many of us refer to this area as the lead line...where the lead core stops.

To keep a specific 'exact' finished bullet weight means that as jacket weights vary in different production lots, the core weight needs to be adjusted to compensate. The core weight is changed by making the cores a different length (jacket weight + core weight = finished bullet weight).

Rather than chasing our tails tailoring core weights to jacket lots, many of us allow the finished bullet weight to 'drift' from jacket lot to lot as long as the top of the seated core ends up in that specific range.

This lead-line sweet spot (for lack of a better term :)) is specific to each set of dies and is probably a function of ogive shape and relative to the diameter. A good set of .30 cal. dies might have a wider sweet spot than a set of 6mm dies, for example....depending on the bullets ogive, etc.

For a big volume bullet maker, the advantages are numerous and obvious. And the shooter gets an excellent product that's proven to perform.

I guess a lot of us have been making column bullets for a long while........we just didn't call 'em that. ;) :cool:

Good shootin'. :) -Al

P.S. As to being taken to task for your terminology, those posts remind me of this quote:

"I'm all in favor of keeping dangerous weapons out of the hands of fools. Let's start with typewriters."
- Frank Lloyd Wright (1868-1959)
Click to expand...

Al your post is very informative, I assume the "lead-line-sweet-spot" varies for each die and it's a matter of finding that spot. If you had two dies that are the same caliber and ogive would that sweet spot be the same for each die or would it be different for each die?..........Ian
 
Ian_Owen said:
Al your post is very informative, I assume the "lead-line-sweet-spot" varies for each die and it's a matter of finding that spot. If you had two dies that are the same caliber and ogive would that sweet spot be the same for each die or would it be different for each die?..........Ian
Click to expand...

Ian, I have two .30 cal. dies that are identical except for the finished shank diameter (nominally .3084 and .3090, respectively). The l.l.s.s. ;) is identical for both dies.

I'm a little guy bullet maker, a one trick pony (.30 cal. flatbase) and don't have any experience with 22's, 6's or boat tails.

Good shootin'. :) -Al
 
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