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R.G. Robinett
1. What makes a bullet benchrest quality?
First and foremost, quality jackets - the less total indicated run out (TIR) the better. However, .0003" TIR jackets are acceptable. In fact, such jackets are non-returnable, as they are within tolerances for BR quality jackets. J4 uses .0003" as maximum runout and Sierra uses .0004" as the upper limit for TIR at the first datum point above the jacket base.
2. What equipment is needed to make benchrest quality bullets and where can I get the equipment?
1) A good set of dies - preferably carbide, especially if one plans on making bullets to sell. Carbide dies are less likely to become damaged and will make more bullets. For the individual who plans on making bullets for himself and a few pals, tool steel dies make excellent bullets and should last a life-time.
2) Converted press(es) - that is presses which have had the ram replaced to accept bullet making punches. Preferably, the presses will either be true, or have been trued by the converter/manufacturer.
3) Paraphernalia to straighten and cut lead wire into slugs for squirting. Most of the die makers can supply the dies and core cutting paraphernalia. Though 'squirted' (preformed) cores may be purchased, my experience is that such cores are never as uniform as I can squirt by hand - this does require time, but I prefer to know every bullet by its first, last and middle name.
In my experience, Bill and Brian Niemi make excellent carbide dies:
W.B. Niemi Engineering
P.O. Box 126
Greensboro, VT 05841
(802) 533-7180
3. What are the essential techniques for producing benchrest quality bullets?
Though somewhat outdated with regard to equipment, THE ACCURATE RIFLE, by Warren Page, and available again through Precision Shooting, is worth the price just for the bullet making comments offered by M.H. Walker and Emory Tooly; this info is timeless. I will not bore the reader with my own procedure.
Assuming good jackets, degreasing and core seating are, in my opinion, the most critical steps in making precision bullets. The cores must not slip inside the jacket. Never squirt cores using a lube containing silicone. Removal of silicone can be very difficult, generally requiring one of the hard to get chlorinated hydrocarbon solvents. Cores should be washed a minimum of three times, the final wash always being via NEW (unused) solvent.
Next, core seating must be done with a properly fitting punch. One must either have a selection of punches, in no greater than .0005" increments, or size the core to fit the punch/jacket lot. The latter option (one or a limited number of punches) mandates a willingness to vary bullet weight slightly. Upon seating, a proper punch will allow for a very small amount of the core to uniformly bleed by the punch when peak pressure is reached. This small gap between the punch and jacket assures that no air is trapped between the core and jacket.
Lubrication of cores and jackets should be CONTROLLED. Always weigh and record the amount of lube used for these operations - this facilitates trouble shooting and helps produce uniform results. Use the least amount of lube necessary to accomplish the desired task: i.e., for pointing, use the SMALLEST volume/weight of lube which produces the LONGEST finished length.
Experimentation with your dies and jacket lot(s) will be necessary to determine the proper amounts of lube. For core squirting, I use COOL TOOL II ( a cutting oil/cutting oil additive). For jackets (seating/pointing) I use a mixture of anhydrous lanolin and PURE Neatsfoot oil (one does not know what additives are present in the compounds) in a ratio of approximately 5:1. This results in a viscosity about like room temperature butter. It has proven to be a very reliable lube. Rich Griffen put me onto this a few years ago - very simple and no surprises.
I prefer to use a minimum amount of lube (on the jackets only) for core seating. I like a little ‘drag’ as the core seated jacket is ejected from the die. I add lube just prior to pointing. Doing this minimizes the likelihood of cores sticking to the core seating punch and also assures uniform distribution of lube for pointing.
Prior to pointing up, I de-lube the jar, apply the desired additional lube to the jar and re-tumble the cored jackets for five minutes. If the lube jar is not de-lubed prior to each tumbling session, the lube will build up, resulting in a drift away from the baseline. Keeping notes and weighing every time has proven beneficial. It also helps to control the temperature and relative humidity. Being ‘old fashioned, I allow cored jackets to rest for at least 24 hours before pointing.
Bullet making is neither complicated nor difficult, the making of precision bullets has not changed in about fifty years. We do have better 'stuff', but the principal remains unchanged. The 'secret' to making BR quality bullets is an UNCOMPROMISING penchant for details and application of common sense.
Get a copy of the ACCURATE RIFLE and get not only the specifics of how to make bullets, but also a glimpse of BR history.
Good luck and good shootin'.
R.G.R.
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