Lead-free primers

CCI and Fiocchi produce lead free primers, Fiocchi substituted diazole for the lead compound, and CCI uses diazole, manganese(iv) oxide, and aluminum.54... 

The use of titanium as a replacement for calcium silicide in conventional Sinoxyd primers is being investigated by Dynamit Nobel. Since they were introduced, lead free primers have improved to the extent that their performance rivals that of conventional lead-containing primers which they will probably replace in the near future. 

The residue on the surface of a discharged bullet appears to originate from the base of the bullet itself, from the primer, and from inorganic additives to the propellant. Firings numbered 8,21,34, and 35 had lead-free primers yet lead was detected on the perimeter of the bullet holes. Ammunition with barium-free primers gave barium on the perimeter. 

In more recent years there has been the development of lead-free primers based on the organic shock-sensitive initiator dinol (diazodinitrophenol) in place of the lead styphnate. Commercial formulations of dinoTbased primer have been developed which include mixtures such as dinol, zinc peroxide, metallic titanium, and tetrazene dinol, manganese(IV) oxide, and metallic aluminum and dinol, antimony sulfide, and barium nitrate. 

Figure 10.11). Concerns about lead toxicity have led to the introduction of lead-free primers, making the rhodizonate test less useful when such ammunition is employed. An alternative is rubeanic acid, which will react with copper.The copper originates from the cartridge casing, bullet, or primer casing, but not from the chemical compounds in the primer. 

Lead-free primers, created in response to environmental concerns, complicate the identification of GSR however, such particulates retain the physical characteristics of condensed metals. Table 10.4 summarizes key analytical findings relating to lead-free primers. Another alternative to lead styphnate as an initiator are mercury compounds, such as mercury fulminate (Table 9.4). Not surprisingly, little mercury residue is found in the GSR, due to the volatility of mercury. ... 

Oommen, Z., Pierce, S.M. Lead-free primer residues a qualitative characttaizafitm of Winchester WinClean, Remington/UMC LeadLess, Federal BallistiClean, and Speta- Lawman CleanFire handgun ammunition. J. Forensic Sci. 51,509 (2006)... 

Of course we exclusively use RUAG lead-free primers, Powers says. It is the only NATO certified lead-free primer in the world and we re the only company in the U.S. that can use this primer. That means no more light strikes or misfires. These primers eliminate airborne lead and reduce barrel fouling. Range operators have no hazardous breathing problems because it meets or exceeds all OSHA and EPA standards. 

CleanRange loads are designed to eliminate airborne lead and the need for lead retrieval at indoor ranges. CleanRange uses lead-free primers, but its lead core is copper jacketed for a fully encap-sulated bullet. This eliminates lead and heavy metal exposure... 

Lead-free primers have been available for about a dozen years. They address concerns over the lead and other heavy-metal compounds found in older primers. Original lead-free primers were less sensitive, but had a greater susceptibility to moisture and correspondingly shorter shelf life than traditional non-corrosive primers. 

Amplification of the DNA template is achieved by PCR (for details, see [14]). The size and amount of the PCR product should be routinely checked by agarose gel electrophoresis. An insufficient amount of product may be improved by increasing the number of PCR cycles. However, care should be taken not to overdo the cycling, because this leads to a loss of dsDNA after several PCR cycles the amount of free primers decreases dramatically so that only a fraction of the DNA template strands anneal with a primer and yield new dsDNA. The high complexity of the pool causes that ssDNA is not able to rehybridize with the complementary strand. 

Primer mixtures can be divided today into six categories (a) mercuric and corrosive, (b) mercuric and noncorrosive, (c) nonmercuric and corrosive, (d) nonmercuric and noncorrosive, that is, Sinoxyd type, (e) Sintox type, that is, lead free, and (f) miscellaneous (unusual priming compositions). 

The nylon-coated bullets from Smith Wesson and the Geco TMJ bul-let/new primer composition, although effective in markedly reducing the lead levels, did not totally eliminate the problem. In 1983, Dynamit Nobel introduced 9 mmP caliber ammunition with a TMJ bullet and a primer free of lead, antimony, barium. The new primer type was called Sintox. A typical Sintox primer composition contains 15% diazodinitrophenol (DDNP) and 3% tetracene as the explosive ingredients, 50% zinc peroxide as the oxidizer, 5% of 40-pm size titanium metal powder, and 27% nitrocellulose as propellant powder.202 As expected, other munitions manufacturers eventually introduced similar ammunition, some with primers that were lead free but containing antimony and barium and others free of lead, antimony, and barium. The objective was to produce ammunition which performed satisfactorily in every way and did not produce any toxic product on discharge. 

Red oxide primer 42 38 2 h 24 h Lead-free, general purpose, hard, water-resistant, anti-corrosive... 

Sinoxid = non eroding primer composition (german) 288 SINTOX = lead free priming composition (german) 289 Sixolite = tetramethylolcyclohexanol pentanitrate 310... 

Tetrazene is an effective primer which decomposes without leaving any residue behind. It is introduced as an additive to erosion-free primers based on lead trinitroresorcinate in order to enhance the response. Its sensitivity to impact and to friction are about equal to those of mercury fulminate. 

Typical primary explosives are lead azide and lead styphnate (see Fig. 1.17). The latter one is less powerful than LA but easier to initiate. Tetrazene (Fig. 2.2) is often added to the latter in order to enhance the response (sensitizer). (N.B. mercury fulminate used to be used as a sensitizer). Tetrazene is an effective primer which decomposes without leaving any residue behind. It has been introduced as an additive to erosion-free primers based on lead trinitroresorcinate. Unfortunately, tetrazene is hydrolytically not entirely stable and in long term studies decomposes at temperatures above 90 °C. Diazodinitrophenol (Fig. 2.2) is also a primary explosive and is primarily used in the USA. However, the compound quickly darkens in sun-... 

Features Lead-free chrome-free outstanding resist, to salt spray, rust creepage, flash msting stable nonreactive in pH-sensitive acrylic primers... 

To evaluate environmentally friendly processes for aluminum alloys, the improvement of the adhesion between a lead-free epoxy primer used in the automotive industry and aluminum alloy 6016 has been studied (Poelman et al., 2005). In particular the authors have compared samples pre-treated with a commercial Zr/Ti conversion coating with no pre-treated ones. 

Super Clean NT means lead-free and non-toxic. Winchester says this applies not only to the 100 percent lead free tin core bullet, but to the lead and heavy-metal free primer, also. Nevertheless, in a sign of the transition from lead to non-lead, the company notes that each of these cartridge/bullet combinations... 

Results from exposure corrosion testing show that aluminum surfaces prepared with a chromate conversion coating and a chromate-free primer perform much better than a chromate-free sol-gel type of conversion coating with the same chromate-free primer, " leading to the necessity for enriching the sol-gel coating with efficient inhibitors. 

Mahidhara, R. A primer on lead-free solder, Chip Scale Rev. Mar/April 2000, 4 (2), 40-41. 

DNA polymerases require a primer—a short, double-stranded region with a free hydroxyl group on the 3 -end of the shorter strand. The primer tor de novo DNA synthesis is a short stretch of RNA synthesized by an RNA polymerase called primase. The leading strand only needs one RNA primer, whereas the lagging strand needs many. 

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