THE HANDLOADING BENCH
308 Winchester Rides Again Part 2 By Laurie Holland
Issues
Before we get onto my experience with ‘Palma’ cases, there are one or two issues to address. One is primer type and cup strength. Unlike LRPs which all have 0.027” thick cups, SRPs vary by type and sometimes by make. Standard SR versions vary from 0.019” to 0.021” by make, but Magnum / BR models use thicker brass sheet for a stronger cup. Federal 205M cups are 0.0225” thick, CCI-450, CCI-BR4, and Remington 7½
The other issue to bear in mind is the mechanical ramifications from the use of the small diameter flash- hole. I covered this in my introduction to the 6BR some issues back but will repeat the salient points. While the ‘Palma’ case’s flash-hole is 1.5mm (0.059”) in diameter, the standard decapping pin used in sizer or dedicated decap dies is 0.0625”, so use of same in these cases will likely see the pin stick in the flash- hole, break, or if rigid enough to survive will do so by swaging the case.
You must get a suitably dimensioned pin if your 308W die set doesn’t come with the smaller type, as most
Lapua’s .308 Winchester brass seen on the left is one of several recent introductions by the Finnish company. Another is its superbly consistent .22-250 Rem brass (front right).
/ 7½BR 0.025”. I haven’t seen figures for the PMC/ Wolf (Russian Tula manufactured) SR and SRM but my experience is that the former is one of the most fragile types on the market, while the ‘Magnum’ is exceptionally ‘tough’, resisting cratering and blanking slightly better than the notoriously strong CCI-450/ BR4 models in my Savage 223 F/TR rifle.
Why is this an issue? For some reason, small primer cartridges are far more susceptible to problems caused by over-large diameter firing pin tips / slack pin to bolt-face fit than LRP equipped cartridges operating at similar pressures. This can be an issue if your F/TR rifle is based on a stock Remington 700 action, to a lesser extent the Savage PTA but won’t worry you if you’re using a Barnard or RPA model, or any of the specialist single-shot match actions from BAT, Stolle, RG Rifles etc.
won’t, moreover make sure to have spares especially as small-diameter pins are only 0.057”, a mere 0.002” smaller than the nominal hole diameter on Lapua brass and easily broken. If you deprime cases as a separate step using a dedicated die you must obtain a correctly sized rod/pin, the fixed-pin Redding model needing the optional .17/.20 calibre rod, Sinclair’s decap die also using a different stem plus detachable Hornady small diameter pins.
Sinclair International makes a special BR/PPC flash- hole uniforming reamer (#07-3000) that is inserted from the rear of the case and indexes off the primer pocket which works in this case and the PPC / BR / 6.5X47L. It increases the flash-hole diameter a little to 0.063”, as Lapua’s production tolerances are 1.5- 1.6mm (0.059-0.063”). If you use this tool on your
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