What is .308 Palma?

[rox]

The term "palma" means quite a few things, but it all can be traced back to the competition that used to bear that name.

The match is still very much called the 'Palma'. It looks like the Palma teams will need sub-aqua training though; Belmont looks to be in one of the worst effected areas of Brisbane. Hope the range survives, as well as the poor souls who are suffering there.

[Laurie]

The 'Palma' name is owned by the US Palma Rifle team and the discipline's governing body and its use in any product names or marketing is controlled by them and as jealously guarded as any valuable commercial trademark. It is used by Sierra and Lapua for specific products developed in partnership with the Palma team, ie the two Sierra bullet models S2155 and S2156 and the small primer .308W Lapua brass that was developed at the team's request in 2008 and successfully trialled by its members during the following season. Lapua then decided to add it to its production list and put it on the market last year branded with the 'Palma' name with US Palma Council agreement.

Not everbody is convinced by small rifle primer in .308W arrangement - and note too, as it is an important feature - the small (PPC and BR sized) diameter flash-hole. It is not new as Remington produced thin-walled 'UBBR' .308W brass some years ago whose primary raison d'etre was for reforming to 6mm, 7mm etc BR and similar design cases, not then available. This set-up is marginal for some powders and low temperature usage with 45-50gn charges in .308W. In normal temperatures, it has been proven as Stuart says to reduce MV extreme spread values by on average a third with the standard US Palma load of 155gn SMK + 46-47.5gn Varget.

A distinct downside of any high pressure cartridge that uses a small rifle primer is that you suffer cratering and piercing far earlier than with a standard large size primer. Magnum / BR primers are essential (thicker cups than standard SR models), but even so, rifles using Rem 700 type factory actions will see problems at relatively modest loads unless the firing pin is turned to a smaller diameter and the bolt body bushed. Since most TR, Palma and F/TR shooters are using BAT, Barnard, RPA etc custom actions, this is not an issue for them. The Savage PT action is far better than Remy and most other factory actions, but is still likely to be marginally affected at peak pressures. It does stop you 'overloading' the cartridge though and as Vince (Gun Pimp) says, this is a big attraction to F/TR shooters using really heavy loads.

With it being made in much smaller quantities than standard Lapua .308W brass, it is considerably dearer, which in the circumstances is to be expected. On the plus side, as a premium product made on new forming dies, it is very consistent neck thickness wise etc, even by Lapua standards.

Some of our Match Rifle guys have tried it - the extra case-head strength and promise of MV ES reduction is very attractive on the suerface to people shooting this 1,000yd + distance discipline. They have reported negatively though as they find MVs plateau at a certain charge weight level in their 190-210gn bullet / Viht N550 loads and that they cannot achieve their usual MVs (which are really something in these specially long-throated rifles). My initial tests in a Barnard F/TR rifle are showing something similar. What other F/TR users are saying is that (a) you cannot 'over-load' them (going by primer condition) and that as Gun Pimp says you can get up to similar MVs as previously achieved with LR primer brass, but the pockets stay tight for more firings thanks to more metal in the case-head.

One thing to note - and I suspect many purchasers will fall foul of this - is that .308W dies invariably have a decapper pin dimensioned for the standard 0.080" dia. flash-hole size. Resizing these cases wihout changing to the small dia. pin as used in BR / PPC dies will create problems. If the pin doesn't break / stick in the hole, it will swage the hole to a larger diameter - and this will INCREASE MV spreads!