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View Full Version : 12 Palma and 175gr bullets



jeffjmr
06-16-2010, 09:33 PM
Newbie, here. Great forum. Lots of folks eager to help.

I don't yet have any bolt-actions besides my childhood .22 Marlin and my Chilean Mauser 95. I have shot Highpower matches with my M1A, and have pushed my Garand out to 500 yds+ as well and am now hooked on "lobbing". But I have been a Savage fan since shooting Savage/Anschutz Super Match 54's at camp as a kid.

I am close to "pulling the trigger" on a new 12 Palma. Hoping to do some F-class with it as well, I have been pleased to read the experts reporting that the 1 in 13" twist should be fine for the 168's and 175's. What I have not been able to discern is whether the short free-bore poses problems for loading the 168's and up. If it severely limits load/powder choices, I may have to rethink.

Anyone out there with the 12 Palma having used the bigger bullets?

Thanks.
Jeff

memilanuk
06-17-2010, 02:12 AM
Not as of yet. They shoot the new generation 155gr (long OAL, very short bearing surface) bullets like a friggin' house-afire, though.

rjtfroggy
06-17-2010, 06:16 AM
I am not new to shooting and or hunting but I never considered competition type shooting,but yesterday sifting through the Savage site I was intrigued by the Palma rifle. So can you tell me the difference between 308 and 308 palma, is it similar to being Ackley improved or what?

jeffjmr
06-17-2010, 07:28 AM
My understanding is the chambering is standard .308 Win EXCEPT that the free-bore is shortened to maximize performance with the International Rules limited 155gr. bullet (I think the rule is 156gr. max), and the twist rate is 1 in 13", also considered best for that bullet.

My question is just HOW short is that free-bore? Thus is the compromise necessary to shoot different disciplines with the same gun.

Jeff

DGD6MM
06-17-2010, 07:59 AM
I'd call Pacific Tool and ask them, they will be glad to answer you questions.

memilanuk
06-17-2010, 01:19 PM
The chamber used, IIRC is the Warner Tool Co. 1995 Palma chamber, aka WTC95 Palma, and is a very common chamber reamer used for Palma rifles. *Other* than the throat, it is just a bit snugger than SAAMI all the way around, taking up a bit of the 'slop'. The throat is pretty short, as it was designed for the 'old' Sierra 155 Match King model 2155 bullet at an OAL of around 2.800"... the new Berger 155.5 BT 'Fullbore' and Sierra 155gr 'Palma' model 2156 bullets are much longer, and have shorter bearing surfaces so they actually work very well with the chamber nearly as is, despite the loaded round having a longer OAL. As an aside, I've ran into more than a few places that had their own special 'match .308' chamber that turned out to be nothing more than a WTC95 Palma throated a little long for a S175MK to be seated at 2.810" and still be jumping a bit to the lands - its disturbing how accurate that combination can be!

The 12 Palma barrel also has a tighter bore diameter around .298 x .306", as opposed to the approx. .302 x .306" used in say, the 12 F/TR barrel. This is kind of a left-over from back in the days when 'issued' ammo was used in international matches, and some locales apparently had loose interpretations of what size .30 cal bullets should be. The tight bore isn't really necessary today, and when coupled with the short throat can serve to jack the pressure up in a hurry if one isn't careful. It's certainly possible to shoot longer heavier bullet through a tight bore barrel... but with the longer bearing surfaces of those bullets, I'd be extra careful in doing so.