Just been round to a mates house and ended up discussing his reloads for F Class. He is using a Barnard action and has just been experimenting with distance off the lands and the effect on grouping.
It made me think. When my rifle arrives, ( Savage 12 FTR in 308) I will probably aim for a load of around 45 to 45.5 Grains of ADI 2208 with Berger 155 Hybrids. I hadn't really considered seating depths. I am restricted under Australian F class rules to ADI powder - 2206, 2206H, 2208, 2209, 8208 and a reasonable selection of manufacturers/types of 155 projectile.
Does anyone have a recommendation for seating depth /OAL (presuming land distance to be fairly uniform on this model) ?
Thanks
Farshot I have and have had a lot of Savage rifles, and I have found that when working up a load they generally like a jump of .022 off the lands, so my starting point is usually .018 and I go from there.
I also had one fluke that shot it's best at .080 with Sierra mk's I no longer have it but it was a 308win shooting 155gr. at about .5 at 100 yards.
FROGGY
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Do it today there maybe no tomorrow
Probably somewhere in between 2.775 and 2.8. Hodgon shows COAL for the 155gr Sierra Match King at 2.775, but the Bergers may be a longer bullet. I've been playing with the 175-180 Class stuff for the most part.
Thank you both. I have to say .018-.022 is further back than I anticipated. I was thinking of around .005. I guess first job is to find out where the lands actually are.
Of course if you jam it that tight with room temp loads make sure your ammo stays cool. My 12 (26" 1:10) likes .020" jump on my loads and you can feel the tighter fit on a sunny 90 degree day.
I am currently loading my 243 (not a Savage) pretty well no jump at all. I live in the tropics and have not noticed a difference at all in resistance, either on warm day or for the 2nd 12 shots - after the rifle and ammo have been in the sun. I do understand the burn rate for powder may change with temperature but have been totally unaffected by expansion to OAL.
Using the seating gauge of your choice (I use the Stoney Point /Hornady) and the bullet you will be using, get an initial measurement and record it. Load up 50 rounds of a known accurate load and seat all the rounds to touching the lands. Go to a range where you can shoot at least 100-300 yards. Take a loading press with your seating die, shell holder, calipers, ten targets and something to write with. Shoot five rounds with the bullets touching the lands on a target marked "0.000". Using your calipers, measure your seating stem height off the die body and write this number down. Adjust the seating stem down 0.005" and reseat five rounds. Shoot onto a target marked 0.005". Continue reseating five rounds an additional 0.005" each time until all 50 rounds have been reseated and shot on appropriately marked targets. Analyze your targets to see which seating depth works best for your particular barrel.
Check barrel wear every 250 or so rounds and adjust your seating depth as necessary to chase the land wear. Once I figured what bullet, powder, primer combination I wanted, I loaded up 500 rounds to touch the lands and mark my ammo box as such. When I get ready to go practice or to a match, I reseat the bullet to the depth I want and then mark the box and go to the range. I've been shooting and competing for 30 years and this method has been the best I have found to date.
Even after replacing barrels on my match rifles, I can usually keep the same powder load, but I always have a different COAL. Hybrids in my rifle like to be anywhere between 0.002 off to .060 off the lands.I will probably aim for a load of around 45 to 45.5 Grains of ADI 2208 with Berger 155 Hybrids
The above load is common with 155 bullets. Go to 175's and 185's, you need to start off around 42.5 and work up.
Dennis
That is interesting. I'm all ears. The LR instructor where I was shooting at was the one that brought it up and was keeping his ammo under a white towel. After the third one I went back to my car (parked in the shade) and pulled a cooler ammo box and no problem. Next day went back to the originals without an issue.Originally Posted by FarShot
My son shoots the 12 BR model w/ a 1-12 twist. With a Lapua 155 Scenar here is what it likes:
155 Scenar
Lapua Brass
45.5g Varget
Most accurate .030" jump
Around 3,000 FPS in a 29" barrel
Most my fellow shooters close their ammo boxes between rounds just to shade a little. I am very slack on that and have on many occasions left the box open and the ammo sat for the half hour or so fully exposed to the sun. Second round the ammo is noticeably warm to pick up but seems no different on point of impact. I generally shoot a marginally better second round, I'm sure that is just all me. I am restricted in F STD here to ADI powders, and have of convenience used same in F Open. Maybe they are one of the powders that are not so temperature sensitive.
Thanks.
I finally picked up the rifle. My first load was 45.5gr ADI 2208 on CCI BR2 primers OAL 2.83 . Due to issues with the action seating not a lot to say about that other than it probably didn't group well. A friend gave me 5 of his rounds, 46gr ADI 2208 and seated on the lands, that was a one hole group at 100yds. due to current circumstances I'll be using factory match ammo for a couple of weeks and start ladder testing after that. As I said I am restricted to ADI powders due to F class Std rules here in Australia, however according to the ADI handbook it is equivalent to Varget.
Just to update this thread to match the other I started, The final 5 shots I had with my mates ammo turned out not to be enough to prove a group. Soon as I had more of them at next shoot I ended up with two groups or chasing zero just like I had with the prior 50 rounds. See http://www.savageshooters.com/showth...12-F-TR-issues .
This is NOT a load issue.....
My cartridge oal is around 2.78 with 155's
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