A query about choosing an intial range of loads

[GarethMarijt]

Hi,

I have a Savage Model 12 F Class in 6 BR Norma (1 in 8, 30" barrel) and have recently bought some Berger 105 grains VLD. I am in a bit of a quandary as the the suggested loads seem to range between 29.0 and 30.7 grains of Varget. Berger Bullets advise on 29.1 as being the maximum (26 as the minimum).

I am new to loading for the 6BR and don't want to start at potentially .1 of maximum.

Any advice gratefully accepted..
Gareth

 

[Terry]

All of my 6BRs will take 30-31 grains of Varget.
The 30 grains listed on this sight under 6BR Cartridge has worked in them all.
I tune to 30.2-30.5 in the end.

 

[Erik Cortina]

Shoot one shot at each charge from 26.0 to 31 in .5 gr increments and stop when you see pressure signs. This will tell you the max in your gun.
Once you know the max, you can do a proper load work up.

 

[Hoier]

I do the same thing as Erik but in .3 increments.

 

[GarethMarijt]

Thank you all. I won't get a chance to try it until the end of next month. Once I know the safe limits, I am going to try Erik's load development advice.
Gareth

 

[savageshooter86]

Erik tough thing with Savage PTA is telling pressure. I have worked up last two bullets and only found pressure as I was about to blow primer(Actually did blow one). Was going in 0.3 increments and nothing felt different and primer on previous looked normal then all the sudden major pressure. Since Savages cock on bolt opening it is hard to tell anything at all

Even had 2 other reloaders checking each piece of brass and primers for me after I did as we worked up. We were all very surprised

 

[NorCalMikie]

IMHO, You'de be better off starting around 28.0 and working up. You'll find an accuracy node down around that charge and one closer to max. By starting lower, you'll leave yourself some "wiggle room". No use loading at a higher charge and having no where to go but down. And, your brass will like the lower charge.

 

[Lapua40X]

IMHO, You'de be better off starting around 28.0 and working up. You'll find an accuracy node down around that charge and one closer to max. By starting lower, you'll leave yourself some "wiggle room". No use loading at a higher charge and having no where to go but down. And, your brass will like the lower charge.

I'd have to concur with this approach. I shoot 107gr Sierra Match bullets. My 6BR found it's node at 28.6 grains of Varget. Yes, it's true that 28.6 grains of Varget doesn't take me into the realm of 3000 fps but 30 grains produce very obvious pressure signs in my rifle so I say away from there.
Seating depth will be another variable once you find a load your gun likes. If I set 107gr Sierras at 1.800 OAL my BR is a tack driver. Everything falls apart below the 1.800 until I hit 1.783 where it all comes back together. I'd suggest keeping in mind that faster doesn't necessarily mean better. Start low, work up to the point where you like the targets and play in that sandbox until everything comes into balance.

 

[ShootDots]

One B-I-G note you should keep in mind. Once you find MAX, do not shoot AT MAX even if it shoots great there. Find a W-I-D-E window of accuracy and stay somewhat "in the middle".. Example: let's say in your tests you find that 29.8 shoots GREAT. As you increase your charge towards maximum you see that at 30.7 you BEGIN to see signs of pressure. Work in .2grain increments from 29.8 to say 30.4 and try and find a really good load there. That way you are NOT pushing the envelope and temp swings will have little or no effect on your groups. Now it is fair to note that MOST V.L.D. designed bullets prefer a 10K+ set INTO the lands. This is a good place to start your VLD's, however, there can be rather large variations in where YOUR rifle likes them seated. My 6mmDasher PREFERS them JUST off the lands 2-3K off. Remember, setting them INTO the lands will cause pressure to increase somewhat. SO, with that being said, I would START off your "pressure / ladder" test with the bullets into the lands 10K or so.

 

[savageshooter86]

+1 If you start at jam and then find a charge, you should not get any more pressure than that unless you seat the bullet really far into the case and start to compress loads. Several top shooters have suggested this method to me and that is how I go about it now

 

[NorCalMikie]

What works for me:
I make all my loads with a jam "into" the lands. (custom or short throat chambers required)
You start seeing pressure signs at a given load setting with a "jump" to the lands. That same load set at a jam "into" the lands, won't show pressure signs and I can go higher in charge with no pressure problems.