Need Load Data For Berger 215 Hybrid - 300 Weatherby

[Lrt307]

Berger load data is nothing more than starting points for us. Our accuracy and speeds are not on the same playing fields of the soft data they publish. Work up your loads in .5 grain increments to find psi. With large or over bore magnums I have many times found single digit deviation just under psi. This will yield good speeds, energy and accuracy.

I just got done reading some load data Berger published on the 300 RUM with a 180. It cracks me up they are showing a 96.7 charge of retumbo doing 29xx lol! We have setup dozens of 300 Rums with 97-97.5 grains H1000 running 185 vld doing 3350 on the slow side to 3400 fps.

Load data shows the 30 Nosler going faster than the rum lol!!! Nice botched info!

 

[Canhunter35]

I just got done reading some load data Berger published on the 300 RUM with a 180. It cracks me up they are showing a 96.7 charge of retumbo doing 29xx lol! We have setup dozens of 300 Rums with 97-97.5 grains H1000 running 185 vld doing 3350 on the slow side to 3400 fps.

Load data shows the 30 Nosler going faster than the rum lol!!! Nice botched info!

Lol shoot I'm running 200eldx at 2990, about 12es, with 86gr h1000, out of my 300wby. Sometimes it's nice to compare various load data sources

 

[MagnumManiac]

I found my 300 Weatherby performed better (accuracy wise) with the bullet seated at close to max mag length (- .010" of max mag length) with secant ogive bullets, which the 215gr Berger is.
The closer I got to the lands, the worse it grouped.
My throat is a parallel of .375" (3/8") and measures .30825".
My other Weatherby chambers have .500" (1/2") parallel of freebore and measure .0025" over bullet diameter, these are 340 & 375 calibre. Accuracy in these 2 are just as good. They both really like Accubonds.

My 300WinMag does the same with secant ogive bullets. Regardless of the tapered leade and long throat I built into this chamber. My parallel throat measures .220" after the taper and is .3085" for that distance.

Accuracy out of each rifle is sub 3/8 MoA if I do everything right.

Secant ogive bullets are less affected by jump distance than VLD type bullets.
This is why they get such good accuracy even with quite a jump.
If you follow Bergers directions on testing bullet jump, you should find the sweet spot in few components used.

Cheers.

 

[BLC3128]

I had the opportunity to head out to the range this past weekend. I shot 3-shot groups with the variable being the OAL. Here are my results.

DISTANCE: 100 yards
TEMP: 14
ELEVATION: 1560'
PRESSURE: 29.80
BRASS: NORMA
POWDER: RETUMBO (74.5gr) *min load according to Berger's manual*
PRIMER: FEDERAL 215

GROUP 1
COAL - 3.593"
AVG VELOCITY - 2,540 fps
MESUREMENT - 0.756"

GROUP 2
COAL - 3.633"
AVG VELOCITY - 2,551 fps
MESUREMENT - 1.166"

GROUP 3
COAL - 3.673"
AVG VELOCITY - 2,530 fps
MESUREMENT - 1.56"

GROUP 4
COAL - 3.693"
AVG VELOCITY - 2,565 fps
MESUREMENT - 0.468"

To get the barrel warm, I shot a 3-shot group that was just a tad over 0.30" @ 100 with box ammo (HSM Trophy Gold 210gr.) To my surprise the box ammo average velocity was 2,880, which is far below the listed velocity of 3036!

 

[BLC3128]

Update:
I had the opportunity to head out to the range this past weekend. I worked up loads with 2 shot groups to narrow down the sweet spots. The pressure signs came on slightly and I could have pushed it more, but I opted out of doing so.

 

[Canhunter35]

83.6 looks like the sweet spot to me.
83.3-83-9 only jumped 7fps

 

[BLC3128]

I cleaned the rifle and headed out Sunday to shoot 3 shot groups with the chosen combinations that worked the best, and I decided to work up and down by 0.1 grains to really find the sweet spot, nonetheless the velocities were a bit lower the next day..I will add that I did shoot a fouling group with box ammo prior to testing. I did notice that I was getting some flyers, most of these groups are as follows - two holes touching or almost and a flyer. ... I am opting towards loading up the more accurate combinations and shooting 5 shot groups. Any advice?

 

[Canhunter35]

The fact that 83.4 and 83.7 shot tight and 83.5 shot wide, convinces me your node is there. Something went wrong when you shot the 83.5 group. .2 grains makes so little difference when you case is holding 83+ grains of powder. I would go with 83.6 and fiddle with your seating depth if you want to tighten the group up