338-8mm rem mag

[comen]

I just acquired a 338-8mm rem mag. Does anyone have load combinations they would be willing to share? Powder and bullet recommendations primarily, what you get for velocity (I have a 26" barrel)

 

[dogz]

basically it's a .340 Wby, back in the day when I was using the 340 a lot I formed a lot of brass via 8 RM

 

[MagnumManiac]

Back 340 Bee START loads off by 5% and start there.
The freebore of the Weatherby allows quite a bit more powder usage than a traditional throat.
When I was using my 340 Bee barrel a lot, it was only getting 100-150fps more than my long throated 338WM.
Do you have dies?

Cheers.

 

[comen]

Back 340 Bee START loads off by 5% and start there.
The freebore of the Weatherby allows quite a bit more powder usage than a traditional throat.
When I was using my 340 Bee barrel a lot, it was only getting 100-150fps more than my long throated 338WM.
Do you have dies?

Cheers.

No dies, but I just necked 50 cases up from a bag of New remington 7mm STW brass in two steps, first with an 8x57 M die, then a hornady 338 Win die. Made some dummies and they ran through the magazine and chambered freely. I set space for the sizing die and the seating die using a spare lock ring on each so I don't have to lose the existing 338 win adjustments. I loaded a ladder for 225 Grand slams with imr 7977 from 80 to 88 grains in 1 grain increments. I will try these tomorrow. I make brass for my 8mm Rem Mag the same way. My 8 mag load of 83 grains of 7977 under the 220 Sierra gets me 3011 fps from a 27: bull barrel. My big 8 weighs 16 lbs, so its a bench queen. The new rifle weighs 9 lbs 12 oz empty, with scope and sling. I am limited to 3.6" magazine length.

 

[comen]

For anyone who cares, I ran my ladder yesterday at 220 yards and found flatspots between 80 and 81 gr, and 86 and 87 grains. I will now shoot for group over the little Chrony, with 86-87.5 gr in 1/2 gr increments. The primers show a little cratering at even the lowest load, which does become more evident as pressures increase. The edges of the primers are still completely round, and I can flip open the bolt after firing with the back of my thumb with my hand still on the grip. The case necks were smoky until until 87 gr load showed clean. I can still hear a little powder shake in the loaded round even at 87.5 grains.

 

[comen]

Ran the groups from 86.0 to 87.5
1. 86.0... Av 2808, extreme spread 37 fps
2. 86.5... av 2790, extreme spread 7.7 fps (weird, Chrony malfunction??)
3. 87.0... av 2876 extreme spread 39 fps
4. 87.5... ab 2883 extreme spread 38 fps

I still have no pressure signs. I am now reshooting 87.5, and adding 88.0 and 88.5 grains all three loads with 5 shot groups. I can still hear a little powder shake in the case at 88.5 but I'm very near 100% load density.
I am limited to 3.6" COAL by the magazine, so I decided to find where my bullet contacts the lands as a single feed. I seated the speer grand slam out until I could just feel the slightest contact and found my length was 3. 859" I have a boatload of freebore which explains the relatively low velocities for the powder charge. I may have to find a bullet that is very tolerant of long jumps. Any recommendations?