Developing a load 338 wm

[rjthehunter]

Fairly new to reloading so bear with me! I loaded from 67 to 76 gr of reloader 19 for my 338. I read from a manual that 66.9 grains is a good starting point for the bullet/powder combination. It calls max powder charge at 76. I've loaded like I said 67 up to 76 with 1 grain increments. I figure I'll start low and work my way up. Then once I have the most accurate load I can break it down to 1/2 grain increment increases/decreases.

10 grains just seems like a wide range between the starting and max load. I suspect I'll end up somewhere in the low 70s for an optimal charge. How do you guys go about developing a powder weight?

Some extra info if it matters. I'm seating my bullets 20 thousands off the lands. I'm only planning on shooting 3 shot strings. Once I narrow it down a bit I will jump up to 5 shot strings if I feel it's needed.

Thanks in advance!

 

[cahunter805]

What grain bullet and what bullet exactly are you loading?
Will you chronograph your shots?
Your powder charge range seems way to broad IMO.

I personally shoot a somewhat modified OCW/ladder test and then fine tune with seating depth at longer distance and minor powder changes.

 

[rjthehunter]

What grain bullet and what bullet exactly are you loading?
Will you chronograph your shots?
Your powder charge range seems way to broad IMO.

I personally shoot a somewhat modified OCW/ladder test and then fine tune with seating depth at longer distance and minor powder changes.

200 grain Hornady SST and yes I will chronograph. I also thought the range was really broad and that's really the reason for the post!

 

[mtmuley]

Why the SST? mtmuley

 

[cahunter805]

200 grain Hornady SST and yes I will chronograph. I also thought the range was really broad and that's really the reason for the post!

Seems RL19 will fill the case quite well might even be a little compressed. 72-76gr is what I’d test.
Do you have a bullet puller? I’d probably pull apart 67-70 or 71.

 

[Millsworks]

Once you have a powder charge that seems to be most consistent in velocity, and relative accuracy.....
You may try seating the bullet deeper in 5 thou increments.
Many times that will make a surprising difference.

And I happen to use that bullet in my .338 mag often. With very good results.
I prefer Accubonds, but the SST is no slouch in that cartridge, from what I have seen.

 

[rjthehunter]

Why the SST? mtmuley

I had recovered a bullet from a deer and the bullet expanded really well so I figured I'd start there. I'll order more bullets and try different things. Eld x and accubonds are on my list of bullets to find.

Seems RL19 will fill the case quite well might even be a little compressed. 72-76gr is what I’d test.
Do you have a bullet puller? I’d probably pull apart 67-70 or 71.

Yes it's definately compressed a bit. I do have a bullet puller and thanks for the advice. I'll probably pull those now.

Once you have a powder charge that seems to be most consistent in velocity, and relative accuracy.....
You may try seating the bullet deeper in 5 thou increments.
Many times that will make a surprising difference.

And I happen to use that bullet in my .338 mag often. With very good results.
I prefer Accubonds, but the SST is no slouch in that cartridge, from what I have seen.

I figured I'd start 20 thousands off the lands as I've read that's a good starting point. If I'm not getting results I like after finding an optimal charge then I'll play around with seating depth more.

 

[GunTruck]

I recommend MRP or RL26.

 

[dstefanie10]

Once you have a powder charge that seems to be most consistent in velocity, and relative accuracy.....
You may try seating the bullet deeper in 5 thou increments.
Many times that will make a surprising difference.

And I happen to use that bullet in my .338 mag often. With very good results.
I prefer Accubonds, but the SST is no slouch in that cartridge, from what I have seen.

I am reloading some longer bullets in my .338 winmag. With a 3.34 COAL listed for the caliber, would it be safe to use these longer bullets and end up with a 3.386 COAL? If I seat any deeper, I'll be seating on the ogive. thanks for any advice!