What level of accuracy for 338s

[distantfoe]

What kind of accuracy should one expect from a 338 lapua ~15lb "precision" rifle? I'm trying to tune my loads but .6moa is about as good as I'm getting. Begining to wonder if any more is obtainable from a 300gr bullet from a 10tw.

I've achieved some groups in the .3-.5 range but not consistently.

All groups fired from 250-320yds.

 

[wnroscoe]

Re: What level of accuracy for 338s

1-9.3 to 1-9.5 is best for the 300's. Your RPM's may not be where they need to be to fully stabilize those. I'd try the 250's and see what happened.

 

[STR]

Re: What level of accuracy for 338s

338LM can shoot very accurately consistently. Shooting some .3s and .5 groups doesn't happen by chance. This shows the rifle is accurate. The rifle stays the same, the shooter, and ammo can have more of an impact on accuracy from shot to shot. This is provided nothing changed with your rifle that you don't see.

 

[distantfoe]

Re: What level of accuracy for 338s

I believe I've found the problem. I'm trying to shoot bergers and believe others are having the same issue. Apparently there are issues with "nose slumping". I believe this is spot on as I'll have 2rds through the same hole and 1rd 3/4 moa out of the group. Occasionally, all 3rds would fall into the <.5moa range.

Shot some 300 smks, they shot absoutely lights out. Lets hope they get the bergers fixed.

 

[mdmp5]

Re: What level of accuracy for 338s

338 is the most forgiving round I have loaded for. Not powder charge or seating depth sensitive at all in my experience. It is a 1/2 MOA round at worst.

 

[triplecelectric]

Re: What level of accuracy for 338s

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: palmik</div><div class="ubbcode-body">338 is the most forgiving round I have loaded for. Not powder charge or seating depth sensitive at all in my experience. It is a 1/2 MOA round at worst. </div></div>

What loads are you using?

 

[mdmp5]

Re: What level of accuracy for 338s

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: triplecelectric</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: palmik</div><div class="ubbcode-body">338 is the most forgiving round I have loaded for. Not powder charge or seating depth sensitive at all in my experience. It is a 1/2 MOA round at worst. </div></div>

What loads are you using?</div></div>

To elaborate on my claim, I randomly chose 97 gr of H1000 under the 250SMK, mag length in my TRG at .025" from the lands. That was the first load I tried when I got my rifle. Turns out that load gets me close to 3000 fps, and about 1/2 MOA at 1000 yds. At 100 yds, it is a bit better than that, varying from about 1/4 to 1/2 MOA. I don't think I can ask for much more than that.

I still have to get a load for the 300SMK. I have shot 94 gr of Retumbo under them, but haven't recorded any data as of yet. I plan on shooting the 300s more often because of the better inertia in the wind.

 

[RBros]

Re: What level of accuracy for 338s

1-10 twist will work fine with the 300's, although now we are using 1-9.3 on all of our 338 builds. I see a slight bit of difference at ranges past 1500, but not really much closer. 100-1000 accuracy is almost identical. Here is a 300yd group from my personal 338 Edge with a 1-10 twist, BTW, the rifle weight 13.5lbs:

 

[DaveV]

Re: What level of accuracy for 338s

When I bought my rifle, it came with a batch of Barnes XLC's. I tried everything to get those to shoot and grew more frustrated after each session. Since I switched to SMK 250's, I have consistently shot sub-MOA. My best group is in the .3's. If I do my part, I believe I should be able to shoot .5 every session, even though my personal goal is to be MOA. The SMK's are very forgiving of powder differences and seating depth. I have been tempted to try some AMAX, Berger, Barnes Triple X, etc. loads, but I keep rolling back to the old "if it aint broke, don't fix it" mode. With a consistent baseline load, I can work on me. Maybe I'll try some flavor of the year loads down the road. But for now, it's SMK's all the way.