Getting frustrated…. A little help with my precision loads - OCW!!!

[EXSOCAL]

I have never ever had so much frustration reloading for my .308 bolt gun. Back a few years ago when I started reloading precision ammo I had no problem loading ammo that held groups in the 3's and 4's all day long, every day - 44.6 gr Varget, Lapua brass, 175 SMK .020 off lands - this load was consistent and accurate everywhere I went. Fast forward 5 years. I had around 6k rounds down that original Krieger tube and found a nice new Bartlein barrel from Bugholes in a new contour I wanted and with 5R rifling so I snatched it up and sent it back to Long Rifles for the fit up. Some specs on the rifle - Surgeon 599 action, 26" Bartlein 5R 11.25" twist, M24 contour, Nightforce 5.5-22, NF rings, Manners T4A / Manners Mini chassis. Its a solid rig and very capable of great accuracy. I started with 20 rounds of virgin Lapua brass and 43GR Varget to break the barrel in and started right in on the load development. I ran 3 mirrored OCW's exactly by the book and came up with a pretty definitive node at 43.8GR Varget with the 175 Sierras. From here I ran a seating depth test starting at lands and stepping back to .040 off with groups of 5. The test showed some nice groups at the lands, .010 off and .030 off. I re tested these three seating depths then selected the load at the lands since it still fit in the AICS mag and gave the best accuracy. Now I took some of these rounds and loaded them with Wolf LR primers whereas I was using FGMM LR primers. Long story short, I gained 20 fps but accuracy went to shit - I shot four, 5 round groups, best accuracy just under 1 MOA.

I attached a pic of a target, 2 5-shot groups shot at 100 yards indoors, no wind. Whats with the weird horizontal stringing??? Everything is torqued to spec, rings are tight, etc. These groups were shot off a lead sled (have an injured rotator cuff I'm nursing at the moment) but I normally shoot bipod and rear bag.

Should I start the whole process over, go back to a certain point, go back to the FGMM primers (accuracy wasn't great with these hence the reason for trying the wolf primers, but it still wasn't as bad as the accuracy seen below), try different primers?

I'm loading with on a Dillon 550, Redding Comp seating die, body diving die, and Lee collet neck die - runout is measuring around .003.

 

[Eznutz]

What was your twist rate for the Krieger? I'm not an expert but i thought you might need a 1 in 10 twist for that heavy of a bullet. I'm not an expert by any means but that would be my initial guess.

 

[EXSOCAL]

1-11.25" twist - The Krieger I took off was only 1-11", not much difference.

 

[Temp9]

I attached a pic of a target, 2 5-shot groups shot at 100 yards indoors, no wind. Whats with the weird horizontal stringing??? Everything is torqued to spec, rings are tight, etc. These groups were shot off a lead sled (have an injured rotator cuff I'm nursing at the moment) but I normally shoot bipod and rear bag.

I'll venture a guess and say there's your problem. The Lead Sleds provide an inconsistent recoil surface leading to increased group size and stringing. I've never seen a Sled allow a gun to shoot what most of us would consider acceptable. Once you're back on a bipod and rear bag, I bet your groups drop back down to normal.

But I've been wrong before....

 

[JW21]

Are you putting a crimp on your loads? Variance in the crimp will give off different pressure levels. Im sure you know that but im just taken a crack

 

[EXSOCAL]

I'll venture a guess and say there's your problem. The Lead Sleds provide an inconsistent recoil surface leading to increased group size and stringing. I've never seen a Sled allow a gun to shoot what most of us would consider acceptable. Once you're back on a bipod and rear bag, I bet your groups drop back down to normal.

But I've been wrong before....

I was thinking the same thing, I was gonna call my buddy up to have him put some rounds through it off the bipod and see how that works.

Are you putting a crimp on your loads? Variance in the crimp will give off different pressure levels. Im sure you know that but im just taken a crack

No crimp, neck sizing with redding comp. bushing die and body die in separate operations.

 

[Pinecone]

43.8 sounds high with Lapua brass.

I am at 43.5 and Dan normally sees Lapua brass at about 43.1.

You might be near the edge of the node and that extra 20 fps is causing trouble.

But first, if you have any more Fed primers, load up a few rounds and test with the Wolf, shooting a round robin. This also checks the original load on the sled.

 

[oldno7]

I have a similar problem with a 700Remington chambered in 300 Wthby.
I was getting great groups for vertical, the horizontal sucked.

I just shot 7 different 3 round groups.
Each of the 7 groups, I changed OAL by .01.
At a shooting distance of 200yds there was a difference.
I found a length that was a better performer, in my gun.
might be an option?

 

[rduckwor]

I see two potential issues:
1. Lead Sled - Floppy mount with lots of play.

2. Primer Change - What primer were you using when you got good accuracy? If you're settled on Wolfe, you need to re-run the OCW. Really, A minor OCW in my mind - maybe starting around 43-43.1 GR Varget. Get your buddy to shoot it for you if he has the chops.

Good Luck,

RMD

 

[EXSOCAL]

43.8 sounds high with Lapua brass.

I am at 43.5 and Dan normally sees Lapua brass at about 43.1.

You might be near the edge of the node and that extra 20 fps is causing trouble.

But first, if you have any more Fed primers, load up a few rounds and test with the Wolf, shooting a round robin. This also checks the original load on the sled.

My old load was up at 44.6 gr Varget and I don't get pressure with this barrel until nearly 46 gr, I had a higher node up around 45.0 grains but I was already getting sufficient velocity from the lower node at 43.8 gr (2710 fps avg 20-shots). I am pretty confident in the 43.8 node as I mentioned, I ran 2 identical OCW tests on separate days because I was unsure about the first one, they both conclusively showed the same thing.

I have a similar problem with a 700Remington chambered in 300 Wthby.
I was getting great groups for vertical, the horizontal sucked.

I just shot 7 different 3 round groups.
Each of the 7 groups, I changed OAL by .01.
At a shooting distance of 200yds there was a difference.
I found a length that was a better performer, in my gun.
might be an option?

I shot a seating depth test from seated at the lands to .040 off in .005 increments, best accuracy found at the lands which is where I have been loading since that test. I never loaded SMK's at the lands which is why this was strange to me, all of my other loads found a home at close to .020 off…. maybe I should revisit this.

I see two potential issues:
1. Lead Sled - Floppy mount with lots of play.

2. Primer Change - What primer were you using when you got good accuracy? If you're settled on Wolfe, you need to re-run the OCW. Really, A minor OCW in my mind - maybe starting around 43-43.1 GR Varget. Get your buddy to shoot it for you if he has the chops.

Good Luck,

RMD

Agreed, lead sled sucks! It was my first time using one in my whole life and it will be the last…


Last time I did an OCW test I ran the OCW first, ran a follow up OCW with finer grain increments around the area of the node I found in the first test, then I did a seating depth test and last I took that recipe and loaded it with 3 different primers, wolf, CCI BR's. and FGMM…. The strange thing about this was all the loads shot extremely well, all sub .5 MOA, no flyers, no weirdness…. I just picked wolf primers for the old load because I have so many. This time is completely different, the primers I did the OCW with were FGMM, the accuracy was so-so… averages .6-.9" 5-shot groups at 100yds, now with the Wolf primers I get this weird horizontal like I'm shooting in 20 mph wind.

I'm guessing it has to be the sled….

 

[JW21]

I agree with rduckwor, have a buddy shoot it and see if that changes anything. To many variables with those led sleds and from what ive read they can have a impact of the barrel harmonics enough to change the poi slightly

 

[High Binder]

These groups were shot off a lead sled

Heal up and ditch the sled, problem solved.

 

[Dan Newberry]

I think it may be the sled also... I've seen a lot of people use those, never with good accuracy results.

When you get a chance to test again, see what 43.1 and 43.2 grains looks like, just out of curiosity.

The accuracy nodes normally run about 3% apart... but I'd also be curious to see how 43.1 grains works. That's a little lower than 3% under your last OCW node, but it is where many folks find good results with Lapua brass and 175's and Varget. 43.5 grains works good with Winchester brass with 175's.

If you're really on a good node, the primer shouldn't make a huge difference... a little difference, yes... but not a "deal killing" difference.

Dan

 

[Pinecone]

If there is a node at 45, the next lower node should be around 43.6 (3% lower). So close to your 43.8, but , the 43.8 might be close to the edge of the node.

Man, I would love to be seeing 2700 out of a 43.x grain node. I am getting 2600 out of 43.5 in Lapua brass.

 

[EXSOCAL]

I think it may be the sled also... I've seen a lot of people use those, never with good accuracy results.

When you get a chance to test again, see what 43.1 and 43.2 grains looks like, just out of curiosity.

The accuracy nodes normally run about 3% apart... but I'd also be curious to see how 43.1 grains works. That's a little lower than 3% under your last OCW node, but it is where many folks find good results with Lapua brass and 175's and Varget. 43.5 grains works good with Winchester brass with 175's.

If you're really on a good node, the primer shouldn't make a huge difference... a little difference, yes... but not a "deal killing" difference.

Dan

I'm gonna run another OCW this week from 42.6 - 45 and and see how it looks, without the sled of course.

If there is a node at 45, the next lower node should be around 43.6 (3% lower). So close to your 43.8, but , the 43.8 might be close to the edge of the node.

Man, I would love to be seeing 2700 out of a 43.x grain node. I am getting 2600 out of 43.5 in Lapua brass.

I saw a pretty definitive node from 43.4 - 44.2 which is why I went with the middle ground or 43.8. I cannot complain about the velocity though, this 26" Bartlein 5R is a getting 50 FPS more than my 24" Krieger was getting with almost a full grain more powder.

 

[Infinity]

43.8 sounds high with Lapua brass.

I am at 43.5 and Dan normally sees Lapua brass at about 43.1.

You might be near the edge of the node and that extra 20 fps is causing trouble.

But first, if you have any more Fed primers, load up a few rounds and test with the Wolf, shooting a round robin. This also checks the original load on the sled.

I'm at 45.1 grains Varget, new Lapua brass, F210M primers and 178 Amax bullets.