338 LAI & Bergers "Need Advice"

[SHRTSHTR]

Hi,

I have a 338 LAI and am currently shooting 300gn SMK"s. I have a killer load worked up with the SMK"s but have not had good luck with the new Bergers.

We have run well over a 100 rounds down range with the Gen II's and have not been able to work up a good load at distance. I currently run 100gns of Retumbo .015 off the lands for the SMK's. I started about 99gns Retumbo and thought I had a good load worked up for the Bergers at closer ranges but did not do so well at distance.

I have tried seating depths from .020 off the lands to touching. I also tried H1000 w/ CCI-250's. This load looked promising but would open up at distance and could not get very good velocities without seeing some slight pressure signs.

Would like to start over this winter with load development and see if I can get the Bergers to shoot. Looking for some advise on where I might start again. I have about 650 of the new Bergers sitting here.

I might ad that the Bergers seem to shoot 1 moa flatter than the SMK's with the same 300 yard zero at a 1000 yards. I might have had a good load but think I may have relied on my Oehler 35 to much during load development. Was looking for the lowest ES instead of shooting further out. Most of my testing was at 100-300 yards.

I am sure I left something out here but will answer questions if I get any. Thanks in advance.

 

[jmden]

Hmmm...that's got to be frustrating. Just for comparison, not that it'll make a difference, but my load it 101g Retumbo with F215M. Best I can figure is that I'm about .010 off the lands using Sinclair's tool for this.

Kirby was surprised at the 101g load until I mentioned that I was using a match primer, which he doesn't like so much for these big magnums. Says they typically don't burn as hot as the regular primer and that's likely why I've got a 101g load doing what 100g usually does for him--2976 MV out of a 29" barrel.

That's right close to the 'sweet spot' of 2950-2975fps where Kirby says he usually finds his best accuracy with a 28-30" barrel. This load is doing very well at long distance. No so happy close up--just under 1 MOA is the norm 100-200 yds, but seems to hold to 1/2 MOA in good conditions and me shooting well out to 1K yds.

 

[SHRTSHTR]

jmden,

I just looked at my load data using Retumbo and 300gn Bergers. I was getting 2,958fps with a 100gn Retumbo .010 off lands and Fed 215 magnums. My ES was 10 with an SD of 5. This was a 6 shot group, cooling in between.

My rifle description: McMillan A-5, Stiller TAC-338 action, Jewell trigger, Seekins bottom metal, 30" Lilja #8 contour, 10 twist and muzzle brake. NF 5.5x22x56 NPR2, 40 moa rail.

The load data above looks good reading about it but not so good on paper. I must admit that while testing I had wind but under 10mph. My vertical spread at 1k was just under 2.5 inches. My horizontal was 9 inches. Funny thing is after studying my targets a closer ranges, I seem to always get one flyer with the Bergers.

Based on the info you provided, I think I am close to where I should be. Would like to try some more load development but do not want to waste precious barrel life. I have about 400 rounds down the tube now.

 

[sp6x6]

Did I read it right, you had 9'' horizontal, with up to 10 mph wind? That could account for that spread. Mine is a Norma, similar, 300 .005 off, F215,87.5 Retumbo 2725 vel. 6'' is my best @1000, but not alot on paper there yet. Half a dozen groups 2'' and under, 1 1/8'' best @ 400. Although lots are 2 touch or close and one out more. Have shot some triangle shape too. gen 2's

 

[SHRTSHTR]

sp6x6,

Yes I had 9 inches horizontal spread. I realize that is a pretty good group at 1k. I should clarify things a little. I seem to get one flyer out of a 3 shot group at pretty much any distance using the Bergers.

I very rarily get flyers with the smk's. When I do, I figure it is wind. Just wondering if it is something I am doing wrong with the Bergers? I really want to make these work in my rifle. I have followed pretty much every thread here about the 300gn Bergers. I would like to get the same results as others have. Of course most of my reading has been about the Edge and 338 LM. Not a whole lot of info on the faster 338's that I have seen.

Seems I need to burn some more barrel and find a load or do my test again and see what I get.

 

[Broz]

Ray, I do not have the answer to your problem. But if it were me starting where you left off and using your previous data, and what I like to do. I would start with a load of H-1000 and seat them .040" off the lands and see if it gives you a direction. There is a possibility your rifle might like a little jump with these bullets.

Just a thought.

Jeff

 

[SHRTSHTR]

Jeff,

I appreciate your response. I will give it a try, I am at a loss right now. I need to find a way to eliminate the flier. If I can accomplish that I will have a winner!

 

[Broz]

Jeff,

I appreciate your response. I will give it a try, I am at a loss right now. I need to find a way to eliminate the flier. If I can accomplish that I will have a winner!

Chamber heat ???? and RETUMMMMMMBO???? maybe???

Jeff

 

[SHRTSHTR]

Jeff,

I know how you feel about Retumbo. During my load development with the Bergers H1000 was where I spent most of my time. H1000 showed real promise and gave me better velocities than Retumbo.

Higher velocities with H1000 might be part of my problem. I really liked the extra velocity but don't think the rifle did. 100gn H1000 yielded 2,985 fps, ES 14. I shot a 3 shot group at 1k with this load. I got a little over 1 moa on this day.

My sweet spot with smk's is around 2,955ish. Going to try backing down a little with H1000 and see if that makes a difference.

From what I have read, Retumbo in the 338 Improved versions seems to be the powder. Kinda like how H1000 is the go to powder in the 338LM and Edges.

This is why I came here looking for some guidance. Like you the smk's shoot great for me. I stuck with the smk's this hunting season. 5 Antelope and 1 cow elk. Nothing was shot under 800 yards and the furthest was 955 yards. All 1 shot kills. Not trying to brag but I would like the best of both worlds.

I know, I know, if it ain't broke why fix it? I want that extra edge that I am sure Bergers will give me. Even if it costs me a barrel to get there. gun)

 

[Autorotate]

Mr. Ray-

Your pursuit of perfection/excellence is commendable gun)

To add what Jeff said (even though I'm a Retumbo guy, that might be worth looking at. Load 6 rounds. Put three on truck defroster, top of the truck radiator (that's me, not saying that's smart for everyone ), someplace where'd they'd warm up. Let the other three sit out overnight, or in the back of the truck on the way to the range. See what Mr. Oehler says. I don't have my rifle logs to post, but I found different lots of Retumbo and H1000 to act differently. H1000 is still one of the most temp tolerant powders I've seen though.

I don't like any less than .004 total/.002 radial neck clearance in my 30-338 and 338 LMAI anymore. I'd get a flyer on both the target and on the chrono like you speak of when it was less than that.

And I know Lilja makes some shooter barrels, but I think you and Jeff listened to me whine some about beating my head against the wall trying to get a Norma/Lilja to shoot some Gen 1 Bergers. Still got a bunch of them things. They shoot great out of the Brux 9.8 twist as fireform loads in the 338 LMAI in the 2800-2820 range. But they don't make the trip very well in loaded up formed cases

So in the end I'd check-

1. +1 on the temp tolerance of your powder/powder lot
2. check for a minimum of .004 total/.002 radial nk clearance
3. shoot some "blind" groups, where you don't know which one your shooting SMKs or Bergers

 

[SHRTSHTR]

Thanks Tim,

Sorry for the late reply, I wanted to check my cases. A loaded case measures .366 and my chamber is .3705 I have the .004 clearence . I have been wanting to see how temps effect my velocities and plan on shooting this weekend. I will see how it goes.

I had 250 of the Gen I Bergers but returned them and bought 750 of the new ones. I will get it figured out and really appreciate the level of advise I got on this thread.

I have a late season plains Elk hunt next week. Looking to stretch the 338LAI out a little further on this hunt. I will have a lot of free time to get the Bergers going this winter. Thanks guys, Ray

 

[Topshot]

SHRTSHTR,

I have had similar results to you at long range.
In my opinion, the 300gn Berger needs a barrel twist faster than 1 : 10.

 

[Broz]

SHRTSHTR,

I have had similar results to you at long range.
In my opinion, the 300gn Berger needs a barrel twist faster than 1 : 10.

If this is true I think you would have to look deeper than twist. They shoot great out of my 1 in 10 6 land lilja in my 338 LM. I have 300 down range and have group tested them on paper to well past a mile, and everywhere in between.

When I say look deeper it would be barrel manufactures, inner tube dimentions , rifling design and number of lands.

Jeff

 

[jmden]

SHRTSHTR,

I have had similar results to you at long range.
In my opinion, the 300gn Berger needs a barrel twist faster than 1 : 10.

They seem to do fine out my Rock 1:10.