Help me troubleshoot issue with ELR load please

[DTF370]

Hey guys,

I am loading my 338 Lapua Improved. I am trying to get my SD under 10 fps, but so far I’ve not been very successful. I can absolutely get 1/4 minute loads but nothing I do will get me inside of that 10 fps SD. With this being an ELR rig, I feel like that is a must. Will somebody help me troubleshoot? My setup/process to follow:

Setup:
26” K&P/LRI barreled Ruger RPR
338 Lapua Ackley Improved
Lapua Brass (fully fireformed)
Fed 215M
Powders: Retumbo, N570
Bullets: 250/300gr elite hunter, 300g A Tip, 285 ELDm
Hornady bushing die based on reamer print

Process:
1) Torch anneal
2) Vibratory tumbler
3) Size (bump shoulder .02) .02 neck tension
4) Trim/chamfer/debur (generally not necessary) all cases within .002
5) Frankfort premium primer seat to same depth Federal 215m
6) HBN coat bullets, bore, and case neck
7) powder to a .02 grain resolution
8) hornady micrometer seater with appropriate seating stem
9) confirm base to ogive length

300 A-Tip/ 98gr N570/215M (2850fps)and 285 ELD/ 99gr N570/ 215M (2900fps) will net 1/4-1/3 MOA. This is on the edge of pressure signs. Best I have been able to get is roughly 20SD.

I’ve tested other powder/bullet combos with similar SD results.

Any suggestions on where to start?

 

[memilanuk]

Change powder or primer is usually the easiest solution.

Other possibilities include the mechanical parts of the ignition system - crap in the area around the firing pin, firing pin spring needing replaced, etc.

 

[DTF370]

Change powder or primer is usually the easiest solution.

Other possibilities include the mechanical parts of the ignition system - crap in the area around the firing pin, firing pin spring needing replaced, etc.

I do have like 30 CCI mag primers, I could give that a try. I think I’m out of powder choices though. Atleast staying inside of temp stable powders. I have a ton of H1000 but it’s a little fast for this cartridge/bullet.

 

[memilanuk]

I'm not at all familiar with the RPR fire control system, so I can't help with specifics there. But I have seen people chase their tails at the reloading bench when the issue was really excess oil/grease or grime on the firing pin assembly causing inconsistent ignition. That sort of thing can absolutely give you tight groups at short range, but leave you pulling your hair out fighting vertical stringing at distance.

 

[CoryT]

First question, how are you measuring the velocity? An expander mandrel may provide better neck diameter than the bushing die due to case neck thickness. Max pressue loads don't often produce the most consistent velocity, consider going down to the next accuracy node. What's the bullet jump distance?

 

[918v]

Hey guys,

I am loading my 338 Lapua Improved. I am trying to get my SD under 10 fps, but so far I’ve not been very successful. I can absolutely get 1/4 minute loads but nothing I do will get me inside of that 10 fps SD. With this being an ELR rig, I feel like that is a must. Will somebody help me troubleshoot? My setup/process to follow:

Setup:
26” K&P/LRI barreled Ruger RPR
338 Lapua Ackley Improved
Lapua Brass (fully fireformed)
Fed 215M
Powders: Retumbo, N570
Bullets: 250/300gr elite hunter, 300g A Tip, 285 ELDm
Hornady bushing die based on reamer print

Process:
1) Torch anneal
2) Vibratory tumbler
3) Size (bump shoulder .02) .02 neck tension
4) Trim/chamfer/debur (generally not necessary) all cases within .002
5) Frankfort premium primer seat to same depth Federal 215m
6) HBN coat bullets, bore, and case neck
7) powder to a .02 grain resolution
8) hornady micrometer seater with appropriate seating stem
9) confirm base to ogive length

300 A-Tip/ 98gr N570/215M (2850fps)and 285 ELD/ 99gr N570/ 215M (2900fps) will net 1/4-1/3 MOA. This is on the edge of pressure signs. Best I have been able to get is roughly 20SD.

I’ve tested other powder/bullet combos with similar SD results.

Any suggestions on where to start?

Skip annealing

 

[whatsupdoc]

Stop the torch anneal, clean the firing pin and the inside of bolt.
How are you resizing the brass? How are you controlling the neck tension?
Stop the HBN coat bullets, bore, and case neck.

 

[Sig Marine]

What method did you use to determine your load?

 

[DTF370]

First question, how are you measuring the velocity? An expander mandrel may provide better neck diameter than the bushing die due to case neck thickness. Max pressue loads don't often produce the most consistent velocity, consider going down to the next accuracy node. What's the bullet jump distance?

I am measuring with a Caldwell premium g2 chrono. I have been able to shoot side by side with a Labradar. On the day I did that, it was reasonably accurate. Of course I know environment can change that day to day. I have considered a mandrel, that’s probably a decent place to start. With the A-Tip, I am jumping .05, and with the ELD, I am jumping .02 and this keeps me at mag length. I’m not opposed to single loading though.

Stop the torch anneal, clean the firing pin and the inside of bolt.
How are you resizing the brass? How are you controlling the neck tension?
Stop the HBN coat bullets, bore, and case neck.

I’m sizing with a full length hornady match die. I sent them my reamer print and had it made to my chamber’s specs. I’m controlling neck tension via bushing size. Any specific reason to stop HBN, or are you suggesting it to eliminate a variable? Not arguing with you or anything, I’m just curious if there’s info out there I’m not aware of is all.

What method did you use to determine your load?

After fireforming, I did a pressure and ladder test. Unfortunately this was only at 350. I picked my area of minimal vertical and then began OCW in the “flat spot”. After that time I gained a chrono. I did a smaller OCW and began playing with seating depth over the chrono, and that’s where I’m currently at. I might be the reason for the powder shortage, I have been here for a little bit now. Normally this only takes me 20-50 rounds and I can settle on something.

 

[CoryT]

Given the chrono, I'd just go to 1500 or so and test for vertical dispersion. The HBN coating is not going to help, and may hurt. Keeping the coating consistent is VERY hard. After annealing the case necks need to be well brushed to remove the rough tarnish that will develop. I do use the Imperial graphite neck lube sparingly, which seems to work fine for me/

 

[Dogtown]

This is the way

 

[Doom]

How many rounds is your SD based on?

 

[DTF370]

How many rounds is your SD based on?

For load development, just five rounds. An example of what I’m seeing is something like 2843, 2874, 2834, 2851, 2820. Velocity values don’t seem to have a pattern or consistency.

 

[Dogtown]

That’s totally normal. That’s the noise in the samples.

 

[Dogtown]

If your goal is to improve consistency in your loads, you have to increase the consistency in your components and process. Some things I’ve found over the years that help that:

• Shoulder bump
• Neck tension
• Powder charge
• Seating force and depth

It can sometimes be difficult to get all of your case dimensions identical, but you can size a bunch of brass and then sort them into groups with the same shoulder bump and shoot them together.

Neck tension is much easier to control with bushing dies and neck mandrels.

Powder charge consistency can be made more consistent with an old fashioned beam scale and lots of patience, or investing in a high quality scale. Most of the economical solutions just drift too much to make exacting loads.

Seating depth measurements tend to be more consistent with base-to-ogive comparators and quality calipers, as well as doing your due diligence in finding a seating depth during load development that performs well. And you’d be surprised how much consistent seating force helps too. You can go as fancy as an AMP press, or simple seating force arbor press, or just start lubing necks with Imperial Dry Neck Lube or Neolube.

None of the above is necessary to make good ammo, but all can help make more consistent ammo.

 

[Doom]

Five rounds for analyzing standard deviation is pretty much a waste of rounds. One round 2874, takes the SD from 13.2 to 20.1. To gain some certainty as to what your real standard deviation is likely to be you need between 20 and 30 rounds. The confidence interval for your 5 test rounds is from 12 to 58. Meaning if you were to shoot another 5 shot string there is a 95% chance it will be between those values.

 

[Baron23]

Maybe I missed it....but the OP said that his load shoots 1/4 MOA but doesn't indicate that his groups are opening up further at range. He also doesn't really say that the 1/4 MOA is just at 100 yards.

So, I guess my first thought is who cares what the SD is if the load shoots 1/4 MOA.

With that, I'll take my ELR-ignorant butt out of this thread! haha

 

[Dogtown]

The confidence interval for your 5 test rounds is from 12 to 58. Meaning if you were to shoot another 5 shot string there is a 95% chance it will be between those values.

It's nice to see someone else took Elementary Statistics in school too.

 

[secondofangle2]

I'd be really interested in the folks with the "single digit SDs" posting some screenshots of those with 20+ round strings. I wager it's selective memory of statistical noise most of the time

 

[DTF370]

Five rounds for analyzing standard deviation is pretty much a waste of rounds. One round 2874, takes the SD from 13.2 to 20.1. To gain some certainty as to what your real standard deviation is likely to be you need between 20 and 30 rounds. The confidence interval for your 5 test rounds is from 12 to 58. Meaning if you were to shoot another 5 shot string there is a 95% chance it will be between those values.

While I would totally agree that a five round test is useless when determining your true SD, but in my first five rounds, if I am in an unacceptable SD range already, wouldn’t shooting 20 rounds just be wasting components and barrel life? In my mind, testing velocity consistency over 20 rounds is something that should be done at the very end of load development when I believe I have a solid load, correct? Shooting that many rounds per charge weight, or seating depth range would result in the expenditure of a metric shit ton of components. To me it makes sense to test small batches until I find something that seems to show some promise. And then expand from there with testing more rounds. Please correct me if I’m wrong.

Maybe I missed it....but the OP said that his load shoots 1/4 MOA but doesn't indicate that his groups are opening up further at range. He also doesn't really say that the 1/4 MOA is just at 100 yards.

So, I guess my first thought is who cares what the SD is if the load shoots 1/4 MOA.

With that, I'll take my ELR-ignorant butt out of this thread! haha

My apologies, I probably should have included this. My initial load development testing is only within 200 yards as that’s what I have convenient for me. On my final phases of load development I move out to much longer distances. I am holding great groups, but these groups will have vertical stringing with the velocity spread that I have. Probably is not a huge issue inside of 1000, but I would assume SD of 20-40 will be pretty problematic beyond a mile.

 

[Dogtown]

but I would assume SD of 20-40 will be pretty problematic beyond a mile.

ES? SD of 20-40 would be....bonkers.

 

[918v]

Yes. But he said SD in his original post.

This is a telltale sign of brass too soft at the neck/shoulder, releasing the bullet incorrectly.

 

[secondofangle2]

what is the method of this "torch annealing"?

 

[secondofangle2]

seriously, I doubt the temperature is "given" or the period of time "specific" unless he's using an automated device (eg Giraud or Benchsource) and Tempilaq which he has not specified

 

[memilanuk]

Sorry, your question came across differently.

Personally I think there's plenty of things to check before dissecting his annealing process... But that's just me

 

[secondofangle2]

I run Giraud and AMP. I recently had 2 batches of 338 LM brass, one 1x fired and Giraud annealed (prior to AMP) and one AMP annealed and the seating force between the two was gigantic. My torch set-up for Giraud has always been on the "less is more" cautious end of the spectrum, and this experience taught me I was wrong to think that way.

 

[DeathBeforeDismount]

If your not going to use an AMP, then skip annealing. Its too much of a wildcard. I would start isolating issues and replacing questionable gear with quality gear.

Start with better dies. Since you are shooting 338AI, order a set of Widdens. Use a mandrel, Buy a FX120i and autotrickler/supertrickler. Invest in a henderson. Play around with mandrel size and bushing size until you can confidently control neck tension. Skip the HBN shit, the only lube you need is Lanolin. Anything frankfort arsenal goes in the trash can.

If you cannot make good ammo using good components and equipment, I can't really help you. The good stuff almost loads itself and the results show up on paper.

If you are already close to preassure, back way the fuck up. You are just asking for more problems.

 

[DTF370]

ES? SD of 20-40 would be....bonkers.

Yes SD, not ES. 40 may be an exaggeration but 20-25 has been pretty standard for development in this rifle. No question I can improve, I think we all could in some way. That’s exactly why I’m here, to learn! I guess what has me scratching my head more than anything is I have had no problem getting single digit SD’s with other rifles that I load for. My 6.5 SAUM is running about 7SD/17ES. I’m just left scratching my head.

Based upon what you guys have said I do think I have some easy areas to work on first. I’ll start by eliminating the simple variables and the others slowly. ELR is still new-ish to me. I do plan to invest in high end equipment, but it can’t happen all at once. Might as well learn in the meantime.

I tore down and cleaned my firing control group. It was a little grimey, but it wasn’t bad.

I’ll cut out HBN. I’ll reduce my load a decent amount and do a small pressure ladder to reconfirm my pressure limit.

I will swap primers and give CCI a go.

If this doesn’t improve, I’ll stop annealing, order a mandrel or additional bushings.

If this doesn’t work, I’ll start completely over with different equipment.

 

[Dogtown]

Some barrels are just outliers and don't shoot well at all or are super picky about what you feed it. You may have just gotten a dud. I ran into a similar problem way back when and the first thing I did was buy a box of factory ammo to see if it was just my handload-fu that was causing problems, but nope - it shot like shit too. Unfortunately in your case that's not much of an option since you're shooting a wildcat. And if your process is already turning out quality ammo for other cartridges and rifles, then that too may be evidence of a wonky barrel.

 

[Sig Marine]

I'd be really interested in the folks with the "single digit SDs" posting some screenshots of those with 20+ round strings. I wager it's selective memory of statistical noise most of the time

Your wish is my command…
Shot from my 300 Norma, NO culls; all shots recorded shooting 1860 to 2425 yards.

 

[DTF370]

Some barrels are just outliers and don't shoot well at all or are super picky about what you feed it. You may have just gotten a dud. I ran into a similar problem way back when and the first thing I did was buy a box of factory ammo to see if it was just my handload-fu that was causing problems, but nope - it shot like shit too. Unfortunately in your case that's not much of an option since you're shooting a wildcat. And if your process is already turning out quality ammo for other cartridges and rifles, then that too may be evidence of a wonky barrel.

I am most certainly not too proud to admit that I believe I have plenty of room for improvement and education. Plus higher end equipment to boot. I would place myself as a seasoned reloader, but I am light years away from being an expert. We shall see in regards to the barrel. I will be very surprised if it truly is a lemon. I just have not had issues like this before. I will apply some of the advice gained in this thread and see what happens!

 

[secondofangle2]

Your wish is my command…
Shot from my 300 Norma, NO culls; all shots recorded shooting 1860 to 2425 yards.
View attachment 8080688

that's pretty damn good. What powder/bullet?

 

[Sig Marine]

that's pretty damn good. What powder/bullet?

225 ELD-Ms over H1000. Bartlein barrel with 1:9 twist spun up by Greg Young, aka Bugholes.

 

[Doom]

Your wish is my command…
Shot from my 300 Norma, NO culls; all shots recorded shooting 1860 to 2425 yards.
View attachment 8080688

Your 95% Confidence interval is between 2924 and 2928 fps. You SD confidence interval is between 4 and 6.6 fps. I think you've got it!