Why Do The Tightest Groups Always Have The Worst SD/ES?
- Thread starter sig2009
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Find your best SD/EDs first then play with seating depth to get groups. Don't even look at groups until you get you SD/EDs down. May be a good group at 100 but an extreme spread won't hold a decent group at 1000.
I heard him state the opposite.
Not sure if you saw my edit but it's at 6:30.
But he states your issue is combustion. Change powder, primer, or neck tension. Any combo or all three.
Honestly, I shoot factory ammo almost exclusively now (6.5CM). Too much work to reload for my needs. If I found it less tedious, I might continue. Results were good, just tedious. Maybe look into Prime. You can't reload for their price unless you load A LOT of rounds over a long time. IMO.
I know. Unfortunately I have tried H4350,RL16,IMR4451,RL17 with less than good results. I use GMM primers and Redding Bushing dies now. Problem is by the time you eventually find something that will shoot it's time to change your barrel so I'll, probably stick to .308 and ditch the 6.5.
How far are you planning on shooting?
What exactly are the components you are using? Large rifle magnum primers, small magnum primers, large standard primers, small standard primers, what brass brand, how many times reloaded, do you anneal, how often do you anneal, what is your variation on seating depth and shoulder bump? Basically what in detail is you process?
Sorry to have so many questions but I haven’t seen some of these answered?
Maybe your barrel is your problem. I had a relatively easy time for finding a load that worked for me.
10.4 SD
37 ES
Not great but workable.
Also, have you tried taking your best load/group to distance/your target distance?
What are your es/sd numbers?
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It means that you have the proper node. It means you can have the widest deviation and yet still stay within that accuracy node. Don't question it, just shoot it.
This is what I shot today with 2 different powders H4350 and IMR 4451.. Seating depth from .025 off lands to .120 off lands. GMM primers. Shoulders bumped .002. Annealed. FL sized with Redding neck bushing sizing die .286., so >002 neck tension. Hornady brass. Necks turned. 140gn Nosler RDF. Testing at 100 yds but can go out to either 300,600 or 1000 yds.
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Are you using gmm standard, magnum, small or large?
How is it when seating? Is it smooth or does it feel like there is a hard spot? Are you sure your 41.0 grains is what it likes? What got you to your 41.0 grains? Is this a custom gun? What barrel/gun brand?
You’re misinterpreting several things.
1: Erik runs chrono first without shooting groups and then goes into seating depth (I’ve been to his class)
2: The video you linked, he is shooting a current barrel with a known load. He’s fine tuning for an F class match out of his normal area. Again, for an F class match. He could easily take something performing like that to a practical match. If you’re not shooting a game where you need to be inside an moa at 1k at all times, there is zero need to fine tune like he is doing. You won’t be able to shoot the difference without a front rest and rear bag like he’s using.
3: If you can’t dial in good groups with seating depth, his tuner won’t help.
4: Your data suggesting good groups = bad ES is likely just a product of statistical variance or from not continuing load development properly. You can literally take any charge weight and make it shoot via seating depth. Doesn’t matter the ES.
Your issue is either:
1: shooter inconsistency
2: improper load development process
3: bad components
4: bad barrel
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Also, I see you’re using Nosler bullets. Use Berger. This fixes many, many issues I see with load development.
Use Berger bullets and lapua (or equivalent) brass. Be meticulous in your brass prep and throw powder to a kernel. After that, it will be hard to have a bad load.
Use Berger bullets and lapua (or equivalent) brass. Be meticulous in your brass prep and throw powder to a kernel. After that, it will be hard to have a bad load.
Did everyone else not notice this poor bastard has to say "freedom seeds" instead of bullets and "freedom delivery device" instead of gun so he does not get fucked by fucktube? This country is going down the shitter. The first thing he says is get the es right. Then the second thing he says is get your groups tight with seating depth. And the third thing was if the first 2 are good and your groups go to shit at distance its your freedom seeds. As far as pulling the barrel I think he meant if his barrel gets to 1/2moa its toast and time for a new one.
Also as always, context. He’s pulling barrels that that don’t shoot 1/4” on his F class rig. As that’s completely different game than most on the hide play.
. "You can literally take any charge weight and make it shoot via seating depth. Doesn’t matter the ES."
As you can see by the results I had today this didn't work but wanted to try it anyway. Beginning to think that this Patriot Valley Arms 26" barrel is a dud. All my .308 bolt guns put this 6.5 to shame accuracy wise.
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I’m assuming (didn’t see it, but might have missed it), you’re shooting these with a Labradar?
Are you shooting the groups on paper separately from the chrono groups??
In addition to the above recommendations and just because I didn’t see them...to start, how does your rig shoot factory ammo?
1) If your rig won’t shoot a factory match 6.5 round, is your scope, barrel, etc all tight? (I’m asking because I’ve witnessed this at the range where equipment was the culprit and not the hand loads)
2) Is the Hornady brass 1x fired or new brass? I’ve had Hornady brass that that came from 2 very different lots with a large variation in case capacity. After I realized this I just sorted them and SD/ES fell in line. That said the recommendation above to move to Lapua or similar will take brass out of the equation.
1) If your rig won’t shoot a factory match 6.5 round, is your scope, barrel, etc all tight? (I’m asking because I’ve witnessed this at the range where equipment was the culprit and not the hand loads)
2) Is the Hornady brass 1x fired or new brass? I’ve had Hornady brass that that came from 2 very different lots with a large variation in case capacity. After I realized this I just sorted them and SD/ES fell in line. That said the recommendation above to move to Lapua or similar will take brass out of the equation.
Don't know if this applies to the situation but, a few years back, I nearly tossed a barrel that ended up being a spectacular shooter. The reason was, I was shooting back to back groups with different powders. By luck, while testing seating depth, I had 3 groups of varying seat depths (one type of powder) and one group really shined. Having gotten frustrated with this barrel, I decided to just run the same test again and got the same results to a tee. In retrospect, I got lucky but I learned from that. Changing bullet or powder group to group will skew your results.
I now test 1 type bullet and 1 type powder in 5 round groups. I only vary powder charge to find a velocity I can live with and good SD/ES. I then test seat depth for best group. If this fails, I'll thoroughly clean the barrel and then change powder OR bullet and repeat. Using this method has enabled me to normally get a load dialed within 45-60 rounds; often less. I begin load development on a new barrel right from the start. Even though barrels change a bit in the first 100-200 rounds, I at least become confident of the bullet and powder it seems to prefer and only need a little tweaking as the barrel wears.
After a great deal of experimenting with the 6.5 CM, I've settled on 3 bullet types and 3 powder types and could really knock each of those down to 2. Many of my barrels have been easy to load for but the same method works for more finicky barrels too. After watching several EC videos, I found his way is very similar to what I stumbled upon. BTW, the RDF is NOT one of those 3 bullet types - at least not for me.
I now test 1 type bullet and 1 type powder in 5 round groups. I only vary powder charge to find a velocity I can live with and good SD/ES. I then test seat depth for best group. If this fails, I'll thoroughly clean the barrel and then change powder OR bullet and repeat. Using this method has enabled me to normally get a load dialed within 45-60 rounds; often less. I begin load development on a new barrel right from the start. Even though barrels change a bit in the first 100-200 rounds, I at least become confident of the bullet and powder it seems to prefer and only need a little tweaking as the barrel wears.
After a great deal of experimenting with the 6.5 CM, I've settled on 3 bullet types and 3 powder types and could really knock each of those down to 2. Many of my barrels have been easy to load for but the same method works for more finicky barrels too. After watching several EC videos, I found his way is very similar to what I stumbled upon. BTW, the RDF is NOT one of those 3 bullet types - at least not for me.
Then your groups literally mean nothing. The magneto is a weight on the end of your barrel that will move around during recoil.
You’re shooting Hornady brass and Nosler RDFs. I’d start with those two deficiencies before writing off a barrel.
Edit: and don’t shoot for group size with something hanging off your barrel.
This is your answer, period end of story. If you are shooting with anything on the barrel it is going to effect harmonics, take the magnospeed off and work your loads up again.
Dthomas is right. Find your charge weight with magnetospeed, take the thing off then run seating depth test. The seating depth test you did goes out the window. if that isnt it, you need to toss the noslers. the hornady brass will still produce great groups as long as the brass prep is there. It definitely isn't the barrel. I have no less than 10 PVA barrels right now and i haven't had 1 that wasnt a shooter. i was at PVA this weekend getting barrels spun. Its not the barrel. The good news is, your seating depth was probably in the test you did, you just tainted the test with the chrono on the barrel
