Long range load development at 100 yards.

[DHuffman]

You're correct in that there was no 51.3 test charge. I think any reference to that weight was an assumption that it might be a good one based on what 51.2 and 51.4 showed.
Again, though, started getting increasingly hard bolt lifts beyond about test #6 (50.8+)...

That was my assumptionon 51.3

I did however miss the "bolt lift" above 50.8 so would not look up there

 

[Rogmay]

I would try 49.1-49.7 in .2 gr increments and also 50.2-50.8, don’t get caught up in the needing velocity crap, test those an I’d bet you find a good node. Then test seating depths.

 

[JordanC.eth]

Hi everyone,

New member here. Building a new load and trying Erik’s method. After shooting 1 of each charge to check for overpressure, I shot 3 round groups with 0.5 gn increments from 40.5-43.0gn and wanted to get your feedback on node location. Would you all agree with 41.5, 42.0, 42.5 being the node? I ask because 41.0 is also tight, along with 42.5. However, they all appear to be at different locations vertically. Just want to make sure I’m analyzing this correctly, so any feedback is greatly appreciated. Should I shoot 5 shot groups instead?

6.5 CM Unfired Lapua Brass
H4350
GM210M
ELD-M 140gn

100yards

41.0gn - 2721, 2720, 2713, 2717 fps

41.5gn - 2752, 2740, 2753, 2742 fps

42.0gn - 2795, 2780, 2781, 2777 fps

42.5gn - 2833, 2833, 2840, 2844 fps

 

[AR Shooter]

Just me, but they all look like they would work. As in, I do not see a node. Again, if were me, would do the test again at 200yd (or longer).

 

[dstoenner]

41.0 and 42.5 look like nodes with an SD of around 2 for each. But they don’t look very wide. That is the throuble with such big jumps. .2 would be a better choice

David

 

[Jet]

Recommend you retest in .2 or .3 increments. Your .5 separation will skip right over a node. Based on your initial test I would retest between 40.8 - 42.6. The vertical in most of the groups is trying to tell you something. Reducing to .2 or .3 increments will give you more data.

How are you shooting the rifle? Prone off a bipod, bench of a rest? Please provide a bit more of your rifle and set up.

Thanks and good shooting.

 

[JordanC.eth]

Recommend you retest in .02 or .03 increments. Your .05 separation will skip right over a node. Base on your initial test I would retest between 40.8 - 42.6. The vertical in most of the groups is trying to tell you something. Reducing to .02 or .03 increments will give you more data.

How are you shooting the rifle? Prone off a bipod, bench of a rest? Please provide a bit more of your rifle and set up.

Thanks and good shooting.

Thanks for the additional feedback. Shooting a RPR with Leupold Mk V and using a lead sled on a bench. Do you think 3 shot groups will give enough data on a retest or should I switch to 5 shots? Really want to get this load dialed and not cut any corners, so I may just do that to be safe.

 

[Jet]

No need for 5 shot groups. Redo your ladder with 3 shot groups then do a seating depth test.

What is the purpose of the rifle. PRS/NRL, hunting (if so distance), recreation, etc.

No need for that lead sled unless it is required due to recoil sensitivity, handicap, etc. Recommend you test with it the way you plan to shoot it once it's tuned.

 

[Jet]

I fixed a typo above. Test with a separation of .2 - .3 not .02 - .03 like I stated earlier. Thanks @newbieshooter

 

[JordanC.eth]

No need for 5 shot groups. Redo your ladder with 3 shot groups then do a seating depth test.

What is the purpose of the rifle. PRS/NRL, hunting (if so distance), recreation, etc.

No need for that lead sled unless it is required due to recoil sensitivity, handicap, etc. Recommend you test with it the way you plan to shoot it once it's tuned.

Copy on the groups and lead sled. Truly appreciate the input. Rifle is being used for 1,000 yd IBS.

 

[JordanC.eth]

I fixed a typo above. Test with a separation of .2 - .3 not .02 - .03 like I stated earlier. Thanks @newbieshooter

All good. I’ll give you guys an update in the next few days.

 

[Cheese0570]

I have read through most of this thread. But trying to make sense of my own loads now. This is a 6-284 shooting 87vmax lapua brass federal magnum primers h1000 all loaded to the same load length. 60.8gr shoots good but consistently has high ES and SD. 60.2 and 60.5gr both have lower ES and SD but groups open up. Should I try to dial them in with the load length?

 

[Jet]

Don't worry about the ES/SD. Is the 60.8 in the middle of a node? If so, do a seating depth test. If not, go back and read the steps, shoot another ladder, find the middle of a node then do a seating depth test at that charge weight.

You already have an idea on what the velocities are so the next time you go to the range leave the chrono at home. Let the target tell you what shoots well.

Good Shooting

Rich

 

[Cheese0570]

Don't worry about the ES/SD. Is the 60.8 in the middle of a node? If so, do a seating depth test. If not, go back and read the steps, shoot another ladder, find the middle of a node then do a seating depth test at that charge weight.

You already have an idea on what the velocities are so the next time you go to the range leave the chrono at home. Let the target tell you what shoots well.

Good Shooting

Rich

I'm not sure it seems like it is. But I'm still trying to learn. I started showing pressure at 61.5gr. The first time out 60.5, 60.8, 61.1 all shot decently well. 60.8 was the best group but the highest Es/Sd all them were seated 0.035" off the lands @ 2.255". The picture is the group from tonight.

I also shot a load length ladder @ 60.8. Not sure I'm doing the right thing yet.

 

[heliryan21]

Thoughts on nodes?
IMR 4064
Sig Brass
WLR Primers
T3X CTR .308

 

[Capt. Oblivious]

Id scratch around between 44.2 and 44.5 on the top row

 

[Beiruty]

155/44.2 and adjust seating depth.
OBT5 is at 155/44gr

 

[heliryan21]

155/44.2 and adjust seating depth.
OBT5 is at 155/44gr
View attachment 1383251

Thanks, my thoughts exactly. What do you think for the 168? I’m thinking of a split between 42.9 & 43.2.

I was hoping the SMK 175 would have looked a bit better, I’ll have to redo that one and try again.

 

[Beiruty]

168 SMK OCW node is at 42.3gr
43.2gr is very promising (horizontal string) if there is no pressure signs.
41.7gr looks very good too.

 

[longrangewannabe]

Would it be safe to say 78.5-79.0 is a node? 79.5 averaged vertically isn't too far off either just opened up more horizontally. Going to shoot 81.0 and 81.5 tomorrow as there was no signs of pressure at 80.5