Long range load development at 100 yards.

[TerryH]

Terry.... for my 2 cents... I'd check to see it .011 is repeatable...if not... then try 43.8 of powder... because the ones on both sides are on the same POI.... then... .014 seating depth because it's in the center of the other two that have the same POI... and or level point. The 011 looks great, but it's right on the edge of .008...not in the center... like 014.

Thanks for the advice Daniel.

 

[savageshooter86]

55.6, 55.7. Moving on to seating depth and try the BR2’s.
View attachment 1033297

to me that shows that 55.6 is are out of the node. Notice how 55.4 and 5 same POI and size pretty much. Then 55.6 dips down and opens up. I'd say area is 55.5 max and probably 55.1/2 start of it

 

[TerryH]

Apparently the work put in on OCW and seating was well worth it. Thanks to @Erik Cortina and all that have contributed to this thread!

 

[David Christian]

Greetings all,

I just came across this thread and ended up reading it start to finish. I happen to have just put together a new F-class gun and am mid stream in load development. I've already found an initial powder node (41.4 gr H4350) and went on to the bullet seating test today. Started with a -.010 jump, in .003 increments ending at a -.031 jump. I plan to go back to fine tuning the load in .1 or even .05 grain increments next. Thoughts on this set of groups?

 

[Bart B.]

I plan to go back to fine tuning the load in .1 or even .05 grain increments next.

I wouldn't increments smaller than 2/10ths grain. Unless you're willing to shoot 30 shot test groups.

 

[Erik Cortina]

Greetings all,

I just came across this thread and ended up reading it start to finish. I happen to have just put together a new F-class gun and am mid stream in load development. I've already found an initial powder node (41.4 gr H4350) and went on to the bullet seating test today. Started with a -.010 jump, in .003 increments ending at a -.031 jump. I plan to go back to fine tuning the load in .1 or even .05 grain increments next. Thoughts on this set of groups?

-0.025” seems happy.

 

[Erik Cortina]

Taking what I learned from this great post and putting it together with my rookie opinion, I would agree with you, increase your powder weight a little till your groups open back up then back off. After that fiddle with your seating depth to fine tune.

55.4
That’s where your ES is the lowest.
Then simply adjust seating depth.

 

[David Christian]

What should I see in these results? Post bullet seating test, here are the results from my powder fine tuning today.

I shot sighters then a string then let the barrel cool, two strings then cool, then another two strings then cool, etc. All cases were prepped the same, yet I do find it curious that my first round on each cool barrel string seems to have a much higher velocity than the rest within the same respective string. Am I reading too deep, or would those groups have had a tighter ES if the barrel was warmer from the start?

 

[savageshooter86]

What should I see in these results? Post bullet seating test, here are the results from my powder fine tuning today.

I shot sighters then a string then let the barrel cool, two strings then cool, then another two strings then cool, etc. All cases were prepped the same, yet I do find it curious that my first round on each cool barrel string seems to have a much higher velocity than the rest within the same respective string. Am I reading too deep, or would those groups have had a tighter ES if the barrel was warmer from the start?
View attachment 1039492
View attachment 1039493

I’d try 41.2

 

[Bart B.]

You may be shouldering the rifle different for each string's first shot.

Starting with a clean bore and two sighters, you should be able to shoot 30 to 40 shots once every 25 to 30 seconds keeping each round in the chamber for 15 seconds and have all leave in a small velocity spread. Short range groups can be 1/4 to1/3 MOA, long range 1/2 to 2/3 MOA; all 30 to 40 shots in that group.

If your shot impact starts moving from point of aim as barrel heats up, the barrel is either poorly stress relieved or fit to a receiver whose face isn't squared up to the barrel thread axis. This assumes your shooting position doesn't change across the string of fire.

 

[Nellej12]

In need of some advice.
I just shot these rounds yesterday at 100 yards, 32 degrees, 2 t0 4 mph wind. All round were seated 20 thousands off, Brass was all new.
rifle: 338 lapua, 300 grain bergers, Powder h-1000, barrel is 30 inch. Rounds shot off bi-pod and rear bag.

To me 88.5 (Block 6) looks really good but 89(block 7), 89.5(block 8) and 90(block 9) all look to line up pretty well. would you load up 90.5 and 91 to see if you reach any pressure signs.

Should I load some more rounds at 90.5, 91, 91.5 to see if I can find pressure?? Or run with one of these.

Powder range 86-90 grains.
1. 86gn - 2674, 2657, 2638 SD- 17.36 ES- 37.29
2. 86.5gn - 2686, 2669, 2677 SD- 8.43 ES- 16.84
3. 87gn - 2679, 2684, 2696 SD-8.42 ES- 16.4
4. 87.5gn - No velocities, error on the lab radar. My fault.
5. 88gn - 2709, 2712, no reading on the 3rd. SD- 1.99 ES- 2.81
6. 88.5gn - 2720, 2732, 2725 SD- 5.9 ES- 11.79
7. 89 gn - 2741, 2737, no reading on the 3rd SD- 3.36 ES- 4.75
8. 89.5gn - 2762, 2757, 2775 SD- 9.75 ES- 18.86
9. 90gn - 2770, 2777, 2780 SD- 5.13 ES- 10
(No noticeable pressure signs at 90)

Thanks in advance for any advice!

Jeff

 

[Stevewallis]

Any help or suggestions would be much appreciated. I'm pretty new to reloading and have been struggling to find a load for this rifle. Thanks

 

[Hollywood]

Any help or suggestions would be much appreciated. I'm pretty new to reloading and have been struggling to find a load for this rifle. Thanks

I would explore the 41/41.5. Little vertical spread and low SD.

 

[Bart B.]

Load developing for an F T/R .308. Lapua brass, Berger 200.20x's, Varget, BR2 primers, Bartlein 30"

48 grains of IMR4350 under 200 grain bullets won a lot of matches and set records in 308 Win ammo and 1:11 twist. That powder and charge typically had 2500 to 2550 fps in 26" barrels with single digit SD numbers with Sierra 200 HPMK's. Perhaps 90 fps more in yours may happen. Faster powders never did as good.

I watched the prone 600 yard match rifle record 200-19X (a 4" group) set in the late 90's using Rem small primer 308BR cases with the 48 grain load. Pretty good using aperture sights.

 

[Stevewallis]

I would explore the 41/41.5. Little vertical spread and low SD.

I would explore the 41/41.5. Little vertical spread and low SD.

Thanks Hollywood I'll give it a try!

 

[josebd]

How about these groups? .308,varget,30"criterion barrel.100 yards
43.5

44.0

44.5

45.0

 

[Bart B.]

More statistically equal groups.

 

[josebd]

43.5 best?

 

[David Christian]

@josebd,

Your POI is shifting bottom to top between 43.5, 44, and 44.5. It seems to be the same between 44.5 and 45. I might suggest that you retest these same loads, but increment by .2 instead of .5 so that you can see where your node might stabalize with the POI shift.

 

[josebd]

I was told 43.5 was better because of less vertical