Load development question - seeking advice

[CharlieNC]

I think Optimum Charge Weights and Barrel Times for best accuracy are another pair of myths.

Having seen several barrels of the same make, length and profile shoot the same lot of ammo well into sub MOA at 300 to 600 yards and average muzzle velocity across them is 50 fps or more, that counters all their theories. Some of those barrel's bore and groove diameters belled out .001" or more the last half inch of their length; no copper wash there. Bullet jump distance to rifling across all barrels had a spread of .040" or more; less for barrels with only a couple hundred rounds through them, more if a couple thousand.

You don't believe nodes are associated with barrel harmonics? What then?

 

[Mulligan]

I think Optimum Charge Weights and Barrel Times for best accuracy are another pair of myths.

Having seen several barrels of the same make, length and profile shoot the same lot of ammo well into sub MOA at 300 to 600 yards and average muzzle velocity across them is 50 fps or more, that counters all their theories. Some of those barrel's bore and groove diameters belled out .001" or more the last half inch of their length; no copper wash there. Bullet jump distance to rifling across all barrels had a spread of .040" or more; less for barrels with only a couple hundred rounds through them, more if a couple thousand.

I am going to assume you and I define accuracy differently. We surely have different foundations in science.
Going back to painting the house
CW

 

[billlarson]

Those groups are statically the same size.

Shoot at least 15 shots per load; 20 is better.

I will strongly disagree.......why would you want to wear out a barrel that way..??????...
3 shot groups are fine...... maybe 5-6 groups....pick one then.....shoot some 5 shot groups changing seating depth....more 3 shot groups..... in .005" increments...
Then..... with your best load and how you use the gun/load...prairie dogs,silhouette,palma,"F" class... shoot a couple longer strings to duplicate intended use to find out how the barrel acts as it heats up......
with a decent barrel you should have most of the info you need..... in less than 100 rnds.
bill larson

 

[jdj71]

mjgillen re: case volume Burn a fixed amount of fuel(powder) in a given space(case) gives a certain pressure, increase the space, burn the same amount of fuel and the pressure is reduced (more room to expand) You can see why bullet seating depth plays a part in this also.

 

[.22gongzilla]

That board you've posted is well done, reminds me very much of the groups I went through with my new barrel. Take the top line - on the left is a well distributed group at 22 grains and IMO you won't need any more than that until the bore starts smoothing out. Nice job.

 

[mjgillen]

I won't be able to do more testing for a couple of weeks and will report back to this thread when I have shot some more groups.

Thank you to all that have replied to this thread and those that sent me a PM. Much appreciated!

Michael

 

[Toejoe12]

You're in the upper node at 24.5 and 25. Load some at 24.8 at different jumps and I think you will find what you're looking for! Temp won't have much effect as well in that area.

 

[.22gongzilla]

Temp won't have much effect as well in that area.

...valuable information which I might have used myself during load development and barrel break-in. I'm no expert by any means so IMHO this underscores the value of multiple user input and perspective...