Best rifle for. 9 yo youth

[Wind Gypsy]

I was thinking more of the process of working up a load. How do you know where to start if you're introducing an unknown variable?

Are you saying a change of less than 0.010" in seating depth impacts the load density and time/pressure curve in a way that you can calculate and predict the outcome of had you known the exact change in seating depth (like does it move 3 thou or 6 thou) prior to starting load dev? Or are you saying the jam will change seating depth differently from round to round?

It does seem like seating to jam is still pretty common in some shooting disciplines. I've never done it because it's not practical for field shooting or the disciplines that interest me.

 

[Jerry-B-WI]

Are you saying a change of less than 0.010" in seating depth impacts the load density and time/pressure curve in a way that you can calculate and predict the outcome of had you known the exact change in seating depth (like does it move 3 thou or 6 thou) prior to starting load dev? Or are you saying the jam will change seating depth differently from round to round?

It does seem like seating to jam is still pretty common in some shooting disciplines. I've never done it because it's not practical for field shooting or the disciplines that interest me.

No, I'm saying that if I look up a particular cartridge in a loading manual and it gives a start and maximum load for a given powder, bullet weight, primer and O.A.L. Then I seat the bullet out far enough to jam into the rifling another .010 what effect will it have on the time/pressure curve. And I may have to do this for a number of loads until I find the one that's the most accurate. I don't know if benchrest shooters use compressed loads or not, but I do know that some powders in certain cartridges it is acceptable to have a compressed load.

 

[Wind Gypsy]

No, I'm saying that if I look up a particular cartridge in a loading manual and it gives a start and maximum load for a given powder, bullet weight, primer and O.A.L. Then I seat the bullet out far enough to jam into the rifling another .010 what effect will it have on the time/pressure curve. And I may have to do this for a number of loads until I find the one that's the most accurate. I don't know if benchrest shooters use compressed loads or not, but I do know that some powders in certain cartridges it is acceptable to have a compressed load.

I see, so you’re saying it’s likely less predictable in regards to how much the jam increases pressure? If so, I’d agree. But I don’t think it’d be too hard to do a quick 1 shot velocity /pressure ladder just like one would do if they switched to say brass with less capacity and needed to redo load work up.