bullet type OAL and case volume question

[LegionShooter]

Headed out to test fire first reloads tomorrow. I have PD 180 RNFP that are set at 1.178 (reading between 1.176 and 1.180 when I measure them). I just ran some dummy rounds with BBI 180s that are reading 1.215 with same seating die. If I reset the die to get the BBI to 1.18 OAL how much do I need to worry about the decrease in case volume causing pressure issues?

I'll be working up a load for 3N37 and now for N320 which I just got from FedEx about 10 minutes ago. How many different powder charges does everyone tend to take to the range on the first go and in what increasing increments?

[Hi-Power Jack]

If these are "first reloads", I'd keep them all under Major.

Work up slowly to Major with the .40.

[earthshine402]

if i were you, i would adjust the seating die to the desired OAL for each bullet, not use one die setting for different bullets.

[LegionShooter]

if i were you, i would adjust the seating die to the desired OAL for each bullet, not use one die setting for different bullets.

Understood. If I decide to run both the PDs and the BBIs at 1.18 though, would I have to adjust powder charge to compensate for lesser case volume? Or is the difference not enough to be concerned with since both are 180gr bullets?

Edited May 16, 2014 by LegionShooter

[Brenden]

if i were you, i would adjust the seating die to the desired OAL for each bullet, not use one die setting for different bullets.

Understood. If I decide to run both the PDs and the BBIs at 1.18 though, would I have to adjust powder charge to compensate for lesser case volume? Or is the difference not enough to be concerned with since both are 180gr bullets?

Start with a well below max powder charge, the one with less case volume will have higher pressure. A chronograph is very useful in this situation, you could find that both bullets yield a similar fps.

[Jakobi]

Every time you change a component (powder, primer, or bullet) you should start load development over.

EVERY.

TIME.

If you're being really picky (like I am with rifle ammo) then you would also start over when you change what brass your are using.

-Jake

[earthshine402]

Every time you change a component (powder, primer, or bullet) you should start load development over.

EVERY.

TIME.

If you're being really picky (like I am with rifle ammo) then you would also start over when you change what brass your are using.

-Jake

Don't worry about brass with .40. Waste of time. The only instance I can think of where it might be meaningful is if this is for bullseye shooting.

Develop each load independently. I really don't like the idea of using the same seating setting and getting different OALs and worrying about case volume. This seems a bit lazy. Develop the loads with a chrono as someone else mentioned and you should get some meaningful results.

[jimbullet]

LegionShooter,

I would be interested in what you find (change in velocity) using the two different ammo's (1.215 and 1.180 OAL) of 180 gr projectiles.

Interested to see the spreads on yours.

[LegionShooter]

LegionShooter,

I would be interested in what you find (change in velocity) using the two different ammo's (1.215 and 1.180 OAL) of 180 gr projectiles.

Interested to see the spreads on yours.

Ran the 1.18s yesterday but haven't run the 1.21s yet. I'll put up the spreads once I do though.

[tac_driver]

start at least 10% of max and work up using a chronograph

if you change any component of the load start over

you can't be too safe when reloading ammo

check every round for proper powder depth