OAL questions and bullets weights

[Giant81]

First I want to start off that I'm a noob reloader and had a couple questions.

1) If I am trying to develop a load to work with a specific type of bullet and they do not have one, can I use a powder level of a bullet that's the same weight? So say I'm looking for a 124gr round nose but they only have a 124gr Hollow Point, can I use that to start with? What about 124gr flat nose? I take that as long as they are the same jacket and weight that's all that really matters at that point?

2) If I'm trying to find a good OAL, but they do not have the bullet type I have listed, can I use the OAL of a similarly shaped bullet? So say I have an OAL for a 124gr HP and need one for a 124gr Flat Point can I use it? Or say I'm reloading 115gr RN and I only have an OAL for 124gr RN, will different weights be seated at different depths? I suspect the portion of the bullet that is outside the case is not the important part as long as it feeds and headspaces right. I'm pretty sure the most important value is the amount of case volume under the round in relation to the amount of powder + weight of the bullet. So if I have the OAL of a bullet .08" longer than the round I'm reloading, I can reload to an OAL .08" shorter given the same weight and jacket?

[lee blackman]

1) Yes....

2) Its a hit or miss thing here. You run into feed issues. A little batch trial and error testing is in order. The major thing you need to pay attention to with seating depth is if your compressing a powder charge or not.

Other problem you can run into with seating depth and bullet design is premature slide lock... Sometimes, especially with heavier bullets like 147gr RNs, the nose area or part that rounds from the body of the bullet to the tip sticks out higher allowing it to touch the nub on the slide lock lever as its raising to the top of the magazine just before it sits in the feed lips. I had this problem with several of my 9mm's with 147gr plated round nose, and turned out the solution was shortening the OAL.

[Giant81]

so if I do decide to seat a little deeper, do I back off the load a few tenths of a grain and work back up just to make sure I'm not putting too much powder in too small a space?

I've also heard of the possibility of too LITTLE powder causing an over pressure issue? Anyone know how that happens?

Edited March 8, 2012 by Giant81

[Hi-Power Jack]

so if I seat a little deeper, do I back off the load and work back up ?

The 9mm case is relatively small, and holds only about

10 grains, or so, of pistol powder.

But, if you're loading 9mm minor (standard loads), and

using standard pistol powders, you're probably using

about 3 -5 grains (case is only half filled).

So, it's really unlikely you'll change anything significantly

by going from 4.2 to 4.5 grains of anything like WW231.

As long as your OAL is around 1.1 -- 1.4".

There may be exeptions, but I can't think of any yet???

Anybody disagree?

Jack