Question stemming from another post

[Walter]

'gearyr' posted a request for load data for a Nosler 180 gr. bullet.

Smokey Joe replied that if gearyr wanted Nosler bullet data he really should
get a Nosler manual.

My question is this: Isn't loading data pretty much the same regardless of
the brand of the bullet, as long as the bullets are very close in configuration
and weight? For example, a Nosler 180 gr. boattail, and a Hornady 180 gr.
boattail softpoint. It seems to me that a given safe load for one should be
perfectly safe for the other.

I know there are exceptions to the rule, such as the Barnes solid copper bullet, and maybe even some all-lead bullets. But am I wrong in my thinking?

If I am wrong, I am going to have to go buy a few more reloading manuals.

Walter

 

[HSMITH]

Bullet construction has a lot to do with it. Some bullets have thicker jackets which increases pressure for instance. I have used 'generic' loading data but I have always backed down. Better safe than sorry.

 

[rwilson452]

Bullets vary

It's my understanding the three major factors that determine the pressure are
Weight, hardness and bearing surface. The bearing surface is that part of the bullet that contacts the bore. When speaking of jacket hardness, to listen to the bullet mfg each has their own special formulation for the jacket material thus a different hardness. If you substitute one bullet for another of the same general type. For example a Hornaday .30 cal Spitzer for a Sierra .30 cal spitzer they will be very close. If you start with the recommended starting powder load either would be safe. where the max is would vary a bit. How much it would be hard to tell. As an after thought, it has been my observation that max loads tend to loose accuracy for little gain in power on target. Not to mention it's harder on the gun and shortens case life.

Now for lead hardness. I have seen it vary all over the place.

 

[Ackley Improved User]

Bullet construction is VERY important.

Bullet compressibility (stiffness/hardness) and bearing surface are very important in determining pressure. It takes more pressure to push a stiff bullet with a relatively large bearing surface down the barrel - and, it is important, that these two factors vary with bullet design.

For example, I've found that Nosler BT bullets tend to be "softer" than Swift Scirroccos - that is, bullet weight being equal. The same powder charge with 180 gr. Scirrocco will create more pressure (and velocity) than when using the 180 gr. Nosler BT. This becomes very important if you're loading HOT - hence, be careful. The Scirrocco has a thicker jacket.

 

[Robert M Boren Sr]

I have most all of the major reloading manuals. I use the manual for the bullet I intend to use. I used to use just sierra bullets all of the time but since the boys grew up and got their own stuff and have been trying different loads on a regular basis, then I've had to buy all of the manuals. You know, now that I have them I have no regrets. Nobody says you have to buy them all at once, but if you want to use a brand of bullet that you don't have the book for, then you really should walk out with the book also. One time buy. Well worth it.