Bullet question

[TX1911fan]

I'm new to reloading, so I hope this isn't a stupid question. In all the reloading manuals I look in, it has a specific type of bullet mentioned. For example, Hornady always uses their bullet. If the load for a 230 grain LRN from Hornady is 4.6 grains of Titegroup, will that be the same for a 230 grain LRN from anyone else?

Also, I am assuming that if I buy a 124 grain bullet I need to find a recipe for that 124 grain bullet, and not try to fudge on a 125 grain bullet recipe, correct?

And, one final question. How much does the shape of the bullet matter in the charge?

Thanks.

 

[rcmodel]

Pretty much yes, you can use other data for the same shape & weight of lead bullet.

Factors that effect pressure are bullet shape, because of different bearing surface length causing more or less friction.
And alloy hardness, to a lesser extent.

There is no problem substituting 125 grain lead data for 124 grain lead data, if the shape & bearing surface are very much alike.

There is quite often much more then one grain differance in bullet weights with cast lead bullets out of the same batch.

rcmodel

 

[TX1911fan]

Got it. But I wouldn't want to substitute data between lead and jacketed, right?

 

[cdrt]

Correct. There are differences between the two.

 

[FieroCDSP]

The largest difference between lead and jacketed is the pressure involved. Jacketed loads can burn a lot hotter, giving you higher velocities. If you use the same charge for lead, you'll usually have serious leading issues, as the hotter load melts the back of the bullet and vaporizes lead, rather than expanding it.

Most bullets of similar weight and shape are close to the same length. If you notice an obvious difference in length, use caution with upper and max-pressure loads, as seating too deep can spike pressures and Ka-boom, especially with fast powders and 40S&W.