o.a.l. of handloads

mundumugu · August 14, 2001, 05:13 AM

In various loading manuals, I have seen different O.A.L of .357 mag cartriges, and in others too. Also, some very different max. loads. An old speer man. gives 17.5 grains of H110 for a 180 gr. bullet, Lyman gives 15.0.
O.A.Ls for a 180 gr. bullet varied from 1.550 to 1.595.
Now, what? any help is apreciated. I intend to load 180s cast truncated cone that, in my handloads, measure 1.55" o.a.l., and 15 gr. of H110. thanks in advance.

Chris McDermott · August 14, 2001, 05:28 PM

OAL depends on the bullet shape & where the crimp groove is (if you use it); more than a bullets weight. Bullets with a short nose, that put most of the bullet inside the case, will have a short OAL, and also a lower max powder charge as there is less room in the case for powder. Bullets with a long nose will have more of the bullet outside the case, and so have a long OAL and a heavier powder charge as there is more room in the case for the powder - not just room for the powder to fit in, but also a larger space to hold the resultant gases [go back to your high school chemistry - if you have the same amount of gas molecules from burning the same amount of powder, the more space those gas molecules have to move in the less pressure & temperature; to maintain a given pressure in a larger space you need more molecules, so you use more powder].

You can either follow the manual that lists the exact bullet you have (a good reason to have a load manual by your favorite bullet manufacturer), or start low and gradually work up your load, watching carefully for pressure signs.

August 14, 2001, 05:13 AM	#1
mundumugu Member Join Date: July 12, 2001 Location: Brazil Posts: 46	o.a.l. of handloads In various loading manuals, I have seen different O.A.L of .357 mag cartriges, and in others too. Also, some very different max. loads. An old speer man. gives 17.5 grains of H110 for a 180 gr. bullet, Lyman gives 15.0. O.A.Ls for a 180 gr. bullet varied from 1.550 to 1.595. Now, what? any help is apreciated. I intend to load 180s cast truncated cone that, in my handloads, measure 1.55" o.a.l., and 15 gr. of H110. thanks in advance.

August 14, 2001, 05:28 PM	#2
Chris McDermott Senior Member Join Date: March 30, 2000 Posts: 245	OAL depends on the bullet shape & where the crimp groove is (if you use it); more than a bullets weight. Bullets with a short nose, that put most of the bullet inside the case, will have a short OAL, and also a lower max powder charge as there is less room in the case for powder. Bullets with a long nose will have more of the bullet outside the case, and so have a long OAL and a heavier powder charge as there is more room in the case for the powder - not just room for the powder to fit in, but also a larger space to hold the resultant gases [go back to your high school chemistry - if you have the same amount of gas molecules from burning the same amount of powder, the more space those gas molecules have to move in the less pressure & temperature; to maintain a given pressure in a larger space you need more molecules, so you use more powder]. You can either follow the manual that lists the exact bullet you have (a good reason to have a load manual by your favorite bullet manufacturer), or start low and gradually work up your load, watching carefully for pressure signs.