Why does loading LSWC in .44 Mag go beyond SAAMI max. length?

Abbynormal · #1 07-25-2020, 04:46 PM

A buddy and I partnered up on a set of Lyman 429421 Keith LSWC dies. We played around with the lead alloy mixture and cast a few hundred that run between 245 grains and 247 grains.

We sized them and coated them and was setting up my Dillon 550 to start cranking out rounds. I sat up the dies and Rick began adjusting the seating die.

What we noticed was if we seated the LSWC to the crimp grove, we came up with an OL of 1.72". The diagrams in all of the reloading manuals we have show a SAAMI max length of 1.61". A couple of the manuals had photos or drawings of a LSWC loaded to where the top of upper driving band was even with the top of the brass.

We started to do some computer searches and found websites that listed the max OL with the Lyman 429421 to be right where we are if seating in the crimp grove.

I've been loading .44 Magnum on this Dillon since 1988 and this is the first time I've ever noticed SAAMI length being exceeded by a standard seating.

Going through my reloading library, I found this paragraph in the "Lyman Third Edition Pistol & Revolver Handbook":

DumpStick · #2 07-25-2020, 07:55 PM

I think it goes back to Keiths' development of his heavy 44 Special loads, prior to the existence of the 44 Mag.

To get the weight he wanted, he lengthened the nose of the bullet. He couldn't put more bullet in the case, he already didn't have enough room for powder.

When S&W came out with the 44 Mag, the cylinders were too short for Keiths' heavy bullets. The compromise was to crimp the bullet over the front driving band, putting more if the bullet in the case.

Later makers, starting with Ruger, had a longer cylinder. Eventually, SW caught up with the longer cylinder.

sparkyvega · #3 07-25-2020, 09:12 PM

I aldo wondered this for about 30 seconds...it went away after I dropped the rounds into the cylinder and all was good. Now I have better understanding thanks to this post.

Quote:

Originally Posted by Abbynormal

A buddy and I partnered up on a set of Lyman 429421 Keith LSWC dies. We played around with the lead alloy mixture and cast a few hundred that run between 245 grains and 247 grains.

We sized them and coated them and was setting up my Dillon 550 to start cranking out rounds. I sat up the dies and Rick began adjusting the seating die.

What we noticed was if we seated the LSWC to the crimp grove, we came up with an OL of 1.72". The diagrams in all of the reloading manuals we have show a SAAMI max length of 1.61". A couple of the manuals had photos or drawings of a LSWC loaded to where the top of upper driving band was even with the top of the brass.

We started to do some computer searches and found websites that listed the max OL with the Lyman 429421 to be right where we are if seating in the crimp grove.

I've been loading .44 Magnum on this Dillon since 1988 and this is the first time I've ever noticed SAAMI length being exceeded by a standard seating.

Going through my reloading library, I found this paragraph in the "Lyman Third Edition Pistol & Revolver Handbook":

max · #4 07-26-2020, 06:12 PM

The 358429 bullet could also be too long for some 357 cylinders. This is the reason some recommended loading these in 38 special cases.