9mm 115 gr TMJ, OAL question???

[THE COOP]

I'm all set up and ready to reload, I'm using 115 gr TMJ/FMJ bullets and my Lyman's 49th edition doesn't have a recipe for this load, it does have it in JHP but I need a good OAL recipe for FMJ, I know I need to buy another book but does anybody have there book close they can give me a recipie for 115 gr using Unique powder and the OAL? Thanks COOP

[Guest Gary]

Here's a link to a load reference site: Load Data

[MemphisMechanic]

When in doubt, guess long.

Most manuals will go VERY short on length. Somewhere in the realm of a 1.100-1.110" length, and that is what you'll see from a lot of factory ammo. When in doubt, go with the lighter powder charge, and the longer OAL, and work your way up to anything resembling a max load.

Most competitive shooters (particularly those running a 1911 in 9mm) load extremely long by comparison. My loads for my Glock 34 were 1.145" ... and theirs were typically in the 1.160" neighborhood.

(SAAMI max spec for the 9mm is 1.169" OAL.)

The reason I recommend that you load long, is that pressures will be lower than a short round, because of the additional case volume. I would have recommended a length of 1.125" off the top of my head, as that is a bit longer than many manuals start with, and I have never found a pistol that won't feed a 115gr in that length.

Guess what? The powder manufacturer agrees.

Alliant Powder - Reloader's Guide

By the way, you can treat a TMJ like an FMJ when it comes to velocity - it's a bit cleaner due to the lack of an exposed lead base, but the jacket results in velocities pretty much identical to a standard FMJ. Yes, I've chrono'd both and speak from experience with a Speer 147 TMJ and a Precision Delta 147 FMJ with the same powder charge under both of them.

Their websites velocity (1233 from a 4" barrel is a pretty hot load) would probably have me start with 6.1gr at 1.125" OAL, and work up. 6.3 could turn out to be a bit... snappy.

Edited March 18, 2010 by MemphisMechanic

[THE COOP]

When in doubt, guess long.

Most manuals will go VERY short on length. Somewhere in the realm of a 1.100-1.110" length, and that is what you'll see from a lot of factory ammo. When in doubt, go with the lighter powder charge, and the longer OAL, and work your way up to anything resembling a max load.

Most competitive shooters (particularly those running a 1911 in 9mm) load extremely long by comparison. My loads for my Glock 34 were 1.145" ... and theirs were typically in the 1.160" neighborhood.

(SAAMI max spec for the 9mm is 1.169" OAL.)

The reason I recommend that you load long, is that pressures will be lower than a short round, because of the additional case volume. I would have recommended a length of 1.125" off the top of my head, as that is a bit longer than many manuals start with, and I have never found a pistol that won't feed a 115gr in that length.

Guess what? The powder manufacturer agrees.

Alliant Powder - Reloader's Guide

By the way, you can treat a TMJ like an FMJ when it comes to velocity - it's a bit cleaner due to the lack of an exposed lead base, but the jacket results in velocities pretty much identical to a standard FMJ. Yes, I've chrono'd both and speak from experience with a Speer 147 TMJ and a Precision Delta 147 FMJ with the same powder charge under both of them.

Their websites velocity (1233 from a 4" barrel is a pretty hot load) would probably have me start with 6.1gr at 1.125" OAL, and work up. 6.3 could turn out to be a bit... snappy.

Thanks for the info, I ended up with a OAL of 1.100 and 5.0 grns of Unique and they seem fine, loading long to reduce pressures helps accuracy? I did buy another reloading book so I have some additional info. COOP

[SpacemanSpiff]

I go between 1.155 and 1.160 as well. I have a Glock 19 and 26 plus a Sig P229 so I make sure that the OAL that I choose will fit and feed properly in all 3 guns.