Are starting loads an arbitrary 10% of maximum loads? Can we go lower with Titegroup?

5.4 gn is the starting Titegroup load for a 158 gn Hornady XTP and 4.5 gn for a 158 gn LSWC in .357 Magnum cases. The bullets are the same weight in the same case. I've loaded 5.2 gn with good precision with the XTP bullet but I'd like to get its velocity down to subsonic for our range.

5.2 gn Titegroup averaged 1139 fps with a StdDev of 8.35 in one of my tests. 5.3 gn was no different.

I've read you don't do that with slow burning powders. However, Titegroup is the ninth fastest of 127 powders published in the Lyman Reloader Handbook.

Why shouldn't I try 5.1 gn or 5.0 gn Titegroup with a 158 gn XTP jacketed hollow point if a 158 gn LSWC in the same case can start at 4.5 gn?

I'm shooting with a 24" Winchester 1873 Sporter chambered in .357 Magnum/.38 Special.

Thanks for the advice other than change powder and/or bullet. I have ACME 38 158 SWC-NLG Coated bullets on order and I plan to buy some Alliant Bullseye tomorrow for more subsonic .357 Magnum research.

Be very careful when loading down as the chance for issues goes up as you go down. I would never load down below manufacturers recommended low. Others do it but...
.357 brass would be a poor choice for reduced loads. You will have more success using .38 brass. .357 loads will "flash over" with that much empty case to powder. JMO.

Thanks for the caution and suggestion. I've ruled out .38 Special brass in my testing because it has poor precision with having 0.125" more freebore than what there is with a .357 Magnum cartridge in my Winchester 1873 Sporter.

I'm not too concerned with how much air space there is in the case when using fast burning Titegroup. The 0.9 gn lower load for a lead bullet will have more space in the case. An advantage with Titegroup is it will burn readily and evenly regardless of how it's spread out in the case.

One friend talked about needing more pressure to push a copper jacketed bullet through the bore than what is needed to push a lead bullet. Thus if the load is too low it might cause a squib.

Another friend said to look for signs of high pressure as I progressively fire lower loads.

Another Dang 9 wrote: Tue May 07, 2019 5:01 pm Be very careful when loading down as the chance for issues goes up as you go down. I would never load down below manufacturers recommended low. Others do it but...
.357 brass would be a poor choice for reduced loads. You will have more success using .38 brass. .357 loads will "flash over" with that much empty case to powder. JMO.

+1

Alliant web site has .357 cowboy loads published...down to 4.0 and 4.5 gr of unique. Verify for yourself before loading. They also have mild loads for Bullseye and American Select powders.

PAndy wrote: Wed May 08, 2019 5:43 am Alliant web site has .357 cowboy loads published...down to 4.0 and 4.5 gr of unique. Verify for yourself before loading. They also have mild loads for Bullseye and American Select powders.

I noticed that too. I had planed to get some Bullseye this morning. Instead, I'm going to test the ACME 38 158 SWC-NLG Coated bullets due to arrive in the mail today. I'll start with the minimum load for 158 gn LSWC.

I'll keep y'all posted in case anyone is interested.

Thanks!

The ACME 158gn SWC-NLG with 4.3gn Titegroup in .357 Magnum case gave a respectable 7.14 MOA for coated lead but not good enough for me. I tried Trail Boss and the group opened up a lot. The Avg velocity was 1121 with a 20.36 StdDev & a Max 1156. Too fast for our range.

The winner is 158gn Hdy XTP and 5.0gn Titegroup in .357 Magnum case. The Avg velocity was 1101.8 fps, StdDev 17.77 with Max 1120 fps. I reduced freebore with a 1.595" COL. 24" Winchester 1873 Sporter

Hornady list as low as 3.1 Titegroup for 158g cast lead rifle data.

Ojaileveraction wrote: Fri May 17, 2019 8:17 pm Hornady list as low as 3.1 Titegroup for 158g cast lead rifle data.

What's your source? Is it a Hornady manual or website? Hodgdon's starting load is 4.5gn Titegroup from their website.

Hornady Cowboy Load Data.
Get , Loadbooks USA, OneBook,One Caliber, The Complete Reloading Manual for the 357magnum

Sporty wrote: Sat May 18, 2019 4:39 am

Ojaileveraction wrote: Fri May 17, 2019 8:17 pm Hornady list as low as 3.1 Titegroup for 158g cast lead rifle data.

What's your source? Is it a Hornady manual or website? Hodgdon's starting load is 4.5gn Titegroup from their website.

I've used Rainer plated bullets with Unique. Had good luck with those.

The need to shoot subsonic loads at the PC Silhouette Matches at the Piedmont Gun Club, Rutherfordton, NC has been rescinded.

Now I can work on improving my .357 Magnum loads with higher velocities.

Sporty,
I'm getting great results with Rainer plated 125gr at c/p/t with 13gr of HMR 4227 and Rainer plated 158gr at Rams with 7.5gr of Unique. Rifle is a 357 Rossi 24 inch Octagon.
ppkny

ppkny wrote: Fri Jun 14, 2019 3:03 am Sporty,
I'm getting great results with Rainer plated 125gr at c/p/t with 13gr of HMR 4227 and Rainer plated 158gr at Rams with 7.5gr of Unique. Rifle is a 357 Rossi 24 inch Octagon.
ppkny

Do you crimp those?