158 SWC with SR4756 in 357 Mag Load Suggestions?

[Matt 357]

I ordered some 158 grain SWC Action! Bullets from Missouri Bullets. I have some SR4756 and Winchester Small Pistol Primers I'd like to use.

What is a good starting load for SR4756?

The Hodgen website lists a max load of 6.5 with 158 gr MeisterCast LSWC but the primer is not really specified (assume magnum primer?).

The Speer #8 Manual lists a max load of 11 with 158 gr Speer SWC and small pistol primer.

The IMR Data from 2005 lists a max load of 7.7 with 158 gr Rem LSWC and small pistol primer.

I am loading for a 6" GP100.

Any suggestions?

P.S. When my SR4756 runs out is there a good powder that works with small pistol primers?

 

[Walkalong]

When my SR4756 runs out is there a good powder that works with small pistol primers?

In that approximate burn rate, Unique. AA #5, N340, True Blue.

 

[rcmodel]

Alliant Unique for mid-level to low high end .357 loads.

Alliant 2400 for high end .357 loads.

Neither powder requires Mag primers.

rc

 

[Stumper]

I have found 4756 to be a very useful handgun powder but it is somewhat disconcerting trying to develop loads due to the extreme variations in loading data. FWIW, Hodgdon themselves have older Jacketed data that goes to 8.2 grains under a 160 for 35.3kCUP. I'd start around 7gr and move up until you have the performance you want or,at most, based on Dupont data and others from previous times stop at around 9.5 under cast 158s

 

[kelbro]

I have found 4756 to get very 'spiky' as you go up in the charges. Proceed with caution.

 

[ColtPythonElite]

For LSWC, Unique is hard to beat.

 

[Matt 357]

Thanks for the input. Looks like Unique and 2400 are pretty popular. I'll probably pick up at least one of them next time I restock. Do they meter well with the Lee "Perfect" Powder Measure?

Right now I am using 6.5 of SR4756 under Rem SJHP with a magnum primer. Works pretty well. Middle of the road. Clean burning.

When switching to the MBC 158 SWC Action, should I back down? How much?

Any problems using a non-magnum primer with SR4756 and the MBC 158 SWC Action?

The range of published load data in my original post had me scratching my head.

 

[Peter M. Eick]

My last IMR manual (april 2004) says 7.7 grns is max load of 4756 and a 158 lead.

Me? I would start at 6 grns and work my way up toward the 7.7 grns and see what felt right with no pressure signs.

 

[jfh]

The load range Peter quotes is about what I shot a couple of years ago, with fairly extensive testing. At 7.4-7.6 gr. under a 158 LSWC I was running about 1100 fps from a 4" barrel (686), and I don't think a 6" barrel will run much faster.

My computer notes do not show anything in comments--but 4756 can be quite position sensitive. I would also shoot over a chronograph, as at the upper end of the recipe, the benefits were diminishing quickly.

Jim H.

 

[ChuckS1]

Based on my experience with the .38 Special 158 grain LSWC loads using 4756 in Speer #8, I would start 20% below the minimum load and work carefully up. I started 10% below the listed minimum and never made it to the minimum load below I got pierced and flattened primers. I would suggest looking at another source before relying on Speer #8.

 

[Walkalong]

4756 can be quite position sensitive

Worth repeating.

 

[Matt 357]

Actually SR4756 wasn't my first choice. They were out of 2400 when I was placing my order. I didn't read about the position sensitivity until after the purchase. Seemed to work okay with the 158 gr SJHP.

Any issues using non-magnum primers with SR4756?

 

[Peter M. Eick]

I don't use mag primers with 4756.

I do know that there is a large lot to lot variation. I have seen it just in different bottles.

I like it enough that next time I order, I will get either an 8 or a 4 lb jug. It works well enough in 38 super that I will continue to use it. I just want one lot so I can work up a load and stick with it.