IMR SR 4756 Max Load with 158 SJHP in 38 Special?

[Matt 357]

According to the Hodgens data, the max load for 38 Special with 158 gr Hornady XTP is 5.3 grains. I am actually using Remington 158 gr SJHP bullets. My weapon of choice is the 6" stainless GP-100. I know... why reload 38 for the GP-100. The anwser is that I just got into reloading and had a crap load of white box winchester cases.

Using 5.3 grains with my bullets resulted in some unburned powder (a few flakes here and there) and lots of carbon on the spent cases. Much worse than the Winchester white box 38s. Reading on the web, this problem may be related to insufficient pressure. A firmer crimp is recommended. My first batch had a light to medium crimp. I'll try a firm crimp on the next batch.

I am also wondering if increasing the charge a bit would help. I know the answer is to start low and slowly work your way up. I also know it will vary from gun to gun. How many folks are loading more than 5.3 grains of SR 4756 with a 158 grain SJHP 38 special bullet? If so, how much, what bullet, what case, and what gun?

 

[Walkalong]

I am not looking at any data right now, but sounds like it is low pressure for sure. SR-4756 burns real clean, but is also very position sensitive. Any powder that is not burning completely and charring the cases will burn better with more powder (pressure) if there is room in the data to up the charge.

 

[Walkalong]

Just checked Hodgdon, and 5.3 is max with a 158 Gr XTP. I believe Speer shows a higher charge, but am not where I can check it.

SR-4756 is not the best choice for .38 SPl IMHO.

 

[Steve C]

If you check .38 spl +P data it jumps to 5.5grs of SR 4756 with the 158gr XTP. Up your load to the top of the +P data and see if that doesn't help. Consider changing primers if you are using CCI try Winchesters as they run a bit hotter or try a magnum primer.

You are certainly not going to get up to anywhere near magnum pressure with any component mix using .38 spl +P data so you'll be safe using them in your GP100.

While you can go heavier in the .38 (up to magnum start charge levels) I am not a fan of putting over pressure loads that are near or at ,357 magnum levels in the .38 spl even though they'd be perfectly safe in a .357 mag. You never know who may get hold of one of your reloads including yourself and stuff it in a .38 revolver.

 

[Matt 357]

Sorry, left out the primer info. I am using Winchester Small Pistol which is specified by Hodgens for 38 special SR4756.

Does anyone know if the XTP is much different than the Remington SJHP? Head space, canulare, contact length in barrel, etc?

 

[Stumper]

Sr4756 in the .38 special has been the subject of almost interminable debate on reloading forums. The reason being that old Speer and Sierra manuals listed loads of 8-9 grains of 4756 under 158grain bullets in .38 Special........then those loads disappeared and were replaced by loads of less than 6 grains that don't burn well and yield less than standard velocity for the cartridge. Having experimented with both old and new lots of 4756 in 38 special using a .357 magnum revolver for safety, my own conclusion is that the powder formula/performance has not been changed but I suspect that once upon a time there may have been an abnormally slow lot of 4756 that was used in by Speer and Sierra to develop some hot loads back in the 38-44 era when the pressure standards were less conservative and later an abnormally fast lot of 4756 caused some grief. I do NOT advocate loading those old Speer # 8 and Sierra #2 loads in .38 Specials but I do not believe that the current recommendations are realistic either-I think that all current data and pressure figures must be based upon the fastest lot of 4756 ever produced- they do not match real world performance. I have an old Dupont manual with pressure tested data that recommended 6 grains of 4756 in .38 special for a standard pressure load yielding standard velocity and 16,000 CUP. THAT data correlates with the performance of every lot of 4756 that I have experimented with. My personal choice has been to use my stock of 4756 for 9mmx19 and use Unique and Power Pistol in the .38........but that is because I deplore violating the currently published data. I really have no fear of 6 grains of 4756 with 158gr.38Spl.

 

[Matt 357]

Thanks Stumper. I was sweating going to 5.4 grains.

 

[Peter M. Eick]

Stumper,

That is a very good write-up on 4756. Nice job. You pretty much captured my understanding of 4756 also. The only difference is that I shoot 38/44's a lot and I run up to the old "book max" loads. 8 grns out of my 38/44 heavy dutys with a 158 is a nice decent load. I would not shoot it out of my Diamondback though.

Matt, I would not worry about 5.4 grns but I would not expect your performance to be very good at such low pressures. That is below where I even started my work up. Obviously your mileage may vary, so work it up slow till you get the performance you feel is safe and comfortable in light of modern loading manuals. Just keep in mind that most of us quoting higher loads are shooting lead bullets in either 38/44's or 357 mags.