low powerred 125gr 357 mag

sthomper · December 5, 2014, 02:37 AM

hello

can somone here roughly describe a process and a a powder type and approximate amount (for additional research) that can push a 125gr sjhp at 1300fps (357 mag) out of a 4" barrel??

thanks

jdscholer · December 5, 2014, 08:09 AM

Quote:

125 grain JHP or JSP (Jacketed Hollow or Soft Point)
Bullseye 8.4 gr. 1,550 FPS (this is very hot)

From the pages of M. D. Smith. jd

sixguns · December 5, 2014, 08:19 AM

My factory Hornady 140gr chronograph at 1346 so a 125gr hitting 1300 fps should be easy. That's out of a Ruger GP100 4.2" barrel.

jdscholer · December 5, 2014, 08:43 AM

Quote:

My factory Hornady 140gr chronograph at 1346 so a 125gr hitting 1300 fps should be easy. That's out of a Ruger GP100 4.2" barrel.

Yeah, it's just not a big problem. I have been using the fast burning Bullseye for the lighter bullets and getting real good accuracy. Now that Bullseye is harder to find, (at least around here) I've been using more HP-38, and I think I might like it better. Seems to go through my measure better. jd

**Unclenick** · December 5, 2014, 10:36 AM

Sthomper,

If, by process, you are asking how to reload in general, the first step is to get a book on the subject. It will show you how to clean, resize and decap cases, re-prime the cases, expand the cases, charge them with powder, and seat a bullet. In this instance I will recommend the Lyman Reloading Handbook #49, as their .357 revolver load data uses a SAAMI 4" universal receiver barrel which has a barrel measured the way it is done on a revolver (not including chamber length, as is done for guns other than revolvers). If you have no loading equipment yet and are just exploring the process, a Lee Hand Press kit, a set of Lee 38/357 dies, and the supplies will get you where you want to go. Later, if you decide you need to be able to load more volume, the Hand Press will sill be handy because you can take it to the range in a box to use it for load development on-site.

The Lyman book shows a 125 grain Hornady #35710 XTP JHP bullet seated to 1.590" COL in a Federal 357 Magnum case fired by a CCI 550 primer. Using their pressure and velocity data for Bullseye powder, it appears that about 8.1 grains of Bullseye would hit 1200 fps at about 33,750 CUP or about 26,250 psi in their test gun using those components. It shows 8.6 grains of Unique would do it at about 30,250 CUP or about 23,500 psi. It shows about 8.8 grains of Ramshot True Blue would do it at 34,000 CUP or about 26,500 psi. It shows 8.9 grains of Power Pistol would do it at 31,500 CUP or about 24,500 psi.

In a more complicated process, I used Hodgdon's data for the same bullet from 10" barrels but used QuickLOAD to work out the adjustment ratios of velocities from Hodgdon's 10" barrel to your 4" barrel. With COL still at 1.590", in a Winchester case with a Winchester SPM primer, it looks like 6.3 grains of Tightgroup powder running at 33,000 CUP or about 26,000 psi will hit 1200 fps in a 4" barrel. 7.6 grains of either HP38 or W231 running at about 36,000 CUP or 28,000 psi should hit 1200 fps. 6.3 grains of 700X should hit the number at 38,000 CUP or 30,000 psi. Note that for 700X this is near the published maximum load.

For all powders mentioned, the loads are either below or within the published charge range. The recommended charges of Unique, True Blue and Tightgroup are below the published starting loads (though not by enough to be an issue). For the other powders, the starting loads are:

Bullseye: 6.5 grains
HP38 or 231: 7.3 grains
700X: 4.5 grains

Loads using those powders should be worked up from the starting level in about 0.2 grain steps while watching for pressure signs. Every once in awhile you run into a gun that is maxed out by a starting load. I don't know what gun you have.

Note that, in general, the slower burning the powder and the heavier the charge, the more muzzle flash and recoil and the less clean burning the powder will tend to be. That's why I didn't include any really slow powders for which the charge weights might be twice as heavy.

Nick_C_S · December 5, 2014, 07:32 PM

I don't consider a 125g/357 moving at 1300 fps "low power."

I mean yeah, it's fairly easy to wind up a 125g to 1300 fps (I have a number of recipes that achieve this), but that is still a pretty spunky round.

sawdustdad · December 5, 2014, 09:13 PM

I, too was a little perplexed by the apparent dichotomy of a "low powered/1300fps" round out of a .357 magnum.

I just shoot .38spl loads, or even lower "cowboy" loads when plinking with my .357.

Nick_C_S · December 5, 2014, 11:02 PM

Yeah, and there's no way I'm ever going to attempt 1550 fps with Bullseye - per post #2. I like my guns - and fingers - a lot more than that.

(I never aim for velocity when doing load workups anyway - but that's for another thread.)

jdscholer · December 6, 2014, 12:54 AM

Quote:

125 grain JHP or JSP (Jacketed Hollow or Soft Point)
Bullseye 8.4 gr. 1,550 FPS (this is very hot)From the pages of M. D. Smith. jd

I popped this out there this morning before I went to work, and admittedly was in kind of a hurry. It is listed as a max load for this powder and bullet, and coincides with other published data that I have by Lyman and Speer. I have only gone as high as 8 gr. of Bullseye, and finally settled on 7 gr. which is still pretty snappy. It is very accurate, and one of my favorite 357 loads. My revolver and my fingers are doing fine. jd

745SW · December 9, 2014, 02:40 PM

The Speer reloading manuals I have are the number 10 dated 1987 and number 13 dated 1999. The number 13 uses the psi, transducer method. My original Speer number 10 is an early version probably with a date of 1979/1980 but can’t find it presently.

The later Speer manual no longer lists the fast powders such as Bullseye and 700-X for a JHP 125 grain bullet and the older manual does not have the 38 +P at all. My decades old load of 6.0 grains of 700-X for a 125 grain JHP is lower than the window of 7.8 – 8.3 grains listed in the number 10 manual. According to the number 13 manual my 6.0 grains is 1.0 grain above 38 +P. In recent times I got data from the Hodgdon site for the 125 grain HDY XTP using 700-X. Their max load is 6.4 grains with a psi of 30.4K, that’s within the limit of 35K psi for 357 Magnum. So even by the transducer/psi method I’m OK, I think.

Best to be conservative with fast powders like Bullseye, W231 and 700-X for 357 Magnum for the 124 grain bullet, IMO. This is a maximum bullet weight for a jacketed bullet for this cartridge from what I can tell.

December 5, 2014, 02:37 AM	#1
sthomper Senior Member Join Date: June 17, 2010 Posts: 164	low powerred 125gr 357 mag hello can somone here roughly describe a process and a a powder type and approximate amount (for additional research) that can push a 125gr sjhp at 1300fps (357 mag) out of a 4" barrel?? thanks

December 5, 2014, 10:36 AM	#5
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Sthomper, If, by process, you are asking how to reload in general, the first step is to get a book on the subject. It will show you how to clean, resize and decap cases, re-prime the cases, expand the cases, charge them with powder, and seat a bullet. In this instance I will recommend the Lyman Reloading Handbook #49, as their .357 revolver load data uses a SAAMI 4" universal receiver barrel which has a barrel measured the way it is done on a revolver (not including chamber length, as is done for guns other than revolvers). If you have no loading equipment yet and are just exploring the process, a Lee Hand Press kit, a set of Lee 38/357 dies, and the supplies will get you where you want to go. Later, if you decide you need to be able to load more volume, the Hand Press will sill be handy because you can take it to the range in a box to use it for load development on-site. The Lyman book shows a 125 grain Hornady #35710 XTP JHP bullet seated to 1.590" COL in a Federal 357 Magnum case fired by a CCI 550 primer. Using their pressure and velocity data for Bullseye powder, it appears that about 8.1 grains of Bullseye would hit 1200 fps at about 33,750 CUP or about 26,250 psi in their test gun using those components. It shows 8.6 grains of Unique would do it at about 30,250 CUP or about 23,500 psi. It shows about 8.8 grains of Ramshot True Blue would do it at 34,000 CUP or about 26,500 psi. It shows 8.9 grains of Power Pistol would do it at 31,500 CUP or about 24,500 psi. In a more complicated process, I used Hodgdon's data for the same bullet from 10" barrels but used QuickLOAD to work out the adjustment ratios of velocities from Hodgdon's 10" barrel to your 4" barrel. With COL still at 1.590", in a Winchester case with a Winchester SPM primer, it looks like 6.3 grains of Tightgroup powder running at 33,000 CUP or about 26,000 psi will hit 1200 fps in a 4" barrel. 7.6 grains of either HP38 or W231 running at about 36,000 CUP or 28,000 psi should hit 1200 fps. 6.3 grains of 700X should hit the number at 38,000 CUP or 30,000 psi. Note that for 700X this is near the published maximum load. For all powders mentioned, the loads are either below or within the published charge range. The recommended charges of Unique, True Blue and Tightgroup are below the published starting loads (though not by enough to be an issue). For the other powders, the starting loads are: Bullseye: 6.5 grains HP38 or 231: 7.3 grains 700X: 4.5 grains Loads using those powders should be worked up from the starting level in about 0.2 grain steps while watching for pressure signs. Every once in awhile you run into a gun that is maxed out by a starting load. I don't know what gun you have. Note that, in general, the slower burning the powder and the heavier the charge, the more muzzle flash and recoil and the less clean burning the powder will tend to be. That's why I didn't include any really slow powders for which the charge weights might be twice as heavy. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

December 5, 2014, 07:32 PM	#6
Nick_C_S Senior Member Join Date: March 21, 2013 Location: Idaho Posts: 5,523	I don't consider a 125g/357 moving at 1300 fps "low power." I mean yeah, it's fairly easy to wind up a 125g to 1300 fps (I have a number of recipes that achieve this), but that is still a pretty spunky round. __________________ Gun control laws benefit only criminals and politicians - but then, I repeat myself. Life Member, National Rifle Association

December 5, 2014, 11:02 PM	#8
Nick_C_S Senior Member Join Date: March 21, 2013 Location: Idaho Posts: 5,523	Yeah, and there's no way I'm ever going to attempt 1550 fps with Bullseye - per post #2. I like my guns - and fingers - a lot more than that. (I never aim for velocity when doing load workups anyway - but that's for another thread.) __________________ Gun control laws benefit only criminals and politicians - but then, I repeat myself. Life Member, National Rifle Association

December 5, 2014, 08:19 AM	#3
sixguns Member Join Date: March 8, 2005 Posts: 35	My factory Hornady 140gr chronograph at 1346 so a 125gr hitting 1300 fps should be easy. That's out of a Ruger GP100 4.2" barrel.

December 5, 2014, 09:13 PM	#7
sawdustdad Senior Member Join Date: August 2, 2014 Location: Virginia Posts: 484	I, too was a little perplexed by the apparent dichotomy of a "low powered/1300fps" round out of a .357 magnum. I just shoot .38spl loads, or even lower "cowboy" loads when plinking with my .357.

December 9, 2014, 02:40 PM	#10
745SW Senior Member Join Date: August 25, 2011 Location: California Posts: 776	The Speer reloading manuals I have are the number 10 dated 1987 and number 13 dated 1999. The number 13 uses the psi, transducer method. My original Speer number 10 is an early version probably with a date of 1979/1980 but can’t find it presently. The later Speer manual no longer lists the fast powders such as Bullseye and 700-X for a JHP 125 grain bullet and the older manual does not have the 38 +P at all. My decades old load of 6.0 grains of 700-X for a 125 grain JHP is lower than the window of 7.8 – 8.3 grains listed in the number 10 manual. According to the number 13 manual my 6.0 grains is 1.0 grain above 38 +P. In recent times I got data from the Hodgdon site for the 125 grain HDY XTP using 700-X. Their max load is 6.4 grains with a psi of 30.4K, that’s within the limit of 35K psi for 357 Magnum. So even by the transducer/psi method I’m OK, I think. Best to be conservative with fast powders like Bullseye, W231 and 700-X for 357 Magnum for the 124 grain bullet, IMO. This is a maximum bullet weight for a jacketed bullet for this cartridge from what I can tell.