Accurate powder(s) for .38 Special/ .357 Magnum?

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J-Bar

J-Bar

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One of the cowboy action matches I attend features a bullseye style competition (one-handed) using single action revolvers, shot at close range at tiny targets. I have a Ruger Blackhawk in .357 Magnum that I will be using in this match. So I am trying to work up a load that gives very small groups at close range, 7 to 10 yards.

I will be using either 125 or 158 RNFP home cast lead bullets from Lee molds. My tests to date with Titegroup and Bullseye powder show that this revolver seems to like powder charges around 3.3 grains for both bullets. But I would like to shrink the groups more if possible.

What other powders besides Bullseye and Titegroup would you recommend trying if you wanted to put each shot through the same hole with those bullets at close range?

Thanks!
 
HP-38 definatly worth a go, also Unique and HS-6 if you push them a little faster. My .357s and .41 Blackhawk seem to tighten up a bit with stiffer...not necessarily full power...loads of the latter 2. You might also try a WC from Hornady or Speer for this specific application. Hard to beat a swaged slug for precision.

Have heard good things about WST in this application also, but no personal experience.
 
i use the lee 158 rnfp bullet in 357 mag for pistol cartridge silhouette in a marlin 1894cb with 7.0 grs of #5. runs around 1,180 fps in the 24 inch barrel. one hole groups at 40, 50, and 75 meters. opens up to 1/2 inch at 100 meters.
 
J-Bar said:
One of the cowboy action matches I attend features a bullseye style competition (one-handed) using single action revolvers, shot at close range at tiny targets.
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I’m not familiar with the rules for cowboy action. Do you need to meet a certain power factor? From what I’ve seen, you need to yell loudly, and make a lot of smoke?
You’re on the right track with Titegroup. I’ve had one hole groups with it, a 6” 686. This was loading .38’s with 125 plated. I don’t have the cast bullets you do. The fast powders work the best, I’ve worked up loads for a 138gr Bayou BNWC, using Clays, IMR Red, IMR Target, WST, and N320. They all do really well, and Clays seems to be the cleanest. Good luck!
 
lordpaxman said:
I’m not familiar with the rules for cowboy action. Do you need to meet a certain power factor?
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This is a “side match”, a warm up to the main match competition on following days. Any revolver and load that could be used in a main match is permitted in the side match. Technically there is a power factor requirement, but the loadings I listed previously meet the requirement easily.

Thanks for your list.
 
6.8 gr of BE-86 with 158gr for lighter recoil but 7.3 gr shoot the best for me with my 158gr SWC Lee tumble lube bullets. I also use 7.2 gr of Power Pistol and 7.6 grs of Power Pistol with the same bullets. These loads are light mid range loads but still may be heavier than what you are looking for.
Those are about the lightest loads I use in .357mag.
 
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• Use the 158gr bullet due to the extra rifling contact and the ability to fill the case
• Powders in the Bullseye, AA No2, W231, or Sport Pistol range will do much better. TG is too fast and will magnify any issues with case fill.
• Use matching 38Spcl brass to eliminate the errors caused by powder placement within the large volume case. And, point the muzzle at the sky before each shot.
 
I shoot 158gr cast Truncated Cone bullets in my Marlin 1894 so it's not a revolver, but I find that 3.5gr of Bullseye or 5.6gr of Ramshot True Blue gives me great accuracy at 25m. I used standard CCI pistol primers with a Starline 357mag case. Overall length is 1.600".

For those who saw the thread on the Teslong bore inspector, these groups came from my Marlin with the severe machining chatter marks on the rifling.

Edit: spelling mistakes and incorrect sight used on True Blue info.

First picture is bullseye, five shot groups with charges starting from 3.1gr up to 3.5gr in 0.1gr steps. Bottom group is 3.5gr.
20191216_203242.jpg

The 3.5gr load was shot on a second occasion once the red dot sight had been corrected. The flyer is a cold bore shot with the remaining four shots being pretty consistent.
20191216_200114.jpg


This picture is the Ramshot True Blue with different charges. Top group is 5.6gr. This was shot 6 years ago, so I would've been using a Williams rear aperture sight with the Williams fire sight front sight Simmons WTC 1.5-5x20 scope. There's no way I could've seen those small black patches so clearly even at 25m, so I must've been using that scope at the time.
2014-07-07 20.05.15.jpg
 
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Using .38 Special cases I favor a 158gr lswc bullet over W231/HP-38.

If you prefer Accurate powders try AA#2 with the same case and bullet.

In a levergun and .357 Magnum brass try a 158gr truncated bullet over AA#5 or the same W231 mentioned above. The fairly new W244 is also worth looking at.
 
Don't know if you're set on cast lead, but my 6" Colt likes a load of 3.9gr 231 under a 158gr Sierra JSP in a 38spcl case. Would have to check my notes, but I think I'm using 6.8gr 231 under the same bullet in a 357 mag case.

The 357 load is rather mild (compared to my H110 load) and the 38 load is a true mouse fart.

chris
 
Those making suggestions need to understand that the rules limit velocity to 1000 fps for pistols and a minimum power factor of 60, lead bullets only. At that range of 7-10 yards and power level it is going to be hard to tell about accurate loads, only recoil level. I would be more concerned about which bullet weight will hit POA. Are they judging group size or bullseye hits in a bullseye match? The two really go together, I expect, while the bullseye size should be the goal in group size. The usual match bullet for .357 caliber is a 148 wadcutter. I think that would be the first thing I would try and then get the best mark on the target. At 7-10 yards, shooting one handed, no rest, I would think the remaining variable on group size would be the shooter. I use 3.2 gr of Trailboss and a 158 gr lead TCFP in one of my SASS rifles and always considered it very accurate. Never tried it in a pistol since my pistols only shoot 38 LC or 38 Special.

You don't have to shoot with .357 brass. The 3.0 Trailboss I use with 125 lead for 38 Special would work fine in your .357 Mag pistols, I think.
 
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I tried to develop loads in 357 cases that were equvalent to my 38 Special standard load. My 38 Special standard load is a 158 gr L(RN or SWC) with 3.5 grs Bullseye. It chronographs at 760 fps in a typical four in revolver.

For this K frame 357, using 357 cases, it took 4.0 grs Bullseye to reach that velocity


WMwE5NW.jpg

PkVDLQq.jpg

This group is not as tight, but then, I can't see irons on a pistol anymore, but still it is good at 25 yards


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WpnNgAO.jpg

ignoring the flinches, I was surprised to find that AA#5 shot well in the 357 case, at 38 Special velocities

yBGCTA2.jpg

From what I understand about Cowboy matches, is that the competitors are looking for the lowest velocity they can get out of the round. And for that, regular pistol powders are not the way to go. Either you will stick a bullet in the barrel or, blow the cylinder with a double charge. That is why Trailboss was developed. It packs the case well. I don't have any data on Trailboss but I am sure some of the competitors have tried it, and can recommend loads.
 
I appreciate the comments and guidance.

I do not want to cause any confusion. The "side match" I am preparing for is held at a cowboy action venue, using single action revolvers and ammunition that meets SASS requirements, but is not to be confused with a regular cowboy action competition. The course of fire consists of five different paper targets, with five shots to be fired on each target within 30 seconds, shot single action one handed, at a range of about 8 yards. The scoring area for each shot is about the size of a quarter. It is quite challenging. I'm old and shaky and I know I am the weakest link in performing well. But I want the misses to be caused by me, not by controllable factors of bullet weight and powder charge. I have been running my tests with my wrist on a rest without the rest touching the gun, and it is surprising how much difference 0.1 grain of powder can make in group size even at very close range.

Based on the number of recommendations here, I bought a pound of HP38 and loaded up some test rounds using the 158 grain lead RNFP, ranging from 3.1 to 3.7 grains of powder as listed on Hodgdon's Data website. The best group was at 3.7 grains of powder:

IMG-0088.jpg

Not terrible, but not as good as the one produced with 3.3 grains of Bullseye under the 125 grain bullet:

IMG-0089.jpg

So, I think I will stick with the Bullseye loads for the moment. I am acquainted with a number of cowboy competitors who have used Trailboss and it does not appeal to me.

Again thanks to all for your input.
 
That too funny!
SASS pistol is 400-1000 FPS and min 60 PF. Seems like you’re on the right track with BE. Given your side match rules, and if you’re running such a low PF, I wouldn’t think recoil would come in to play too much so whatever groups the best is the right answer. I shot an SCSA match next to a guy who was running a .38 and I swear I could see his bullets in the air.
If you want to get adventurous, and don’t like Trailboss, VV sells Tin Star, supposedly crafted for the cowboy crowd. I was tempted to get a pound (still am) just to see how it performed.
 
lordpaxman said:
If you want to get adventurous, and don’t like Trailboss, VV sells Tin Star, supposedly crafted for the cowboy crowd.
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95% of the time I shoot black powder at cowboy matches, so I have not experimented with all the smokeless handgun powders. But I appreciate the tip!
 
J-Bar said:
I appreciate the comments and guidance.

I do not want to cause any confusion. The "side match" I am preparing for is held at a cowboy action venue, using single action revolvers and ammunition that meets SASS requirements, but is not to be confused with a regular cowboy action competition. The course of fire consists of five different paper targets, with five shots to be fired on each target within 30 seconds, shot single action one handed, at a range of about 8 yards. The scoring area for each shot is about the size of a quarter. It is quite challenging. I'm old and shaky and I know I am the weakest link in performing well. But I want the misses to be caused by me, not by controllable factors of bullet weight and powder charge. I have been running my tests with my wrist on a rest without the rest touching the gun, and it is surprising how much difference 0.1 grain of powder can make in group size even at very close range.

Based on the number of recommendations here, I bought a pound of HP38 and loaded up some test rounds using the 158 grain lead RNFP, ranging from 3.1 to 3.7 grains of powder as listed on Hodgdon's Data website. The best group was at 3.7 grains of powder:

View attachment 890525

Not terrible, but not as good as the one produced with 3.3 grains of Bullseye under the 125 grain bullet:

View attachment 890526

So, I think I will stick with the Bullseye loads for the moment. I am acquainted with a number of cowboy competitors who have used Trailboss and it does not appeal to me.

Again thanks to all for your input.
Click to expand...

I don't know if you are prohibited from using 148 LWC's or 148 lead hollow base wadcutters, but they were the standard of accuracy and low recoil in 38 Special revolvers used in 2700 Bullseye pistol competition. The "standard" load was 2.7 grs Bullseye plus or minus in a 38 Special case. Looking at my data, out of a four inch revolver the bullet is going 700 fps. Different lots will produce slightly different velocities, and that is important for Bullseye competitors as they shoot at 25 yards and 50 yards. If the bullet becomes unstable before 50 yards, its not a good load. I don't know how sensitive this load is to velocity variations but considering how far back it dates, probably not sensitive to 0.1 to 0.2 variances in charge levels. Faster is probably better at 50 yards all things being equal. This load is accurate out to 50 yards, in a well built revolver I have heard groups of two inch diameter at 50 yards.
 
J-Bar said:
95% of the time I shoot black powder at cowboy matches, so I have not experimented with all the smokeless handgun powders. But I appreciate the tip!
Click to expand...
Well, the 30 second time allowance could rule out trying to shoot through all the smoke. It is now understandable why a BP shooter would be reluctant to get too involved in smokeless inventory.
 
RealGun said:
Well, the 30 second time allowance could rule out trying to shoot through all the smoke. It is now understandable why a BP shooter would be reluctant to get too involved in smokeless inventory.
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True, smoke clouds can be an issue. Also, varying blackpowder charges in a brass case would require playing around with fillers for volumes smaller than a full case load, and I just do not want to mess with fillers. I could tweak the powder charge in a percussion revolver much more easily, but that would require reloading on the firing line while my fellow competitors are waiting on me. I actually did that once many years ago in this same event, but I found the urge to reload quickly to be distracting.
 
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