357 Magnum Light Loads - Good or Poor Choice

[03lover]

I am a bullseye shooter and enjoy using cast boolits and light to mid range loads. I am also very particular about accuracy. I like to shoot my 357 magnums in addition to my 38 specials and many other handgun calibers.

The problem I have with the light to mid range loads in the 357 magnum is consistent accuracy. I was getting groups with great clusters and a few shots out of the group.

I decided to start chronographing all my load testing. I found the loads that used less than 75% of the available space for powder to be the problem. Loads using 50% or less available space were much worse. Powder position is the problem.

I performed hundreds of tests with many different powders, primers and bullets. I fired with the powder to the rear and powder to the front to see what the difference may be. I found an average of 100 fps to 250 fps changes in velocity with the powder to the rear always the higher velocity. Extreme spread also varied greatly. The groups fired varied the point of impact on the target at only fifty feet, from around 1" to over 2" powder to the rear vs powder to the front.

I have tried many powders said to be less position sensitive, but not much less.

I realize plinker type shooters are probably not interested in this, but if anyone is being troubled by groups that are pretty good except for a few flyers, you may want to consider this powder position may be the problem.

I haven't found a good fix for the powder position problem with light to mid range loads in the 357 magnum. If I make an effort to position the powder to the rear before firing, groups are great. This isn't always possible. Fillers can work but add to the time and cost of reloading.

The bottom line is if the shooter reloader is aware of the problem, avoiding the worst extremes of powder position will tighten the groups or increas the number of hits.

[44man]

Longer brass was never designed to shoot .38 loads with the same powders. If you want light loads in the .357, find a powder that fills the case more. No need for mag velocity but powder choice is what you need to look at.
Even the .38 with the wrong powder will show the same results.
The boolit is important, a wad cutter in the .38 is deep in the case so a pinch of Bullseye is far different then with a Keith.

[jameslovesjammie]

Did you test Trailboss? Trailboss is a revolver's best friend with low to mid power loads.

[L Ross]

Trail Boss may solve your problem.

Duke

[03lover]

All good points and Trail Boss is the bulkest powder for the job.

I am well aware of the problems using 357 magnum for light loads, but I keep hoping I can find the magic combination. I am sticking with the 148 grain wad cutter and HBWC for the light loads to fill as much of the free space as possible.

I tried Trail Boss once, going from 3.2 gr, to 4.0 gr. but grouping was a bit erratic and velocities ran from 753.9 fps to 779.7 fps. One group tight the next opens up with the next powder charge tight again and so on. With small increases with each powder charge I expect to see some kind of regular progression of groups getting better or worse and the five powder charges of Trail Boss I tried made choosing the best difficult. I don't like to see erratic with small increases of powder because the slightest variation can mess up the group sizes.

The trail Boss is worth another try using three different primers to see if one brand works better than another. The velocity range I was in with the Trail Boss was good for the HBWC. I am not sure lower or higher will be better. If all else fails, I can try.

[zxcvbob]

Great light-to-mid .357 Magnum load: 148 grain DEWC and 4.5 grains of Red Dot or Promo. Crimp in the crimp groove, not over the top (OAL will be somewhere around 1.35") I just loaded a batch yesterday.

[paul h]

Can't provide a solution that's worked for me, but it sounds like a good explanation why my 357 will shoot 3 or 4 into 1 ragged hole at 25 yds and throw one of two shots an inch or so out from the group. Also explains why my 480 shoots steller groups will full patch loads, but trying to back off loads to target levels i.e. 700 fps has resulted in mediocre accuracy.

The long and the short of it is that I believe too much air spare results in inconsistant ignition and hence inconsistant accuracy.

[white eagle]

ever thought about some dacron filler
will keep powder where you want

[btroj]

Why shoot the light loads in magnum brass? That is what special brass is for.
If I use magnum brass then I load Irwin magnum loads. Low to mid level loads are put up in special cases.

Seems to me ou are looking for a solution to a problem that need not exist.

[Thumbcocker]

Another vote for 4.5 of red dot.

[zxcvbob]

Why shoot the light loads in magnum brass? That is what special brass is for.
If I use magnum brass then I load Irwin magnum loads. Low to mid level loads are put up in special cases.

Seems to me ou are looking for a solution to a problem that need not exist.

There's a pretty big step up from top-end .38 Special loads and starter .357 Magnum loads.

[btroj]

I don't see the step as being that large. Look at Hodgdons data. 38 +P goes 950 fps with a 158 jacketed bullet.. 357 start loads begin around 1000 fps for same bullet depending on powder.

use the old 38/44 data and we get even closer to 357 start velocities in a special case.

[zxcvbob]

I don't see the step as being that large. Look at Hodgdons data. 38 +P goes 950 fps with a 158 jacketed bullet.. 357 start loads begin around 1000 fps for same bullet depending on powder.

use the old 38/44 data and we get even closer to 357 start velocities in a special case.

I actually put that wadcutter load in .38 Special brass, but I load them to .357 lengths. They look kind of silly with the wadcutter bullet sticking halfway out the case, but they will not chamber in any .38 Special that I've tried and that's a good safety feature.

I used to load 38/44's for my Marlin and paint the case heads with a red Magic Marker and write "Danger! Rifle Only" on the box, but I decided after I'm gone some idiot future grandkid of mine might get ahold of them and shoot them in a pot metal RG revolver or something. I guess that's still a possibility with the long wadcutters, but only if the gun has the throats bored out to get rid of the step at the start of the throats -- or he hammers them into the chambers.

It's safest to use .357 brass for any high pressure loads.

[Salmoneye]

Another vote for 4.5 of red dot.

+2

:drinks:

[got_lead?]

OK, so here's a suggestion, take it or leave it. Seat deeper in the case. With a revolver, there's no problem seating Nagant style, with the boolit shoulder below the case mouth. I use this method for 120 grain boolits in my S&W model 52, which requires that any boolit is seated below the mouth. And this load of 2.8 gn bullseye behind a 120 grain TC shoots like a target pistol out of my snubby as well. Seating deeper will increase powder efficiency too, just don't seat too deep for the boolit weight. Consider the length of the cartridge to be from the rim to the nose of the boolit, wherever it's seated, as long as the COL and the load are copasetic, your'e golden.

http://i1187.photobucket.com/albums/z398/1homebrewed/PICT0004c.jpg

[btroj]

I only own modern, strong 357s so safety factors aren't an issue for me.

I generally have 2 levels of 38/357 loads. I shoot mostly low end 38 special lands or full on mag loads. I don't have much need for middle ground loads.

[03lover]

Lots of good suggestions. Thanks.

I will have to try the 4.5 gr. of Red Dot and deep seating the bullets.

My Red Dot is about 55 years old and hasn't been used since the mid 60's. I'll check it out and if it still looks good I will load ten rounds to see how it performs in a 5-1/2" barreled Ruger. I may have to pick up a small can for load developement.

I like the idea of deep seating the bullet over shooting 38 Spl. in a 357 magnum. Same amount of jump but the bullet will be better supported before entering the cylinder throat. A note of caution is needed here. Because the brass gets thicker toward the base a person wouldn't want to seat a bullet too deep or it will be undersized by the brass.

It is easy to determine where the top of the powder charge is and that can be where the base of the bullet should be to eliminate powder position problems. I will report the results of my testing when completed.

[zxcvbob]

I will have to try the 4.5 gr. of Red Dot and deep seating the bullets.


:shock:

What bullet are you talking about "deep seating"? 4.5 grains is a lot of Red Dot, if you stuff 158's down in the case with the nose flush you are likely to blow yourself up. With 125's it's probably OK.

[subsonic]

I've had good luck with 700x in .38's in a .357. Generally, people will say that you'll get better accuracy with a .357 case in a .357 chamber, but I wouldn't take that as a hard and fast rule.

I have some .38s loaded with 148gr Lee wadcutters over 3gr of 700x and the last group I shot (6 shots) at 25yds was right at 3/4" from my 686 .357. All the other shots (while sighting in) were right where they should have been from the adjustment. I need to experiment further, but maybe this will give you some direction and hope.

[rhbrink]

+2

:drinks:

+3

Richard

[Salmoneye]

Please do NOT deep seat with the 4.5gr Red Dot...

I never suggested any such thing, and would not...

[03lover]

:brokenimaAccuracy is something we all talk about but what we consider accurate can vary like crazy. I have my idea of what I consider accurate and I prefer to see very good ballistic uniformity with that accuracy.

What I am trying to say is the load I consider to be best is not only accurate but the extreme spread is low. Also, the load is not powder position sensitive. I Always perform the following test. Fire ten rounds by pointing the loaded handgun straight down, slowly raise to level and fire. Do the same for ten rounds. Firing over a chronograph provides important data and a good rest aids in accurate shooting. Then fire ten more rounds by pointing the handgun straight up, slowly lower to level an fire each ten rounds this way.

What I often find with this test of loads of powder charges that use less than 75% to 85% of the available space is two things. First the chronograph indicates the powder forward are always 75fps to 250fps slower, especially when the powder charge uses less than 50% of the available space. Next I see the point of impact vary vertically on the target. Sometimes by as much as 1-1/2" at fifty feet. That is enough to mess up accuracy if firing is done with a lot of movement between shots.

I started to persue this problem after a day of load testing was indicating many of my first shots of a five shot string were lower in velocity and out of the group. I realized my first shots followed loading my revolvers with the gun pointed down and raised to level in the pistol rest on the bench. That put the powder forward for the first shot. The next four rounds were fired with the gun reaimed and powder wherever the recoil left it. The last four rounds had the powder positioned in the same place but the first round was very different.

I think most of us see any number of groups we shoot with one or two rounds out of the group. The ten shot groups in a nice tight cluster can and do occur with loads that may actually have some powder position problems, it all depends on how consistent the shooter is with positioning the gun for each shot.

Before you beat me up for being so nit picky, I have been retired for twenty years. I love shooting and reloading in persuit of perfection. Do I get perfect loads, not too often, but I get a lot of darn good ones, loads without the things that cause me to look for a new excuse for less than desirable accuracy. It is a great reason for loading more and firing more and keeps me busy doing what I like most.

Powder position sensitivity is one of the biggest reasons for less accurate loads and should be avoided whenever possible.

[Wally]

:brokenimaAccuracy is something we all talk about but what we consider accurate can vary like crazy. I have my idea of what I consider accurate and I prefer to see very good ballistic uniformity with that accuracy.

What I am trying to say is the load I consider to be best is not only accurate but the extreme spread is low. Also, the load is not powder position sensitive. I Always perform the following test. Fire ten rounds by pointing the loaded handgun straight down, slowly raise to level and fire. Do the same for ten rounds. Firing over a chronograph provides important data and a good rest aids in accurate shooting. Then fire ten more rounds by pointing the handgun straight up, slowly lower to level an fire each ten rounds this way.

What I often find with this test of loads of powder charges that use less than 75% to 85% of the available space is two things. First the chronograph indicates the powder forward are always 75fps to 250fps slower, especially when the powder charge uses less than 50% of the available space. Next I see the point of impact vary vertically on the target. Sometimes by as much as 1-1/2" at fifty feet. That is enough to mess up accuracy if firing is done with a lot of movement between shots.

I started to persue this problem after a day of load testing was indicating many of my first shots of a five shot string were lower in velocity and out of the group. I realized my first shots followed loading my revolvers with the gun pointed down and raised to level in the pistol rest on the bench. That put the powder forward for the first shot. The next four rounds were fired with the gun reaimed and powder wherever the recoil left it. The last four rounds had the powder positioned in the same place but the first round was very different.

I think most of us see any number of groups we shoot with one or two rounds out of the group. The ten shot groups in a nice tight cluster can and do occur with loads that may actually have some powder position problems, it all depends on how consistent the shooter is with positioning the gun for each shot.

Before you beat me up for being so nit picky, I have been retired for twenty years. I love shooting and reloading in persuit of perfection. Do I get perfect loads, not too often, but I get a lot of darn good ones, loads without the things that cause me to look for a new excuse for less than desirable accuracy. It is a great reason for loading more and firing more and keeps me busy doing what I like most.

Powder position sensitivity is one of the biggest reasons for less accurate loads and should be avoided whenever possible.

I use such loads in my .357 Magnums...use a poly filler and all will be well for you.

[03lover]

I loaded up fifty rounds of 148 grai HBWC's using the Hornady bullet. Twenty five rounds had Remington 1-1/2 small pistol primers and twentry five had Winchester small pistol primers.

Now this test is with my Ruger 357 magnum Bisley, 7-1/2" barrel, my batches of primers, powder and brass is Winchester. Also I noted there was very little space left between the top of the powder and base of the bullet, so this test simply blew my mind. I didn't anticipate any change from powder to the rear to powder forward. WRONG!!

First five rounds with 4.5 gr. of RD and Remington primers and powder to the rear, blew the skirts off two of the bullets. The the second five with powder forward were OK and the group was nice.

Then I fired five rounds with the Winchester primers and powder to the rear. Like the Remington primed rounds, two of the five blew the skirts off the bullets. The second five with Winchester primers and powder forward acted OK but the group was strung out a little vertically. The Winchester primers were a little warmer than the Remington as noted by brass expansion and resistence to extraction.

The Winchester small pistol primers have always been a bit warmer with all the powders I have tried them with giving somewhat higher velocities.

I will have to repeat the test, but drop the powder charge to 4.0 grains.

[zxcvbob]

I loaded up fifty rounds of 148 grai HBWC's using the Hornady bullet. Twenty five rounds had Remington 1-1/2 small pistol primers and twentry five had Winchester small pistol primers.

Now this test is with my Ruger 357 magnum Bisley, 7-1/2" barrel, my batches of primers, powder and brass is Winchester. Also I noted there was very little space left between the top of the powder and base of the bullet, so this test simply blew my mind. I didn't anticipate any change from powder to the rear to powder forward. WRONG!!

First five rounds with 4.5 gr. of RD and Remington primers and powder to the rear, blew the skirts off two of the bullets. The the second five with powder forward were OK and the group was nice.

Then I fired five rounds with the Winchester primers and powder to the rear. Like the Remington primed rounds, two of the five blew the skirts off the bullets. The second five with Winchester primers and powder forward acted OK but the group was strung out a little vertically. The Winchester primers were a little warmer than the Remington as noted by brass expansion and resistence to extraction.

The Winchester small pistol primers have always been a bit warmer with all the powders I have tried them with giving somewhat higher velocities.

I will have to repeat the test, but drop the powder charge to 4.0 grains.


Drop all the way to 3.0 if you insist on using hollow-based bullets. 4+ is a high pressure load and of course it blew the skirts off. (I thought I said DEWC.) You can't safely load a midrange .357 Magnum with a HBWC, whether you loading it forward or backwards.

[1Elkhunter]

.357? light or heavy, don't really matter when you're shootin' crows... now the .45 Colt? Now we're talkin! Step up!

[1Elkhunter]

OK, so here's a suggestion, take it or leave it. Seat deeper in the case. With a revolver, there's no problem seating Nagant style, with the boolit shoulder below the case mouth. I use this method for 120 grain boolits in my S&W model 52, which requires that any boolit is seated below the mouth. And this load of 2.8 gn bullseye behind a 120 grain TC shoots like a target pistol out of my snubby as well. Seating deeper will increase powder efficiency too, just don't seat too deep for the boolit weight. Consider the length of the cartridge to be from the rim to the nose of the boolit, wherever it's seated, as long as the COL and the load are copasetic, your'e golden.

http://i1187.photobucket.com/albums/z398/1homebrewed/PICT0004c.jpg

I sense a squib coming! Feel the force Luke!

[03lover]

Sorry. I did misread the DEWC and was thinking HBWC that I have been working with.

I am not insisting I use the 148 gr. HBWC, I simply have (2500) of them to work with. I have some DEWC's also, so I can do some testing with them also.

Later.

[zxcvbob]

Use the HBWCs for light .38 Special target loads. That's what they excel at. You can load them in .357 Magnum cases, but you still have to use .38 Special load data (plus a extra about .1 grain of powder) If you try to load them hot you will either blow the skirts out (as you found), or blow the centers out and possibly stick the half a bullet in the barrel as an obstruction for your next shot.

DEWCs rock. You can use them in anything from light target loads to full-power magnum loads. In the target loads they /may/ not be as accurate as the HBWCs, and in full power loads you can't get as much power as with SWC's because you have to seat them deep in the cases so you lose case capacity.

[Char-Gar]

Some years back there was a blow up by a fellow loading the old standard load of 2.7/BE over a wadcutter. The NRA had H.P. White labs run some tests on double charge and deep seated bullets and this is what they got. I gather that deep seating alone will at least double the pressure. I would never deep seat a bullet. Click on pic to enlarge.

[subsonic]

That's a cool test Char-Gar. Thanks for sharing that! Obviously a slower powder would be a little less sensative. I wish they would have tested it with that wadcutter crimped in the crimp groove as well.

Pressure signs are still pressure signs, regardless of seating depth.

[44man]

So important, safe or totally dangerous.
Wonderful post Char-Gar.

[uscra112]

Please do NOT deep seat with the 4.5gr Red Dot...

I never suggested any such thing, and would not...

AMEN, AMEN, AMEN. That charge with a flush seated 158 grainer - well, Quickload thinks it's a 60,000 PSI load.

2.5 grains Red Dot for flush seated is more like it. BTW I do that myself, but I use Bullseye.

[Ola]

Ok, this is an old thread but just in case someone needs the info: 4,4 grs of Vihtavuori N310 is a great LIGHT load for 150 gr boolits. This N310 load was found in old LAPUA manual from the time Lapua was still making lead revolver bullets for .357. It doesn't exist in the current VV data.

The 4,4 gr load is mild, but consistent and accurate in S&W 586 6" and T/C 10". (I use it up to 100 meters. It feels almost like shooting a .22LR but it has enough power to topple the 1/2 size rams.)

N310 burns so easily that there is no need for dagron or other fillers. I load them with Dillon 650, just like any other 357 mag load. The only difference is that I do not grimp the bullets: there is no need for it and the accuracy is better.

One more thing: IF you accidentally make a double charge, it SHOULD NOT be a "bomb" in a modern revolver or pistol.

[sargenv]

Wondering why not use shorter brass instead of seating bullets deep? Lots of ICORE shooters load the 38 short and long colt, or something in between (self trimmed 38 spl cases to 0.900"). That would eliminate the issue of too much space in the case.. If you are worried about ringing the cylinders, well, I know many shooters with over 100,000 rounds through their guns with no issues.. (usually 627's).

[rogerstg]

Have you tried Titegroup? It doesn't seem to care about it's position in the case.

[Outpost75]

A very accurate shooting field load I use in the .357 is the Saeco #348 bevel-based, double-end wadcutter, seated and crimped in its normal crimp groove, with the beveled front band outside the case, in .357 brass with 10 grains of Alliant #2400. This leaves very little airspace in the case and gives about 1000 fps in my 4-5/8" Ruger Blackhawk and is both accurate and effective on game. Power level is a bit more than .38 Special +P, but less than a full-charge .357 Magnum. The DEWC bullet cast of wheelweights, loaded as-cast and unsized, lubricated with Lee Liquid Alox and then run through the Lee Factory Crimp die does not lead, but is more accurate than match .38 Special wadcutters fired in the .357 chambers.

A charge of 5 grains of Bullseye or 6 grains of PB similarly loaded in .357 brass also shoots well.

[siamese4570]

To continue on "got_lead's" deep seating idea. I do that in a 357 handi rifle for my cat sneeze loads. I intentionally did it to increase the pressure to get the 158 gr rf out of the barrel. Of course I'm only using 1.5 gr Bullseye. Sound like a pellet gun. Chrono's at about 600 fps. got a lot of time on my hands.
siamese4570