Q re loading LSWC for 357 magnum

[kpmtns]

I have been reloading various calibers for years, and have extensively loaded 357 magnum loads with jacketed bullets. Recently, I loaded up a few 357 magnum rounds using Laser Cast 158g hard cast LSWC bullets to try something different. Cartridge length and OAL are perfect on them, but they won't chamber in my 686 or my GP100 or my Python because it appears the shoulders of the WC part of the bullets interfere with the chamber throats. I then loaded up a round using a very similar 158g LSWC from Colorado Bullet, and had the same problem.

Are you guys aware of any LSWC that have shorter shoulders so they can be loaded in normal length 357 brass? Or, do you recommend that I trim the brass down for use in these loads, and reduce the charge a bit to compensate for the decreased volume? I don't want to load up 38 special brass to higher pressures because I'd like to avoid bullet jump in the 357 magnum chambers. Any advice appreciated. Thanks.

 

[acl864]

I haven't loaded those particular bullets but I've loaded lots of 158 LSWC bullets in 357 Mag cases without a problem. You may be having an issue with carbon rings left in your cylinders from shooting 38 Specials.

 

[Jellybean]

You don't mention what type of equipment you are loading on.

If you are seating and crimping in the same step, you may be bulging the brass slightly near the mouth. If this is the case try doing this in two seperate steps on a couple of test rounds and see if it helps.

 

[kpmtns]

ACL--I don't think rings are the problem, as the chambers in the 686 have been freshly cleaned and look polished/shiny. I'll run a bronze brush through them again, though, just in case and report back.

Jelly--I am using an all-RCBS set up, and seating and crimping at the same time. (Which I realize isn't optimal, but hasn't caused any issues until perhaps now.) You may be on to something there that I had not thought of. Let me do a test and see if that does it. I'll report back.

 

[bnitch]

Try a lee factory crimp die, it may resize the area that is too large in the neck. The hard cast don't size down very much when crimped. Are you crimping them into the grove in the bullet?

 

[Skip Sackett]

You have two solutions.

They are: Seat the bullet to the correct OAL and get smaller bullets.

What do that bullets measure at the last driving band? A .001" reduction will make all the difference in the world. It may also cause some significant leading. A LFCD isn't going to do anything to the last driving band because it isn't in the case, which brings my to my next point. Seating over the end of the last driving band.

In the early days of the 357Mag this problem was amplified even more by the short cylinders on the "N" frame revolvers. It seems that Keith and the 358156(?) bullet had too long of noses for them. The Keith was seated and crimped over the last driving band, the 358156(?) bullet has two crimping grooves. One to make the bullet stick out of the 38spl case a little more and one so that more of the bullet was in the case for 357Mag.

Do you have any pictures of your loads?

 

[canoe on the yukon]

I have been reloading various calibers for years, and have extensively loaded 357 magnum loads with jacketed bullets. Recently, I loaded up a few 357 magnum rounds using Laser Cast 158g hard cast LSWC bullets to try something different. Cartridge length and OAL are perfect on them, but they won't chamber in my 686 or my GP100 or my Python because it appears the shoulders of the WC part of the bullets interfere with the chamber throats. I then loaded up a round using a very similar 158g LSWC from Colorado Bullet, and had the same problem.

Are you guys aware of any LSWC that have shorter shoulders so they can be loaded in normal length 357 brass? Or, do you recommend that I trim the brass down for use in these loads, and reduce the charge a bit to compensate for the decreased volume? I don't want to load up 38 special brass to higher pressures because I'd like to avoid bullet jump in the 357 magnum chambers. Any advice appreciated. Thanks.

When you say the overall length is "PERFECT",what are you basing that on?If you mean that the length does not exceed the maximum overall length for the cartridge,the cartridge overall length may be excessive for that bullet.Some cast bullets actually need to be seated until the case can be crimped over the shoulder rather than in the crimp groove.I'm not familiar with that particular bullet but I'd investigate from that angle.

As an aside,non-jacketed bullets are best seated and crimped in seperate operations.

 

[kpmtns]

I am crimping the case properly in the groove, so I think the mouth bulge idea may the the problem. If I can't solve it with my current die setup, I'll get a Lee and try that.

As to length, I just meant the OAL is within spec based on the reloading manuals for similar bullets, but not the exact bullets, as I don't have data from or for Laser Cast or Colorado Bullets (which has no data available). Based on the location of the crimping groove on these bullets, there would appear to me to be no option on changing the length other than shortening the brass below the "trim to" specification. It's too bad I don't have a .38 revolver to see if the bullets loaded in .38 special brass are too long for the chambers. Obviously, they fit fine in the .357s.

 

[canoe on the yukon]

If you're certain that the COAL is not excessive with that particular bullet,it's possible that you are belling the case mouths too much,crimping excessively or both.

 

[kpmtns]

Smith Crazy--I guess I could seat it over the front driving band, and reduce the load a bit. I have no idea what the size of the front driving band is. I was thinking more of isses with length than diameter, but I guess both are at play here. I'll measure it and see. It must be a hair larger than the throats to cause a problem regardless of the length.

 

[bnitch]

1.585 is the OAL min. for Oregon Trail's bullet but there is only really one place to crimp it to and that is the crimp grove on the bullet.

 

[Steve C]

OAL is determined by the crimping groove in these types of bullets. Its highly unlikely that the problem is the bullet shoulders, it more likely you are binding in the chambers either at the mouth of the case or at the base.

Pythons and Colts in general have pretty tight chambers and short cylinders and if the case isn't fully sized and there's any bulging at the base a round may not chamber. If you don't crimp and take the case belling or if you don't expand properly and bulge the case when seating the bullet you can get problems at the case mouth end. Using a Lee Factory Crimp die will iron out any of these bulges with its maximum size post sizing ring but its something that generally isn't needed unless you are using very thick brass or exta large sized bullets.

I've used both the bullets brands you've listed and many others and when I've had problems with chambering its been one of the above issues that is easily fixed.

Your .357 mag round crimp should look like this.

 

[Skip Sackett]

1.585 is the OAL min. for Oregon Trail's bullet but there is only really one place to crimp it to and that is the crimp grove on the bullet.

No, that's not true. The original diagram for the 357mag shows the crimp OVER the end of the last driving band. Kind of like a 38spl with WC bullets.

kp,
Call me Skip, please. Will the bullet chamber at all? I got from you original post that they would go in all but the last little bit. Seeing as the chamber on a 357mag is pretty much straight I figured the bullet's driving band was trying to enter the throat. If that is what is happening follow what I said at the start. If not, then it is possible that you have over crimped and caused a bulge in the case at the crimp. If that is the case the LFCD will help but that isn't the right answer. The right answer at that point is to set your crimp die up properly.

Again, pictures, if possible.

 

[kpmtns]

My rounds drop in easily until I get to the last 1/8" or less (I didn't measure it last night). So, it i spossible that there could be a problem with the rear bulging, but I full-length sized this brass, and in .38 Special loads, the rounds drop right in. I will test out the bulged base hypothesis with a sized piece of brass tonight and report back. Whew--I have a lot of reporting to do! I sincerely thank all of you for helping me out so far, and keep the good ideas coming.

 

[Skip Sackett]

My rounds drop in easily until I get to the last 1/8" or less (I didn't measure it last night). So, it i spossible that there could be a problem with the rear bulging, but I full-length sized this brass, and in .38 Special loads, the rounds drop right in. I will test out the bulged base hypothesis with a sized piece of brass tonight and report back. Whew--I have a lot of reporting to do! I sincerely thank all of you for helping me out so far, and keep the good ideas coming.

Have you shot 38spl with lead bullets in this firearm before?
If so you have a carbon ring built up in the cylinder that has to be removed. If your sizing die is touching the shell plate when you resize, there really isn't much more you can do. Besides, if a 38spl will go in, that portion of the case is worked on the exact same way by the sizing die.


I'll attach a picture for you to see what I meant in my previous posts.

 

[nitesite]

I wish I could tell you how to fix it. But I'll add a comment that I have loaded lots of Laser Cast 158-gr LSWCs in .357 cases and don't have the same problem in my 686, Security Six or Model 28-2.

Those same cartridges did, however, fail to fully chamber in a friend's Python.

Do your case mouths actually touch the front driving band or can you still see some of the crimping groove?

 

[kpmtns]

Skip--I got it. I'll check the rounds carefully this evening. I have not shot .38's in lead in this revolver, but I just cleaned all signs of fouling out of the chambers with a bronze brush last night, so I don't think the carbon ring is it. The bulge in the case mouth may be the culprit since I seat and crimp in one operation.

Nitesite--I believe the case mouth may be a couple thousanths short of the front driving band, but the rounds hit resistance more than that distance from being completely seated in the chamber.

I need to take a careful look at these rounds tonight. I used the rounds in a GP100 I used to have, and only had a problem with a few of them. Those few would fully seat in the chamber if I nudged them, but they would not drop in like JHP's would.

 

[kpmtns]

I took a look at the rounds with good light, and tried loading them, and found the problem. There was a slight bulge at the base of a few of the rounds. I'm not sure why this wasn't corrected with full length resizing, other than to say that the die must not have been screwed down all the way. In looking and a bunch of reloads, only a few had the bulge, and those were in the batch done with the LCSW bullets. So, thanks all for the help!

 

[Nightowl]

I have not reloaded .357 rounds for some time, but I had that problem loading .357 brass. Do not really know why, even with full length resizing die set as far as possible, bumping the shell holder. Never had a problem with .38 Spec brass.

Glad you found the problem.

 

[kpmtns]

Richard--That's what I'm afraid of. I'm not sure why all the .357 brass wasn't affected, especially given my habit of making sure the die hasn't backed out every 10 rounds or so. I think it may be because the carbide ring is set up a bit from the end, and may be above the bulge in some cases, though I can't be sure. I am going to mess around with the settings and see if I can get the bulged brass into spec.