.357 magnum rifle load advice

[6MT]

Ok fellas, I'm going to ask. I want try try 5 different charge weights in my new Winchester 1873. The bullets are lighter. They are XTP's in 125gr. The powder is H110. The barrel is a 20" with 1:18.75" twist. I know... I could do with the 158's, but I came into a lot of the lighter weight XTP's.

The brass is virgin Starline and I'm using Federal small pistol magnum primers.

The Hodgdon reloading data pages show a minimum charge weight for H110 of 21gr and a max of 22gr (rifle) for the 125gr class of bullets. Lyman regurgitates the powder manufacturer's data verbatim.

Sierra shows the min at 17.5gr and max at 19.3gr. Hornady shows a min at 10.4gr and max at 19.4gr.

Here's my plan. I loaded 5 rounds each of 16.0, 16.5, 17.0, 17.5, and 18.0gr. I know that H110 is best suited as a high end (read max charge or close to) powder. Kind of all or nothing. The cases are no where close to being full with the bullet seated.

Am I asking for some dangerous pressure spikes with the cases not being full or close to (volume wise, not charge wise)? Am I asking for a squib with the lower charge weight? How will the light duty toggle action in the 1873 react?

I need some help folks. Some guidance. I had great success with my Henry BBS in .44mag with H110. In fact I went about the load development the same way.

Or am I just over thinking this?

 

[243winxb]

I look at the 125 gr as a possible squib producer? Note Hodgdons 21 gr starting load, using your 125 gr bullet. As you seen.

But i would start with a lower powder charge, 18 grs. . Load 1 round & work up to max. Increase powder 3/10 gr at a time

Good to use a mag prime, i see you are.

 

[biggun2869]

I wouldn't load that light stuff. "Why" Personally I have landed on 2400 and I have 296 and H110 both. I just don't like the fine black stuff. It doesn't burn right in anything unless you are shooting full power loads. It has been proven though you will get max velocity from them though. If you ever go with 2400 though I don't think you'll ever go back, you can load it how you want to

 

[biggun2869]

I like 140gr bullets in the 357. I never did like the light ones and really never went for the 158s. Don't know what it would say today but way back when Masayod Abdood, not sure I spelled his name right but he was the athority in my day. The 140 was the ultimate fight stopper by FBI figures

 

[rmr]

First, I wouldn't worry about the toggle action on a new Winchester 1873. they are plenty strong enough for max published pressures on .357Mag. Second, as already stated, H110 behaves best when loaded closer to the maximum pressure specification. do NOT significantly download it.

I absolutely love the 357mag on the 1873. accurate, fast, and hard hitting!

 

[6MT]

First, I wouldn't worry about the toggle action on a new Winchester 1873. they are plenty strong enough for max published pressures on .357Mag. Second, as already stated, H110 behaves best when loaded closer to the maximum pressure specification. do NOT significantly download it.

I absolutely love the 357mag on the 1873. accurate, fast, and hard hitting!

Care to share your load for your 1873?

 

[alleycat]

H110 was always better for me in .357's,.41 Mags & .44 Mags than 296 or 2400,all of which are better suited for hotter loads.For plinking in the .357 with 158 gr. cast bullets i used Unique.Unique & other powders are better suited for light to med loads.4227 is also a good powder for the hotter loads.

 

[JSH]

I would swap the 125’s for about anything else.
I know of two of the toggle link designs that didn’t fare well with the 357’s.

It was suspected but never admitted too for years and years that H110 and 296 were one in the same, they admitted a few years back. Any difference seen were just variations in lot to lot.

 

[Twicepop]

I had a conversation with one of the technicians at Hodgdon about H110. He told me that H110 was designed to work at maximum pressures. With most cartridges using this powder, there is a very small window between the minimum charge weight and the maximum. I would also replace those Federal primers for CCIs or Winchester SMP primers, they are hotter than the Federals and should burn cleaner with the H110/WW296.

 

[hunter67]

I use 296 with 158 xtp in my rifle. It hammers Elk and deer

 

[Cochran]

I tried various combinations in my Winchester 73.Ended up with 11.0 grains of AA#9 with a 180 jacketed bullet. Mines a 24” barrel. Velocity is just over 1300 FPS. Very accurate.

It’s about the lightest recommended charge for AA#9 but I wanted an even lighter load for silhouette preferably with a cast bullet. I was referred to a high level Silhouette shooter that happens to belong to my club who has used 357s extensively. He said the best he ever got his to work was with jacketed 180s at higher velocities like I’m using. He said he had no luck with cast bullets.
I am going to try out some of the coated cast bullets just to see if they’ll come close and save me some money

 

[6MT]

The only reason I chose the 125gr XTP's over the 158's was that I got 3 boxes at a great deal. So I thought I would give them a try. And I chose H110 because I use it for .44mag in a Henry BBS.

I just got back from testing the first charge weights. As expected the lighter charge weights did not show very good accuracy. But....no squibs. Even with the 16.0gr charge, everything went bang.
Here's the speeds: 16.0gr 1718fps, 16.5gr 1782fps, 17.0gr 1807fps, 17.5gr 1860fps, and 18.0gr 1893. The 18.0gr seems to show the best accuracy. That's not surprising. I think the rifle will get more consistent and show a slight speed increase now that it has 45 rounds fired.

Here's what I decided to load: I'm going to increase the charge weight to 18.3gr to get the speed consistently around 1900fps. And because of the 1873's toggle action, I won't go any higher with the charge. After using the rifle for the first time, I can see why that action in the 1873 "could" have issues. So no hard cycling and no max charges.

I'm glad to hear of others using the lighter XTP's. Who knows? I may try the 158's when these 125's run out. And maybe I was over thinking this a bit. I was happy everything went bang and I had no issues. I shot a total of 45 rounds this morning.

Andy 6MT

 

[COLT45SA]

All the info I've seen shows barrel twist rate in the neighborhood of 1:16 to 1:18. I have a 24-1/2" barrel with a much faster 1:10 twist. How does this affect my choice of bullet weights and powders~?