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I need some suggestions to resolve a pressure problem in my .357 mag. I'm trying to develop a medium load for my Rossi 461 snubby. I decided to try Ramshot Trueblue with a Hornady 140 gr. XTP. Currently, I'm using once-fired PMC cases and a Winchester small pistol magnum primer.

As always, I began with the starting load (9.3gr.) and planned to work up from there. The problem is, I'm getting bad pressure signs (flattened primer and enlarged primer pockets) with the starting loads.

The obvious solution is to reduce the powder charge, but that means going below the listed minimum. I am going to have problems with hangfires if I do that? Any suggestions would be appreciated.

Has this Rossi ever been shot before?
Is this a New/Used handgun, has there been factory loads tested yet,etc?

My Rossi was purchased brand new about a year and a half ago. It has had several boxes of 38 special factory loads fired through it and a dozen or so full-power magnum factory loads fired through it. That's where the once-fired brass came from.

Not with that powder. They, Ramshot, list it as being recommended for very mild Cowboy Action loads. They also list it for the much milder .38 Special loads.
Don't know why you had a problem, but I do know the maximum loads for the Hornady TXP tend to be lower than they are for the Sierra 140 gr. bullets they use in their loading data. Don't know if your primers are adding to the problem. Your different cases might also add to this situation. Still, I would think that the minimum load listed for that round should not be that hot with these possible variations. But, again, loading data needs to be used with caution and as a guide only.
The other thing, of course, might be the gun itself. Is it out of spec ? I hope not.
I'd try either using the .38 Special load data or at least cut the powder charge a full grain and try it w/o the magnum primers. E

Don't mean to be insulting, but you're not putting 357 loads in 38 Special cases are you? That will produce the effect you are seeing. Had a good friend do that once.

Ummmm.. Did you clean the cylinders after the 38s? Could have fouling in throat of the chamber creating pressure spike....

I'd try a standard small pistol primer - not the magnum. The only powder I've ever had trouble lighting off is 296/H110.

Thanks for the feedback. I have cleaned the cylinders since shooting the 38's, but it can't hurt to clean them again. I definitely would never shoot a 357 load in a 38 special case. I'll try switching the primer and maybe backing the charge off a bit and see how that works.

Thanks again

Just for reference, I use True Blue at 9.2 grs. with a 158 gr. Hornady lead, swagged SWC, Starline cases and WW small pistol primers in my 3 inch, M60 Smith. I've gone up to 9.8 grs. I settled on 9.2 grs. because it shoots a little better a group and has alot more power than my old load of 6.5 grs. of Unique. Some of the cases have been loaded twice now and are no where near coming apart. No problems at all with ejection, etc. even when the gun is pretty dirty. E

What velocity are you getting in your J-frame. Is it a 38 Special or a a 357 M-60

It's a .357 Magnum, the 3 inch model. With 6.5 grs. of Unique, it clocked 925 fps. With 9.2 grs. of Ramshot True Blue, over the Hdy 158 gr. swagged SWC, it blows apart 2.5 gallon water jugs with alot more force. The bullets aren't easily seen exiting the jug or easily found as they are with the lighter load. It also kicks a good bit harder. E

Wanted to thank you guys again for the advice. I ended up switching to a Federal #100 primer, backing down to 8.0 grs. and working back up. I settled on a load of 9.0 grs. of Trueblue to keep the recoil down a bit. No signs of excess pressure .

Sab, I'm surprised nobody mentioned it, but you can sometimes experience excess pressures with loads that are too light. This usually happens with powders such as Bullseye. There are many explanations, but I'm not sure anybody knows exactly why. You shouldn't have to go with a Small Pistol Primer as opposed to a Magnum if the load in question calls for a Magnum. Of course if it doesn't...Personally, I'd stay with the exact primer specified if I was having trouble.

Glad to hear you got a load that would work.