Signs of over-pressure

[TipBledsoe]

IIRC keeping an eye on the primer condition after the shot shows sign of over-pressure if the primer appears flattened-out?

I’ve never flirted around near max load before, but I couldn’t find data for my exact combination so I’ve cautiously worked up toward max just to see where it is.

The brass looks completely fine but I’m seeing difference in the primer condition, just not the kind of difference I was expecting to see.

Revolver is S&W 331 AirLite Ti.
Caliber is 32H&R mag. Components are:

• New Starline brass
• Winchester small pistol primers
• 115 grain lead semi-wadcutter
• TiteGroup powder

I estimate max load to be about 3.5 grains of powder. The recoil is light all four recipes, but it is a very light revolver. Part of me really wants to find max load; another part of me really doesn’t want to damage the revolver or myself.

If it were you, would you try hotter loads or leave well enough alone?
May I ask you to look at the photos and comment with your wisdom please?

Photos left to right, all with moderate crimp:

1. 3.0 grains powder
2. 3.3 grains powder
3. 3.5 grains powder
4. 3.5 grains powder, bullet seated deep

Photo 1 shows all 4 brass.
Photo 2 shows all 4 brass, residue wiped.
Photo 3 shows cases 1 & 2 closer
Photo 4 shows cases 3 & 4 closer

 

[rotor]

Hornady 10th shows max titegroup load at 2.7 gr. for a 90 gr. lead bullet. Hodgun site shows max of 2.8 for 90 gr lead. How did you come to 3.5 gr. max? Heavier bullet, less load? Don't know that primer appearance is best method.
I admit to not being an expert on this.

 

[wickll]

I am not an expert on reloading pistol rounds by any means. But from my understanding, when using lead bullets you have to keep velocities much lower to prevent lead fouling in your barrel. But once again, that is just what I recall. I am not sure if that is correct.

I did see on some other forums that another factor is that it is easier to "push" a lead bullet through the barrel as opposed a copper jacketed bullet. So the key (IMO) is to find reloading data specifically for a lead bullet, if at all possible.

 

[striker55]

My first time was after firing a round the cylinder wouldn't turn, doh!

 

[GasGuzzler]

Those primers are not cratered. That doesn't mean your load is safe. How did they extract? Do they fall out of the chamber after fired? Judging by the online data of a 100 grain jacketed (lighter and jacketed both usually mean more powder than a heavier lead bullet) having a max of 3.3, I wouldn't go to much farther. Not because it's unsafe but because it's likely ineffective. I would think around 3.0 would shoot the best. In a very short barrel and with a lead bullet, you'll likely just waste powder over 3.0.

 

[Nicholst55]

Primer appearance is a notoriously poor method for attempting to judge pressures. That said, those primers do not show what one typically expects from a 'hot' load. Those primers appear to have been fired in a revolver with either a damaged firing pin tip, or an oversized firing pin hole in the breech face. It's difficult to tell much from the pictures, though.

 

[Vaquero]

Sure ain't light strikes.

 

[postal]

Nicholst55 is right. Firing pin problem.
It appears the firing pin is protruding too far, and that stretches the center of the primer. When the round pressurizes the firing pin retracts (or is pushed back) and the "thinned" center of the primer forms around the pin tip.

As for pressure, primers that indicate excessive pressure will spread much wider than that.
And looking at the outside of the casing where solid web base meets thinning wall (look at where the rings about 1/4" above the rim shows a slightly dark ring.....excess pressure will show up as little micro cracking around this area, and/or a fuzzy (non-shiny) ring around that area. Look with 10x to 20x loupe and you'll notice a lack of shine around there as pressure stretches that ring.

I've loaded 32 H&R and never had a problem but my gun is a Ruger SP 101 stainless and theyre pretty stout.

Check the pin protrusion and fix that problem first, and then try starting loads again.

In all my years of loading, the most accurate loads are almost always lower velocity. Push for speed and your group will start to fall apart.

 

[twarr1]

By the time primers flatten, you're way over pressure.