.357 swaged hollow base WC in a .358 cylinder chamber

[porkchop]

I'm new to casting and I'd like to know if the swaged bullets I bought were the wrong size. A friend of mine said I should buy swaged hollow based wadcutters because they are more accurate than my cast wad cutters.
So I bought them from a company that sells a lot to the bullseye shooters which I do enjoy. The problem is leading in the cylinder, forcing cone , and first 1" or so of my barrel. I talked to the bullet company owner and he said the bullets are .357" and worked fine for other shooters. I have a sw 686 4" barrel all chambers are sized to .358" and I have a 11 degree forcing cone cut in it. To me a good lead bullet set up.
I normally shot 3 grains of BE with cast wc and they work good. I don't think those swaged wc are expanding enough, should they have been .358" or something. Is there anything I can do to make them bigger. I measured them with a dial caliper and my micrometer and they are .357"
I was using .38 special cases and also tried .357 cases with 3.3 grains BE with the same results.
I love this forum, and thanks for any help,
Stan

[Gofaaast]

Try a little heavier crimp if you haven't already with 2.8 grains of BE in 38 special brass.

[Outpost75]

Shooting hollowbased wadcutters loaded in .357 chambered revolvers is NOT a good idea, because, depending upon bullet hardness and cavity geometry of the base, the skirt will inflate while the bullet is transitioning the unsupported gap between the case mouth and the ball seat of the .357 chamber.

When I was at FBI National Academy back in the 1980s, I personally observed dozens of instances where trainees doing so managed to score 80 hits on a 60-shot tactical revolver course! Yes, the bullets were coming apart!

No the guns weren't hurt, but the cylinders were sure leaded up.

If you want to shoot wadcutters for best accuracy in a .357 revolver, load them in .357 brass or use SOLID BASED or double-end wadcutters such as the Saeco #348 loaded in .38 cases for use in your .357 gun! I load 3.5 grains of Bullseye in .357 brass and 3.2 grains of Bullseye in .38 brass with the Saeco bullet shown below.

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[porkchop]

Outpost, i never thought about the gap, especially with wadcutters. Would the fact that my hollow base wadcutters are .3575" and my chambers are sized to .358" make a difference also, I haven't had any skirts blow off yet.
I'll try 357 cases and try 3 grains of bullseye. what type of crimp would you use roll or taper and what diameter would you crimp to. The reason I'm asking what type crimp is because these are hbwc and swaged.

I'll say a softer lead likely (6 bhn), also the cavity is about .10" at the skirt edge and.250" deep. It's kind of shaped like a .308 bullet, I can put in the cavity about .250".

I was seating them flush but maybe I should go out to the top lube groove also.

If you can think of anything else I sure would appreciate it.

Thank youmuch, Stan

[Outpost75]

Outpost, i never thought about the gap, especially with wadcutters. Would the fact that my hollow base wadcutters are .3575" and my chambers are sized to .358" make a difference....would you use roll or taper and what diameter would you crimp to. The reason I'm asking what type crimp is because these are hbwc and swaged....maybe I should go out to the top lube groove also. If you can think of anything else I sure would appreciate it. Stan

When the ammunition manufacturer's and the FBI lab investigated the failure mechanism they used finite element analysis to explore the effects of chamber pressure versus bullet travel in the cylinder and in transition into and out of the barrel. With a fast burning powder such as Bullseye, peak pressure occurs approximately at the point where the bullet base clears the case mouth. With soft alloy a bullet only 0.001 or so smaller than the ball seat will be quickly upset to fill the available space within its containment by the case wall and chamber.

In the case of firing a .357-.358 bullet in a .357 chamber, the soft skirt is upset to conform to the .379-.380" diameter of the unoccupied length of the .357 chamber, and depending upon cavity geometry and the presence and locations of grooves or cannelures on the bullet, the skirt may be deformed into the 15 degrees basic mouth of the .357 chamber in proximity to the ball seat entrance. The deformed skirt is momentarily delayed while the forepart of the bullet continues forward under gas pressure. In factory HBWC bullets the deep, rectangular grease grooves acted as stress risers, resulting in a ductile fracturing mechanism as the elastic limits of the elongating bullet were exceeded.

After these results became available at least one manufacturer changed eliminated knurled cannelures from its HBWC wadcutter bullets and went to a light surface knurling and a dry film lubricant which covered the entire surface of the bullet. The firearm manufacture, with whom I was employed at the time, and who was producing revolvers for the government, changed the transition angle from the chamber mouth into the ball seat, reducing the angle from 15 degrees, Basic to 6 degrees, basic, to mitigate against the "nail head-ductile fracture" bullet failures.

For handloaders the key is to use HBWC bullets in cases of proper length for your revolver chambers. If you must use .38 Special wadcutters in .357 chambered guns, you eliminate any potential problem by using solid based wadcutters.

[porkchop]

I'm starting to understand what your explaining Outpost, it's hard to find a wadcutter load for a 357 and you really don't see any hbwc loads period. Thanks for your help.

[40-82 hiker]

Here is my load for .357 mag. Colt Trooper Mk III:

H&G #50 solid wadcutter, 2.7 grains Bullseye, nearly pure lead with 2% tin, .38 special case, sized .359 for my gun

This is a very accurate load in my Mk III. I agree as to NO for the HBWC. It is not needed for obturation, as the soft lead handles that nicely.

[40-82 hiker]

Computer trouble. Double post.