Chamber throats in LCR cylinder?

...then bullets fired from that chamber will be sort of rattling their way down the barrel.
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If it's smaller than the bore diameter that would be true. If it's just smaller than groove diameter, it won't be ideal for best accuracy, but it will still be engraved by the rifling and should shoot well enough unless it is smaller than the bore diameter as well.

But yeah, it's not ideal for the throat to be smaller than the bullet.
 
Aguila Blanca, thank you for making that point. It’s like having an engine with one of the cylinders misfiring. Also, I’d like to point out that all the XTP bullets measure exactly .311”. So that chamber has a throat diameter that’s somewhat less than .311” which is definitely less that the bore diameter.
 
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So that chamber has a throat diameter that’s somewhat less than .311” which is definitely less that the bore diameter.
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Bore diameter spec for the .327Mag is 0.303". It is extremely unlikely that any of the throats are less than bore diameter.

As for whether the small throat is less than groove diameter (spec 0.312") that would depend on the actual groove diameter of your revolver. Which, it should be obvious by now, may or may not be spec. If you want to know what the actual groove diameter is, you can slug the barrel to find out.
It’s like having an engine with one of the cylinders misfiring.
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It's not even close to that. It's entirely possible that the one tight throat will have no measurable effect on performance at all with the ammunition you're using.
 
JohnKSa, I’d like to thank you for your thoughtful input. It’s been helpful.

*** Lest this be misconstrued, it was NOT intended as sarcasm.
 
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After leaving the case and jumping the barrel-cylinder gap,
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The bullet doesn't "jump" the gap. It's actually well into the rifling before the base of the bullet gets clear of the throat. You can see this by dropping an unfired bullet into the barrel and swinging the cylinder toward the bullet. The point where the bullet stops is where it's starting to engage the rifling. There's a good portion of the bullet left sticking out that will remain in the chamber throat.

While it's not desirable for the throat the swage the bullet below groove diameter for a number of reasons, I like for the throats to be at or very close to nominal bullet diameter.
 
Very interesting observation, and not one I've ever heard anyone else make!
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I first made it in a gun shop years ago when I heard a guy behind the counter talking about bullets yawing as they jumped the gap and simply pointed out that the cylinder face is only about .006-.008 inch from the barrel face.

From his blank expression, I knew that he wasn't getting it...so, I grabbed a jacketed 158 grain .357 bullet from one of those loose zip-lock bags in the store and dropped it into the barrel of a revolver...then swung the cylinder to show how much bullet would remain in the throat. With that particular combination, the bullet is actually starting to engage the rifling before the base clears the case mouth.

Incidentally...for best accuracy with any bullet and less fouling with lead bullets...an unfired bullet dropped into a chamber should stick in the throat, and push through with light to moderate force, depending on whether it's jacketed or lead...lead bullets being typically .001 inch larger than nominal diameter.

So, "yawing" can't happen. The bullet is guided straight into the barrel from the instant it moves until it leaves the muzzle...first by the case, then the throat...and finally the taper in the forcing cone takes care of any slight cylinder to barrel misalignment long before the bullet base reaches the gap.

Sometimes the answer to a question has been staring us in the face the whole time. We only have to take the time to look.
 
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That is definitely a flaw, but I don't think I could shoot an LCR well enough to tell the odd chamber. The OP may be a better shot than me.

Back in the revolver era, a target shooter might select his best chamber and load it in single shot mode for the slow fire event. He would then select his worst chamber and leave it empty for the timed and rapid fire.
 
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