.327 FedMag accuracy problems

[TfflHndn]

I have a Smith 632 in .327 Federal Magnum. It's pretty accurate with .32 H&R and .32 Long ammo, but the group opens up a lot with .327 ammo. Not sure why. I've used factory semi-jacketed, lead and hi-tek coated lead, and they all lose accuracy when loaded for 327. Is the bullet just being pushed too fast and skidding, so it doesn't have the spin to stabilize? No leading/fouling problems, so I don't know what the issue is. Any thoughts among the wise ones out there?

 

[Saleen322]

My 327 is a Blackhawk so my frame of reference is with a 5.5" barrel. The 100 grain jacketed SP factory round (Federal) groups just under 3" @ 25 yards for me. I do cast some bullets but all of mine are gas check bullets. The lead gas checks group the best from my gun doing 2" and sometimes less @ 25 yards. I have not tried any non gas check bullets as I thought the velocity was too high from my revolver. Hope this helps.

 

[Kosh75287]

Can you mic the diameter of your forcing cone and the cylinder holes where they align with it, then compare that with the diameters of the projectiles in the .32 long, .32 H&R, and .327 Federal? I'm betting that, if the first two deliver better accuracy, their bullet diameters will be closer to that of the cylinder ends and forcing cone. Perhaps the difference(s) will be only one or two thousandths of an inch, but I'd bet it's enough to explain the difference in accuracy.

 

[herrwalther]

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