Bullet size and groups

[10x]

I inadvertently sized some Lee 150 FPGC to 0.309" and attempted to get groups with my 100 year old Savage 30-30 using H335 powder.
Velocity was 1750 fps . Groups were terrible - over 6" at 25 yards with some bullets hitting the paper sideways.
Another batch of the same bullet sized to 0.311" with the same load of H335. Group size dropped to under an inch. Not bad with open sights and a starting load.

[Tatume]

Sounds like your gun doesn't like 0.309" bullets. My Marlin 336 does, and shoots them very well. "The proof is in the pudding," as they say.

[Ed_Shot]

I have .309 .310 and .311 sizing dies for my 450. I'm a firm believer that you have to let the weapon tell you what it likes. That's one of the main reasons I reload.

[plainsman456]

Yep,after doing some reading and a few shooting sessions i have found out,it don't hurt to have options when it comes to sizing cast.