Correct Bullet Sizing for 45-75

[sass2924]

The Cimarron site says that the groove dia. for their 45-75 (as well as all the 45 cal rifles) is .456.  I was planning on sizing my bullets to .457, .001 over the groove dia.  Does anyone else do this or see a problem?  Iv'e seen a couple people sizing to .458, is there any benefit to this?

[Harve Curry]

I think the standard rule has become .002" over groove diameter for cast bullets to shoot at their optimum. This is as long as the chamber willl accept them.

[Hell-Er High Water]

For what it's worth, I cast and size bullets for my shooting pardner's Uberti 45-60 to 0.459" and he gets excellent accuracy with them.  I also size to this same diameter for my Chaparral 45-75 and various 45-70's that I shoot.  The bullets are cast out of Lyman #2 alloy for smokeless loads and 20:1 alloy for BP loads.

I tried 0.457" & 0.458" but the 0.459" works the best in all three of these calibers for us.

HHW

[Hobie]

I size to .458".  .001" to .002" over groove diameter is standard. 

[Leverluver]

My 45-60 slugged .4573".  I seriously doubt that they are making the 45-60 and 45-75 out of different barrel sizes.  Ditto on the .459 as it seeemed to work the best for me.