Char-Gar
07-23-2005, 09:58 PM
I enjoy the 30-30 round very much and my current playtoy is a 1960 Marlin Texan carbine. With a good 170-180 GC bullet over 17/4759 it will give 2.5 MOA accuracy, plus or minus a tad depending on the bullet.
This Marlin has a land diameter of .305...Pretty large even for a Marlin. Yesterday I was shooting the above load over two 170 grain CG bullets and the results were just the same in terms of accuracy.
The first was a custom Mountain Mold with a nose that casts at .307.
The second is SAECO 305 with a nose of .303. Both bullets were sized .311 which is as large as the Marlin throat will accomidate.
One mold .002 over land and the other .002 under land. Both of these bullets are of the traditional 30-30 design with about a 58% body and a 42% nose.
I am left with one of two conslusions.
2) The smaller nose is slugging up to fill the bore
3) .002 nose undersize on a bullet that is 58% body does not affect accuracy.
I know accuracy would suffer with a .002 undersize nose on one of those long nose bore riders, but it doesn't seem to matter much on these "mostly body" bullets.
Any comments, corrections or experiences to share on the subject at hand?
This Marlin has a land diameter of .305...Pretty large even for a Marlin. Yesterday I was shooting the above load over two 170 grain CG bullets and the results were just the same in terms of accuracy.
The first was a custom Mountain Mold with a nose that casts at .307.
The second is SAECO 305 with a nose of .303. Both bullets were sized .311 which is as large as the Marlin throat will accomidate.
One mold .002 over land and the other .002 under land. Both of these bullets are of the traditional 30-30 design with about a 58% body and a 42% nose.
I am left with one of two conslusions.
2) The smaller nose is slugging up to fill the bore
3) .002 nose undersize on a bullet that is 58% body does not affect accuracy.
I know accuracy would suffer with a .002 undersize nose on one of those long nose bore riders, but it doesn't seem to matter much on these "mostly body" bullets.
Any comments, corrections or experiences to share on the subject at hand?