Cartridge, Caliber .30 Blank, Model 1909--This cartridge is identified by having no bullet, a deep cannelure
in the neck of the case, and the crimp sealed by red lacquer.
Corbin Manufacturing bring high-performance bullet seating to the hobby reloader with their Hand Cannelure
Cartridge overall length (COL) is important for proper functioning in lever guns, and the cannelure
on the 110-grain FTX is positioned in exactly the right place to achieve the 2.550-inch COL for the .25-35.
Adjust the expander to bell these shortened cases, then seat and crimp normally in the cannelures
. Cases for 300-grain bullets were maintained at 2.571 inches.
This is why most bullets for really powerful rounds of .40 and above also feature crimping grooves or cannelures
. While the crimped bullets may not seat exactly the right distance from the lands for the finest accuracy, in rifles designed to really shoot Cape buffalo or Alaskan brown bear we don't much care whether groups are consistently sub-MOA.
"The GMX has two cannelures
to reduce bearing surface and give metal displaced by the lands a place to go," he says.
For example, when Hornady 165-grain FTX and 170-grain FN bullets are seated to their cannelures
in the .32 Winchester Special case, the FTX extends 0.135 inch deeper into its powder space.
In rounds like the .30-06, the Factory Crimp Die can crimp bullets that don't have cannelures
when you need the bullet to stay in place.
"All we lose is the scarlet plastic tip." Yes, the GMX looks just like an SST, though the shank has two cannelures
to reduce bearing surface and give displaced metal a place to go.
Lon Skutt, of Custom Engineering in Saginaw, Michigan, meticulously turned down the rim and cut new extractor cannelures
A hard polymer tip increases aerodynamics and assists in immediate expansion, and two cannelures
reduce friction and fouling.
Some bullets, like the Hornady 300-grain HP/XTP have two cannelures
, so you have some room to play with overall length.