Measuring to the lands - experiment
Baring in mind I'm a stingy git and don't want to purchase more kit from Hornady, I've been faffing about for a bit now trying to find out the cartridge length when it touches the lands.
The other day I drilled out a primer pocket and trimmed the neck to standard speck and I crimped the mouth slightly in the vice so that I could just push a bullet in with a little finger pressure. I placed the bullet ever so slightly in the case mouth and loaded and unloaded the round to see how far the lands had pushed the bullet into the case. I took a measurement each time with varying degrees of success. All in all I wasn't that confident with the trial.
Fast forward to yesterday and I'm walking through Homebase with the missus and I spot some 6mm diameter dowel in the home section. I bought a couple of pieces and sanded them down to just under 5mm diameter.
This evening I placed the bullets fully inside my modified case and popped them into the rifle chamber. I pushed the dowel through the primer pocket until it pushed the bullet into lands. Fortunately the case mouth was sized pretty well so I able to withdraw the round and measure the COAL without any alterations.
Varying the pressure placed on the dowel obviously gave slightly different results but not a million miles out. After a few attempts I managed to get some quite consistant results. Here's a picture after I measured and recorded some Hornady 55grn V-Max, 53grn V-Max, Sierra 52gn BTHP and Nosler 40gn:
Quite suprised by the 53gn V-Max, especially as the Hornady reloading manual that I have recommends a COAL of 2.240"
http://i863.photobucket.com/albums/a...psyoqvz3kl.jpg
.22LR CZ452; .22 Hornet CZ527
Tikka T3 Varmint .223; .204 Ruger CZ527 Varmint;
6.5 Creed Bergara B14 HMR