I own an Anchutz .22 Hornet with a 600mm barrel with a .224 inch bore,
but I'm not much impressed with its performance using the 40gn Sierra
and 11gn of W-296. My gunsmith has recommended that I can gain about
150fps if I have the rifle rechambered to K-Hornet. Do you think this
would be worthwhile? How much velocity do you think I would gain? Can
you recommend some loading data?
A good Hornet's effective range is about 150 metres on varmints. The "K" chamber
extends the range about 50 metres. I'll take the fireformed version over the standard
Hornet any day. You retain the accuracy, get a more power and loading is a lot less
critical. With a factory load the 45gn bullet starts at 2650fps. Mid-range trajectory is
.8" at 100yds., 4" at 200, 12.6 at 300. Muzzle energy is 700 ft/lbs at 100yds., 430,
at 200 345 and at 300 only 238 ft/lbs. At 200yds. a crosswind drifts the bullet 7"
compared with 3-1/2" for the .222 Rem. This is why 200yds. is a bit far to pinpoint
hits, and bullet blow-up is inadequate. At that range they penetrate but don't expand
and killing power is poor. These factors favour conversion to K-Hornet. Hornady
makes a 35gn bullet and lists a maximum load of 13.2gn of W-296 or 14gn of Lil Gun
for 3200fps. The manual also lists 13.5gn of Lil Gun behind the 40gn V-Max for
3100fps, while 11.5gn drives the 45 grainer at a handy 2800fps. Loading the K-Hornet
is non-critical but always work up loads in one brand of case as they vary greatly in
capacity. Hornet brass is very thin and one has to exercise care when seating bullets
to avoid crumpling case necks. I've not had this happen with the K- version. I'd
definitely recommend rechambering your rifle.