alien319- I have hunted whitetail with my G20L for the last two years and here are my impressions.
First of all, PRACTICE IS PARAMOUNT. During preseason, one needs to practice from the field positions that he/she will be shooting from. This is, hands down, the most important thing to remember. PRACTICE PRACTICE PRACTICE.
Second, the choice of ammunition is also important for the ethical hunting with the 10mm. I would suggest something loaded VERY HOT, such as DoubleTap (my first choice), Buffalo Bore, Georgia Arms or Reeds, or a good handload. Keep in mind that if you are trying to decide on one of a few different loads, accuracy should be the deciding factor. I personally use the DT 200gr XTPs but I think a good, fast 200gr (or heavier) flat nose hardcast would be sufficient, too.
Thirdly, when I hunt with a pistol, at least this year, I used a tree stand with a shooting rest. My own personal rule for hunting whitetail is NOT to take a shot at a deer without a solid rest. That means no running shots and no standing, unaimed, unrested shots. Not only will the stand help give you better locations but it will keep you elevated above the scent line of deer giving you a higher success rate. Ground hunting (still hunting) can be really tricky if you have to stalk close to deer since being that close makes it inherently easier for deer to smell you. I'll be purchasing a new "climber" stand before next season to pack on my back for my extended whitetail hunting hikes into the backwoods (armed w/ pistol only). It just makes sense, at least for me.
As for the maximum range that a 10mm will WORK on deer... I would say that a 10mm w/ a 6" tube and hot loads could take deer at 100 yards with proper placement -- however -- you need to truly understand the difference in shooting 100 yards, breathing normally from a BENCHREST versus being freezing cold in tne field with a less than ideal rest and stance and a non-stationary target while out of breath!
They are completely different. I can shoot amazing groups at 50 and even 75 yards with my longslide from the BENCH at a range but wouldnt try those in the field. I would probably try and limit myself to 20-25 yards with a less than ideal rest and MAYBE 50-75 with a PERFECTLY SOLID rest (which is rare in itself). You need to think like a bowhunter. Get close to make your shots effective and ethical. Please.
Also consider that I've reworked my Glock trigger to weigh in at about 3 lbs and is extremely smooth. Keep in mind that if you're not concentrating on the KEYS to shooting, the stock Glock trigger will fail you as a hunting piece. My KEYS to shooting are:
FRONT SIGHT - SQUEEZE - FOLLOW THROUGH - OFFHAND 60/40 GRIP - SURPRISE BREAK
Remember: Aim small, hit small.
And there you have it. Now practice up and go get yourself some venison. :supergrin: