Bow draw weights and skill

[JazzJedi]

So I'm doing a historical campaign set during the 100 years war, and I wanted to come up with rules for draw weights and bows. Do these rules exist anywhere? I have a little archery experience: I own a 45-lb. super-grizzly recurve, and a 70-lb. Optimus compound bow - I've gone bow hunting about a dozen times in the last 20 years, but I don't shoot as regularly as I should - maybe 2-3 times per month for a couple of hours each time. I've tried firing a 100-lb warbow, and it is difficult, but I can shoot it 5-6 times before I need a good rest. I imagine I could pull a 130-pound bow maybe once before needing to rest for a good minute.

Anyway, what I've learned from my experience and my friends is that there is a draw weight that I can fire basically all the time without too much fatigue, and a draw weight above which I will tire pretty quickly. So decided that this "normal draw weight" is equal to the ST of the firer, and the draw weight equivalent is BLx3. This uses the rules as written. So a ST 10 bow has an equivalent draw weight of 60-lbs. ST 9 is 48 lbs. ST 7 is a 30-lb. bow. ST 12 is 86.4 lbs. ST 15 is 135 lbs, and this is equivalent to the estimated strength of the Mary Rose warbows. Maybe ST 16 for the most powerful of those.

Your "maximum draw weight" is equal to your ST+2. But firing a bow over your ST requires an Ready maneuver to draw the bow (it requires a different posture and a LOT of effort) and you can't benefit from more than one turn of aiming, and it costs 1 FP per second to try and hold it in the Ready position!

As for skill, I can hit a bullseye at 40 yards pretty often (90%+) and have shot White-tailed deer at that range in the heart with both my bows. So to hit a deer in the vitals at 40 yards has the following modifiers: Range (-8), Heart/Vitals (-3), Accuracy 3, Extra two turns to aim +2, All-Out Attack (Determined) +1. So assuming that my effective skill is 14 (90% accuracy), that would mean I need a base skill of 16? That seems too high to me, but I'm probably missing some modifiers. Now I know people will say that my target accuracy is not the same as combat accuracy, but I respectfully disagree. Hunting is stressful, and I've shot many deer (longest was 60 yards) and never missed a lethal shot (I've shot six deer total). I'm not exceptional or prolific as far as bow hunters go, and my 84-year old father went bow hunting last year and shot and killed a deer at 60 yards with his 55-lb recurve. He's been bow hunting for years, but never practices archery since he was a kid! He is a bit of a freak... Any better insights of converting real world accuracy to GURPS skill would be appreciated.

The reason I mention this is that English longbowmen were required by law to practice archery from the age of 15+, but most started earlier (age 10+), and they practiced regularly. They had an archery culture and used heavier bows all the time, although probably not for hunting. Either way, I only imagine that their skill must be a LOT better than mine, and Mongol archers were said to be able to hit a man from a galloping horse at 100 yards more than half the time! That has to be an average skill of 20 or higher! Does this mean the "average" Mongol have Bow at DX+8? Well, it wouldn't surprise me, but that seems a bit off based on the official "expert" skill level being 14. I don't consider myself an expert at all, and I shoot pretty average for our group.

My apologies for the long post, but archery is an important part of the campaign and since all the players are archers, we tend to talk in terms of draw weight, draw length, arrow weight, etc. This was our attempt to convert our knowledge to GURPS rules. If these rules have been covered elsewhere, please direct me, and please offer some criticism and feedback. Thanks!