Okay, I have a post going about arrows, but have more questions. I have a Bear Montana 50# at 28". I put a cloths pin on the shaft and pulled the bow back to my anchor and measured from the pin to the valley 27.25" The 1916 arrows I have show a weak spine at 20 feet when shot into a bag target. I have 2" of wiggle room for tuning. If I go the entire 2", could I go with a heavier tip weight? How heavy? I put a fletched arrow with a 125gr tip on the scale and came up with 470 gr total, is that enough to deer hunt with? I am thinking about using Magnus 2 blade heads with this set up. Do I need a heavier arrow?
You didn't say what point weight you shot with?470 isn't bad.If you could cut 2" off the shafts,you could probably add 30-50 grs of point weight but only tuning will tell.
If it were me, I would cut the arrow to 28.25 and bareshaft tune. You will have to add more weight up front to make it tune, but thats a good thing if your deer hunting. May be as much as 200 or more grains, you won't know till you bareshaft tune. Just buy the Magnus glue ons and epoxy the correct weight screw in adapter in them when your done tuning and your good to go. As far as arrow weight, your already there. Your probably pulling 46-48 pounds now, already at 10 grains per pound with your long arrow. Your gpp will only go up with the shorter arrow and heavier point. This would be an excellent deer hunting setup with plenty of penetration potential, IMHO.
I have been shooting with 125 heads.
QuoteOriginally posted by Reaper TN:
If it were me, I would cut the arrow to 28.25 and bareshaft tune. You will have to add more weight up front to make it tune, but thats a good thing if your deer hunting. May be as much as 200 or more grains, you won't know till you bareshaft tune. Just buy the Magnus glue ons and epoxy the correct weight screw in adapter in them when your done tuning and your good to go. As far as arrow weight, your already there. Your probably pulling 46-48 pounds now, already at 10 grains per pound with your long arrow. Your gpp will only go up with the shorter arrow and heavier point. This would be an excellent deer hunting setup with plenty of penetration potential, IMHO.
Good advice there. Your draw is most likely shorter than 27.25" under actual shooting conditions. The clothes pin trick will give you an idea, but most of us will draw shorter than that when actually shooting. You are in good shape weight wise already. If you are happy with the broadhead you are shooting, you can simply cut about 1/4" at a time until you have your arrows flying perfectly. If you want to add weight, go ahead and do so and continue to trim for good flight. Once the arrows are cut, putting more length back on is tough.
If you get them too short, you may have to add more weight than you'd like to get them tuned. If you plan to limit your shots to 20 yards and under, extremely heavy arrows won't be a problem. Just remember, if you get too carried away with weight, the arrows will drop rapidly much beyond that distance. I find that once I get above 12 grains per pound of draw weight, I really notice a difference in arrow flight. From 9 gpp to 12 gpp, there is negligible difference in trajectory, but it seems to drop off quickly after that. Your mileage may vary.
You may end up with 28.25", but I'd kind of sneak up on it if it were me. I shot 1916s with 150 grain Woodsman heads out of a 51# bow I had and got good penetration with it. I think the shafts were around 29" if I remember correctly. My draw is about the same as yours, so I was probably shooting closer to 47-48#.
Matthew I love my Montana 50@28. The bow has a center cut of 0. Wish I could tell you I have the perfect arrow set up for you but I draw a true 30" and my setups would not work.
The information below is what I have used over the last 4 years to tune all my bows.
If you have not done so I would suggest you go here and download the printable version.
http://www.acsbows.com/bowtuning.html
The other tool you might want to use is Stu Millers Dynamic Spine calculator. You can find that at http://www.heilakka.com/stumiller/ many of us have found this a great tool and will get you in the ballpark real fast.
Before using the calculator. Please download and read the instructions.
Here is a profile of your bow through the calculator
(http://i261.photobucket.com/albums/ii45/heilakka/matt.jpg)
Using the 1916 you do not have all that much wiggle room. Notice I gave you a bop of 29. I also used a side plate of 0.125". Your set up is fine for deer. If you want a heavier arrow you could go with 1918, bop of 29 add a 50g adapter.
this would give you 540 total.
Good luck and have fun
Well I cut an arrow down to 29.125" from the valley of the nock. With a 125 grain head, the arrow is straight when shot with a cant and just a touch weak with a straight bow. I could cut more, but I would like to use a 125 gr head, so I am going to leave it be and shoot more over the next few days and record what happens. I can say this, by cutting to where I am at, my arrow goes into the bag target deeper now. This will give me a 453 grain arrow when fletched with 3 5" feathers. So ballpark 9.68 grains per inch at 47#.
just got my son a 45# Montana and am wondering what brace you guys set your's at?
7.75" is where mine is at for brace.
Bear recommends 7 1/2-8 1/2. I shoot mine at 7 1/2.