New SBD bowstring and Arrow Question

[JDow3]

Hey folks,

Noob here to trad archery and have already learned a bunch from the members on this site so thank you all.

I just picked up a new sbd bowstring from Pierre for my 64" Montana LB. I chose the ultra 6. I took it out this afternoon and did some backyard shooting and love, absolutely love the new string. The arrow penetration into my rinehart was noticeably deeper.

Now, I'm shooting a 50# bow with a 26" draw length. I'm shooting easton traditional only carbon arrows spined at 500 with 125 gr points. No inserts or anything. Pierre had mentioned that the recommendation for the sbd bowstring is 10gpi for the arrow for the ultra 6. My arrows are 30" and come in closer to 9gpi.

I shot the 500 spine arrows today and my accuracy was pretty much on par with how I normally shoot, still need some work. I do have some easton's spined at 340 for my compound bow. I decided to run them through my lomgbow with 125 gr points. The arrow flight was crazy on the 340s. I was all over the place and the arrows were sticking in the target kinda slanted.

So, my two fold question - The 340s seemed to stiff. Given the 500s shot well, should I change up and maybe try a 400 or just stick with what I've got.

Part 2 - If I stick with the 500, should I add some weight up front?  Maybe heavier grain points?  How does more weight up front effect the flight of the arrow?  

I do plan on hunting next fall with my longbow and have read members here talking about adding weight. I never did that with my compound and it never mattered. Is more weight up front something I need to consider with trad gear?

Sorry for the long post and questions. Any assistance is greatly appreciated.

Thanks!

JD

[yth-mnstr]

JD,
If you have heavier points, give them a try with the 340's.  Then' if you don't get good flight, bump down to the 400's and give them a whirl.

[Chesapeake]

If your 340's have vanes that won't help flight. The vanes can bounce off the riser.

[Piratkey]

50# at 26" draw lenght.....if you cut you arrows at 28" ,you can go to at least 250gr up front.

[Piratkey]

For the 500 spine.

[Stump73]

I agree with piratkey

[katman]

Replace point with a weight that gets you to 10gpp then bareshaft tune by cutting until you get a great tune, link to tuning using bare shaft planning method.   http://www.acsbows.com/bowtuning.html

[mahantango]

Is the bow marked #50, or are you drawing #50 at your 26" length? If it is marked #50@28", you are barely getting #45 out of it,and with the Montana being cut before-center I would even drop to .600spine.

[M60gunner]

.340 is way over spined for 45# of pull. Like above what Katman says.

[olddogrib]

what mahantango said. If it's 50# @ 28" your only pulling about 44# @ 26". If your arrows are flying well, you're fine.  If you're actually pulling 50# try Piratkey's advice.  SBD Ultra's are great strings!

[JDow3]

Thanks for all the feedback y'all.

To clarify, it's 50# @ 28" so I'm drawing around 44#s

The 340s do have vanes on them. I'm fully committing to trad so I'm going to sell my compound and I believe I'll sell these arrows with it.

Katman - Thanks for the link to bareshaft tuning. I'll check that out when I get back from church.

Piratkey - Sorry for a noob and probably obvious question, but what will shortening the length and adding more weight do for the arrow flight?  I definitely want to practice with what I'm going to hunt with and if it's better to have more weight I want to do that.

[drewsbow]

stay with the 500 for sure

[JDow3]

So I just had a quick target session after picking up some 175 gr points. There is a discernible difference in the grouping. I did a 3 shot side by side comparison on two different targets with same distance of 10 yards. In 5 tries, the 175gr won 4 times.

I still seem to be pushing a little left but that's probably me still finding my form consistently.

Also, the penetration between the 175 and 125 gr are not even close.

[Bladepeek]

You may be close with the 175s on the 500 spined arrows, but I would bet you may be still on the stiff side. From the way you describe your results, I'd definitely try heavier points. Points are dirt cheap and easily changed. If you start getting good flight with 200 gr or heavier points and want to go somewhat lighter, you will have to shoot full length (32") or drop to a weaker spined arrow.

If you are getting anywhere near decent flight out of the arrow, I'd work on getting smaller groups before getting too carried away with fine tuning.