Ok here's another tuning question....... I am shooting a straight limb longbow 68" ntn ,cut to center , 55lbs @ 28" and drawing 28" w/b-50 string. I wanted some arrows that I could shoot with 160gr heads. Cut to 29" BOP 45-50 poc's are showing stiff bareshaft even with 315 up front. I was thinking form related so focused on my form still same results. Does anyone shooting similar bows see the need to drop down to 40-45 spine shafts ? This bow is similar to a hill style bow except it is cut to center. I am using Velcro as a strike plate.

I would bet they're weak. I shoot basically the exact same setup, string and all. I draw 29". 65-70 surewoods fly perfect with Magnus 1's.

They should be weak with 315gr up front. I considered the typical 10lb spine reduction due to the limb design and opted for the 45-50's. I will give it a go again tomorrow and see what the deal is. I would lean toward form related issues but everything feels good with my back tension ,anchor and release.

Those shafts shouldn't be too stiff for your bow, unless perhaps it's a self bow.  How do you get 315 grains up front?  Are you using woody weights? Are you sure your bow is cut to center and not proud of center?  Even if cut to center, a thick piece of velcro for a strike plate will move the arrow out quite far, having the effect of stiffening the dynamic spine.

Are you hearing any noise like the arrow bouncing off the bow?  That could be an indication of an overly soft spine, and/or brace height that's too low, which would send the arrow to the left. Of course, a too stiff spine can also bounce off the side plate and go to the left, for a right-handed shooter. Plucking can also send the arrow in that direction.

Could be lots of things.  You'll just have to keep working at it to try to sort it out.  Good luck.

I am sure about the center cut. I am using 125gr woody weight and 190gr field point. I will start over in the morning , it very well may be kicking off the shelf. I really thought the 160's would put them on the money......Better to have this problem now than a week before season opens...........lol

Wow!  What kind of bow are you shooting there? Even with a B 50 string slowing things down you should be folding those arrows in half at 55#   I shoot 65/70's out of my 55# long bow with 185 up front, but i'm drawing 30".... something ain't right there..

two questions...first and foremost how tight are your nocks and next is how low of a bh are you using?  bh wont effect it to the extent a tight (or loose) nock will.

Tight nocks will show stiff hanging on the string longer than say a BC or an older mecury speed nock or hill style nock.

Are you right handed? (not trying to insult your intelligence, I cant pick my nose lefty LOL)!!!

Usually if its bouncing off the site window you'll hear/see it unless its very subtle imho.

Here are pics of the bow......   http://i1383.photobucket.com/albums/ah320/coastaldesign1/102_1447_zps91496b17.jpg     http://i1383.photobucket.com/albums/ah320/coastaldesign1/102_1452_zpsb384640b.jpg      http://i1383.photobucket.com/albums/ah320/coastaldesign1/102_1449_zpsd39e0d96.jpg

Ok ,started over this morning..... 45-50's w/ 160's up front are bareshaft dead center out to 20yds. The fix was ....Nock point too high (kicking on release)and also made an adjustment to the strike plate (moved slightly forward). Also added two twist to raise the brace height a bit. Looks good now moving on to fletched shafts for some broadhead tuning !!!!

I shoot 60/65 cedars 29 BOP from my 50 lb selfbow and it's 7/16 or little more from center I bet you are WAY weak. I would guess 60/65 or even 65/70.