Haha I set up a Bear Mag TD 46#. I was hoping for arrows I had ready. Well no sir. I had to go outside the box to find my way. After finding the proper arrow flight I contacted Rick with a few findings. He ran the data through his wizard box. He can work it back from the pic.

Nice , never chronograph my Bear mag’s

Well you probably will get some of both, but the first thing they're all going to ask is are you drawing a true 28" and what is the gpp?

I started by testing 2 strings with an arrow I thought was in the zone. After choosing the string I shot the arrow at 30 yards. To my surprise the arrow kicked strong weak and miss a 24" target to the right. Over the course of a very windy day I came up with a bare shaft that flew neutral. Not something you would think would tune. After more of the same this morning I reduced the tip weight and got my first sign of stuff. Rummaging through arrows I found the next spine weaker that was an inch shorter. I removed fetching and got perfect arrow flight. I repeated over and over to my satisfaction. I then reported my findings to Rick. He put the numbers in. One thing that made the number work is that the string was equivalent to a 6 strands fast flight the other is I was shooting 0 center. I said that has to be fast. He said yes. I ran back out and checked. The pic matches. The other data is surprisingly different.

Great thread Title " Root "

I know that Cameron (Rooty) knows how to tune, so I have no doubt of his results.

To save myself a lot of typing, here are two screen grabs of the calculations.

First without a PFF (personal form factor) entry.

Second with a PFF (personal form factor) entry.

Rick

Like the man said - "Believe it or not", but if you don't you'd be wrong. :-)

Rick

No I can't draw 28" with a 27" arrows

A 28" 400 spine with 125 tip flew neutral with 100 just stiff. I will work on that. These will be over 9gpp at about 185 fps.

Interesting Cameron. Are you using original red, green tip limbs, or newer ones? A or B mag, 1's 2's or 3's limbs?

A mag new #1 limbs

Impressive,, have fun.

I believe it. Personally chronograph a SK at similar speeds.

All My Bears have been in the normal speed range. That’s why when ppl say they are slow I just scratch my head. Have always shot right there with any other similar bow I have tested.

With 7.8 gpp arrow and 6 strands string, that’s slow by target standards but good for Bear T/D. Very ease to believe.

24 strand actually the string acts like a 6 strand

New or old A Mag?

Rooty, your bow is at its peak of draw weight performance, the short limbs have a short working part, the arrow is lite. It has all the ingredients to see that speed at least one time on chrono. I doubt there were 5 201fps in a row - more like 198fps aberage - but I believe the photo.

Damn average

New riser. Draven I'll see what the average is

Weather windy and cold. I played more with 500 spine and they will not tune longer than 27". I am usually working during later deer season. I do get time for birds. Here's a 28" 400 spine flu flu.

2 shots same

197 sounds solid. With my CV2s - the closest to the conventional design - I am getting 207 averages using 7.8 gpp arrow on my barebow rig (25" riser and medium limbs) at 28" with 16 strand 625 string.

A guy on primitive archery (DC) tried to hit 200 fps with a 10 gpp arrow with some of his wood bows. He did it ,but not with any consistency. He did shoot in the high 190's though which is impressive for an all wood bow. To give you an idea of what a well built wood bow should shoot in fps. 100 plus bow draw weight 40 lbs. with a 10 gpp arrow. 100+40=140 fps. with a 10 gpp arrow. Some of his bows shot 55 fps plus faster than that. My best was 20 plus fps faster than the formula.

652 not 625

I am narrowing the arrow down in high winds. 27-1/2" 400 spine 9.3 gpp. I shot similar weight testing strings average 185 fps. 400 spine stands out as last year with similar limbs on another mag and the Fred E. Riser they used 600 spine.

I expect similar to this. The fps was much faster

“To give you an idea of what a well built wood bow should shoot in fps. 100 plus bow draw weight 40 lbs. with a 10 gpp arrow. 100+40=140 fps. with a 10 gpp arrow.”

Not buying it. If you want velocity to scale with draw weight, you need to keep arrow Mass constant.

A bow of a given design should shoot roughly X fps at Y GPP, though higher draw weights can get bogged down by the mass of the limb. There’s always a law of diminishing returns. So I’m told ;)

Prove me wrong if you want.

What I really want to know is what that string is made out of.

No idea how to prove anything. Flight shooting wood bow classes follow your same rules? My string material which I have used for 5 years is Bloodline sk99 24 strands.

Not you, Rooty ;)

Your lack of knowledge precedes on primitive wood bows CL. Over and out.

Wood bow meaning self or backed?

That should have read GPI. My bad.

Bear TD ended up with 27-3/4" (bop including insert shoulder. 9.3gpp. 189,190,190 etc. stay tuned for next bow

Next bow has Moac limbs 40#@27. First tuned arrow 600 28.5" 9.3 gpp. Has shot a bit faster. 400 and 340 spine results to follow.

Nice!

You stole my arrow, Rooty!!

I’m terrified to think about finding out how fast I can shoot them…. But I still want to know what the secret ingredient is….

Bt both backed ,and self bows. Badger, Mark St Louis Badger ,and Arvin, Dave Mead, and some others will build wood bows that will shock with the velocities they get many of which are just plain self bows.

Next spine 500 bs 31-1/2 average 208

Have you used run two chronographs to verify these speeds? I see some low numbers and some high numbers from posters, most are in the middle though…makes me not believe the machines…especially ones with a chunk missing..lol

BT my deck has a groove on edge of outer deck board - as I laid .220Swift on a pillow to shoot downhill at a coyote on the pond dam......it looked good through the scope.....bore at 3-4 inches lower than scope center....haha. chrony chunk missing reminds me.

Not the first one I've shot. That's the name of the post.

Do you believe this one? 43#@27 10gpp. It averages 167 fps

Me thinks chronographs and their results are very variable.

Yes your right. Dynamic vs static. George once said it's the difference between hitting the target and hitting the dirt in field archery. Speed is fun but not very high up on what really matters. I use a dynamic release to tune my bow and sometimes check the speed for a giggle.

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