Dodgy gc2 numbers?

[turkish]

So i feel ive been making inroads the past couple of days with my driving. Hitting it straighter with positive AoA. Took pics of my GC2 results today which with pretty similar ball speed and launch to 2 months ago (but less spin) was giving me a fair bit more distance. Sent to my mate.

He instantly ridiculed the stats saying the machine must be boosted or dodgy as was getting 248 carry off of 95mph ss.... i said ah but gc2 doesnt know clubhead speed it calculates back from ball speed and my SS is actually nearer 101mph... he said ok then same physics apply for the 138mph ball speed and to check out andrew rice website for optimum numbers and he is right... optimum carry for 140mph ball speed is 225yards carry.... grrrrr!

So can anyone make sense of these numbers to massage my pride a bit?


anonymous image sites

 

[GeneralStore]

Personally think you have great launch angle and spin, so can see you getting good numbers for your swing speed. I am unsure whether the swing speed is accurate or not, but if it is, then I think that carry distance looks a bit high

Googled for reference and saw this if it helps http://www.swingmangolf.com/average-golf-swing-speed-chart-2/

Personally for me, my swing speed is 103mph and my carry is 245 yards, total is 269 yards, but I have some technique issues so dont get the max out of my swing speed.

 

[turkish]

I agree they look good :-D Too good lol from what I have read online- I don't see how I could have that carry with that ball speed- I'm wondering if the shop was trying to sell a driver in that bay prior to me arriving!!!

PS these were 5 shots in a row at the end of my session with no deletions so even if the Carry is a bit on the high side I'd be pretty happy with the other aspects. Need to try and trust the swing on course now.

 

[Region3]

Unless you absolutely need to know an accurate carry figure because you need to decide whether to aim at a bunker or not, I'd just be happy that I had good spin and launch numbers. The machine is only guessing at carry distance anyway, it will make zero difference to the carry you actually get on course if it's accurate or not.

My opinion - forget about the distance it says, and work on getting a better strike. There's a good 20yds extra there for you to grab.

 

[turkish]

Yeah strike is, and has been for some time been an issue but it's all connected isn't it- heely spinny strikes were the bad ones now I'm hitting more out the toe which is better but still not perfect.

 

[the_coach]

for sure strike location on the face then AoA & dynamic loft & LA - being presented at impact is the big key to driver performance

big crucial key to all of this & the ability to be able to improve in the first place is what is happening in set-up - grip orientation - ball position/tee height - posture angles - alignments - the loft of the driver being presented at set-up

set-up plays a huge part bigger than most folks give credit too in the ability to even be able to make improvement in club head delivery

simple fact - set-up out of whack with what is optimum for a driver & the shot results will always suffer & fall short of what could be achieved with the same swing mechanics with a good set-up - set-up & grip hold are key

numbers to look at to improve first & foremost are the ones relating to strike so SF or efficiency (depending on the LM type) face angle to path

then club head delivery numbers of AoA & dynamic loft at impact (path or swing direction is very much linked in to AoA - get the AoA in a good place & path will tend to improve - the relationship between AoA & dynamic loft that's key to spin loft so spin rate)

no real point in - in depth driver practice without knowing where (exactly) on the face the strike location is -if no HMT unit available then impact tape or spray needed - as above all strike is key

focus on carry or overall distance not real helpful to improvement

would show the read outs to whoever is operating the GC2 service as they should really take a look & recalibrate also maybes the flash unit needs replacing as some of them may have stopped working

plus are these range balls being used - old stock balls that starting to wear not goin to help any

say you put those average figures on the GC2 read out into Flightscope or trackman (calibrated at around sea-level -normal temps - normal medium ground conditions (not 'hard running')

then for a launch ball speed - 137.7mph / LA(vert) 14.9º / LA(hor) -2.3º / Spin rate (back) 2700 rpm (s) 235.3 rpm / Spin axis R 5º / Peak height 99' / Carry 229 yards Total 237 yards

these figs optimized for a center strike

looking at the original read out the strike location most likely to be toe-side & above the horizontal axis of the face more loft angle here so the higher LA's plus a tad less spin

so although that's a bunch better strike location than out of the heel - so it's for sure good to have moved strike to a tad better area of the face it's still the area to look to improve in to give more bang for the $

even though efficiency(SF) # is 1.45 you want to get that more to 1.47 + (although .2 doesn't seem a big # it's a more than perhaps it's seems given the relative value of the SF scale

 

[Region3]

even though efficiency(SF) # is 1.45 you want to get that more to 1.47 + (although .2 doesn't seem a big # it's a more than perhaps it's seems given the relative value of the SF scale

This was GC2 without HMT, so the 1.45 SF is just a 'best guess' to calculate a club speed.

The OP says club speed is around 100mph which puts SF ~1.38 ish.

 

[turkish]

This was GC2 without HMT, so the 1.45 SF is just a 'best guess' to calculate a club speed.

The OP says club speed is around 100mph which puts SF ~1.38 ish.

Yeah No HMT so as Region3 says it's best guess. I would say that is probably about right for SF at 1.38 and for sure strike is something I need to improve but my path and AoA (and so spin and dispersion) was so bad it will need to take a back seat while I continue to work on these. I think in turn it should improve as I continue to make improvements on the above.

PS I think I'd be delighted with a SF at a steady 1.45- aren't tour pro's averaging 1.47?

 

[the_coach]

This was GC2 without HMT, so the 1.45 SF is just a 'best guess' to calculate a club speed.

The OP says club speed is around 100mph which puts SF ~1.38 ish.

yep Gary aware it's just the GC2 unit given the club head #'s are N/A - comment about the efficiency/SF #'s was looking to future practice with a more reliable unit or different kind of LM type
SF #'s are always a calculation (not guess)

& just trying to point out although 1.45 to say 1.48 doesn't appear to be a large 'gap' the .03 difference is a bigger value in terms of overall performance results than it seems

Yeah No HMT so as Region3 says it's best guess. I would say that is probably about right for SF at 1.38 and for sure strike is something I need to improve but my path and AoA (and so spin and dispersion) was so bad it will need to take a back seat while I continue to work on these. I think in turn it should improve as I continue to make improvements on the above.

PS I think I'd be delighted with a SF at a steady 1.45- aren't tour pro's averaging 1.47?

elite players & Tour Pro's average SF # is 1.48 - top players are higher still - means they are not missing optimum center strike location by much if at all

not sure what the swing action here is like - but if the delivery of the club is such that the handle is high so shaft tending to the vertical at impact - then it's a ways impossible to have reliable contact from the center sweet spot with good dynamic loft & good AoA
improve the angle of shaft delivery so the club head (speaking to driver only) is toe up through strike & it's a ways easier to repeatable put the sweet spot (cog) of club face to the ball

say you could optimize/improve delivery for even that 95 mph swing speed # with a LA of 14.9 but with an AoA of +3º given a center strike so ball speed of 140 mph a spin rate of 2400 rpm that would give a carry distance of 236 yards with medium ground total dis. 245 - rock hard ground total dis. 261 yards