Hand Length to Gun Fit: A Case Study: Analysis and Conclusion (Part 3)

[RJ]

Simpler still.


Hand_Size_Design_Notes.pdf

[RJ]

Knife and forked a potential hand out, rewickered the text into panels, reusing the general theme of my QRCs. Ish. "Catchy Title" ended up being "Get a Grip"...eh I dunno. I probably should not quit my day job.

Goal is to make this concise and self-evident, I would really like to just use symbols so it could be language-free but can't figure out a way to do that without English.

PS the screen grab is poor, grab the PDF if you want, it's much more legible.



Get_a_Grip.pdf

[RJ]

Some more graphic tweaks. Moar monochromatic for B&W printers. Less busy. Use of outlines for hand and gun. More orderly fenestration of the panels, a la house windows. Fewer and less wordy panels. Consistent line color and shadow on panels. Change to light silver for main 1" grid background, and make larger overall. Rotate "Arrow" in middle pointing down to table. Add boxes for user to record their hand and gun size.


Get_a_Grip_1.3.pdf

[Leroy]

I think you will need to add grip size (circumference starting under trigger guard up and around the beavertail) and trigger release point as well. The trigger reach only tells 1/3 of what you need to know but the chart is well done and looks good. Nice job.

[RJ]

I think you will need to add grip size (circumference starting under trigger guard up and around the beavertail) and trigger release point as well. The trigger reach only tells 1/3 of what you need to know but the chart is well done and looks good. Nice job.

Thanks. I've pondered adding nuances like that, but with all the different possibilities of trigger (DA, SA, LEM, DAK, and so forth), have so far resisted the urge. I started with a ill-defined goal of trying to do a better job of helping newer shooters pick out a gun, in particular those with smaller hands, entering the market these days. I think as a first order solution, making sure you have AT LEAST enough reach to get around the trigger, is a reasonable goal.

And if I were selling guns, I'd want something I could hand someone and have them "get it" in like 10 seconds or less. More than that, I think you'd lose them.

But yeah I'll keep tinkering with this idea of more/better data, just now sure how to do that, at the moment. Appreciate the input.

[RJ]

Did a few more final tweaks, my engineering OCD about aligning things in boxes got the better of me.

I'm more or less happy with the "Get a Grip" concept at the moment, so to save some admin burden I am going to upload them to my Google Drive. I've created both a Metric (in mm) and SAE (in inches, duh) versions, so you sausage-eating, beer-by-the-liter Austrians can actually use the data, and not have to squint over ze slide rule.

Link to SAE Version:

https://drive.google.com/file/d/17cY...usp=drive_link

Link to Metric Version

https://drive.google.com/file/d/11Hn...usp=drive_link

Any future updates will get made to the ones on the Google drive. I've grabbed a screen shot of the metric one to show you what they look like now, but the pdf is much, much better:

[Chemsoldier]

Possible implications:
-If this is accurate, a lot of people are running guns that are bigger than their hand is optimally suited for. Asking everyone to run a handgun optimally sized is not realistic for many, especially those on the smaller end of the hand size distribution. Especially those who carry guns professionally, and competition shooters. Additionally, it is observed that smaller guns are hard to shoot well. Claude Werner and others observe that the J-Frame is a gun for those that are into putting in the effort and time to master it. What do you do as a XS hand sized person, who wants to defend themselves, who is also simply not interested in being a samurai of the pocket pistol?
-Jim Cirillo claimed in his videos that he had small hands (more accurately, that he had short fingers) for his size. Cirillo said he had to use a c shaped grip, with the meat of his hand slid around the dominate side of the grip rather than putting the meat behind the center of recoil. However, Cirillo was a body builder in his youth and even into his old age had big beefy weightlifter's hands. Some of sub-optimal gripping's penalties may have been mitigated by his hand strength.

Perhaps, while grip strength is beneficial to all pistol shooters, there is more benefit per unit of grip strength increase, for those shooting pistols sized above their hand's optimum?

[RJ]

The first "output" thread was posted a few days ago:

https://pistol-forum.com/showthread....-by-%93Size%94

This is a snapshot in time for the analysis, but I'm still noodling on the numbers, as I'm cleaning up the analysis spreadsheet.

I've gone back and forth on including the outliers both large and small on reported hand sizes. I eventually decided to just include them all. I also found a bunch more glove / hand sizing data sources, so threw them in the hopper. I did some graphic work, to create a summary picture of the data. For Hand and Grip, the tables look like this:



Looks like a lot of folks with "size M" hands. I dunno if that is representative of the US NA Male population at large or not. I've seen some sources indicate "Average" hand size is around 7.6", but I've never seen a source on that.

As well, a very large percentage of the guns reported are in the M/L category. Not sure what to make of that, either.

Obviously all this affects the bands in the worksheet handouts, and I don't plan to update those at the moment, but this is interesting to ponder.

[RJ]

Lately I've been attempting to clean up the analysis spreadsheet with a notion to post it on the Google drive. That's led me to a couple things.

First the one-page handouts will be revise; the data is changing slightly, as well as quite a bit of formatting updates to make them even simpler and easier to read.

Second I've switched to using the average glove size (I'm up to 8 sources for Glove data, all of which use different values, amusingly enough). I did keep a comparison with the Study Population (up to 26 hand sizes) and there is good alignment at both the XS and 2XL ends of both tables. So I tend to think p-f is representative of the average glove sizes, which is useful to know, despite us having some folks with very large hands.

I may also change my mind and circulate the output of this study elsewhere, I think it will be interesting to spring this on Gen Pop in other forums and see what happens. I think the concept of actually measuring hand sizes to fit to a gun (with a specific number in mind) isn't something that's very commonly thought about.

Planning to do this in the next few days. As a teaser, the new "handout" image at version 2.0 (I'll post the pdf soon) looks like this:

[RJ]

Thought I'd output a couple revised charts, and take a more detailed look at this "90%" figure of grip to hand that keeps coming up.


I decided 7 sizes was too busy, so I just added XS and S for "Small", left Medium, and put M/L+L and XL+2XL together. Now I have four values, for both hand and grip. Study is up to 31 hand sizes and 72 different pistols. Outliers didn't change, but I did peg the Max and Min of each for the worksheet/handouts, so the numbers there would not change.

Chart for Hand Sizes:


Chart for Grip Sizes:



Secondly, regarding the study conclusion that 90% grip to hand ratio is a good starting point for fit, I now have 10 folks who reported both Hand Size and Grip Size for at least one pistol. I'd still say this is a good rule of thumb, inasmuch as the data seems consistently around this figure:



The substudy folks average 92% with a std dev of 6%. But one person appears to favor a larger grip than most, so if I remove that, as an outlier, the average is 90%, with a std dev of 3%.

I'd really like to get more information on this ratio of Grip Circumference to Hand Length. If you would like to help, I just need:

1) Your hand size and
2) For a gun that fits you well, what it is, and it's Grip Circumference.

I can work with inches or millimeters. I will then add this data to the study database. All responses will be logged anonymously, I don't retain any association of data to a person, at all.