Get a Grip: How to Select a Handgun by “Size”

[RJ]

Did you know you can select a handgun in your Size? Here’s how.

First, measure your Hand Size, defined as the distance from the base of the palm of your dominant hand to the tip of your middle finger.



Next, we’ll define Gun Size as the distance around the grip, from the rear to the trigger, and back.



Selecting a Gun Size approximately 90% (93% is ideal) of your Hand Size will result in a reasonable expectation of a good fit, in the same manner you enter a clothing store, knowing your size, to select a shirt or pair of shoes.

Use either inches or millimeters – Try it and see if it works for you!



Link to Worksheet – Inches

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

Link to Worksheet - Millimeters

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


(This study was originally conducted in three parts, links below)

Part 1

https://pistol-forum.com/showthread....-Size-(Part-1)

Part 2

https://pistol-forum.com/showthread....-Size-(Part-2)

Part 3

https://pistol-forum.com/showthread....usion-(Part-3)

[RJ]

Study Analysis and Supporting Data

There is no industry wide, universally recognized sizing system for Hand to Gun fit, akin to clothing (S, M, L, etc.), to determine one’s pistol “Size”. In 2023, new handgun owners, in particular those with smaller stature, are entering the market in increasing numbers. Historically, handgun grips have been sized for males, and very commonly selected based on large capacity, for duty use.

Because of these two factors, today’s prospective pistol purchaser may end up buying a gun which is unlikely to meet their needs, due to inadequate trigger reach.

To attempt to gain more information about this issue, in July 2023 a two-part Case Study involving research into Hand and Gun size was conducted. Part 1 was to determine if Hand Size was generally correlated with Glove Size (it was, no surprise), and to gather Hand Size among the study population, capturing data on 26 individuals.

Hand Size Table - Sample


Glove Sizing Data was then obtained from five different glove manufacturers, each of which used the “palm to middle finger” definition of Hand Size. The data was averaged, resulting in the range of Hand Sizes, for each Glove Size, ranging from XS to 2XL.

In Part 2, the study surveyed Gun Size.

The Author found no industry standard in place for Gun size. Therefore, to have a consistent value, “size” was arbitrarily defined as Grip Circumference (GC): the shortest distance around the entirety of the grip/stocks, including the trigger, measured along an axis from the rear of the grip at the “web of hand” position, to the vertical mid-point of the trigger face, and back. The study then captured grip size data on 66 different handguns.

Gun Size Table - Sample


It was postulated that Grip Sizes for guns i.e. XS, S, M, M/L, L, XL and 2XL could be determined by numerically proportioning GC, in the same bands as Hand Lengths, linearly scaled. The values of each “Gun Size” were then calculated, providing a way to place Guns into sizes, numerically.

Hand to Grip Data


A subsequent analysis of grip circumferences to hand lengths was performed on the 7 respondents who also reported grip data on 26 different guns they owned.

Hand to Gun Size Table - Owners who reported Grip Size


A consistent ratio of Grip Circumference to Hand Size was noted. This value averaged 93%, indicating a correlation between grip circumference and hand size (the study assumed that, in general, owners would have chosen “well fitting” guns.) Interestingly, this value of 93% corresponded almost exactly with the predicted ratio of grip circumference to hand length, in the tabular values surveyed.

The above analysis was then synthesized into the Worksheets, in Post 1 of this thread.

[T Smith]

Nice work, RJ! Just checked the numbers on my (subjectively) best-fitting handgun and came up with 93.3%!

[RJ]

Nice work, RJ! Just checked the numbers on my (subjectively) best-fitting handgun and came up with 93.3%!

Appreciate the feedback. Yeah, 93% seems to come up.

It's interesting; I have a P365 Macro Grip module in bound today. I'm going to take my tape measure and put on whichever backstrap (S, M, L) ends up most closely matching 93% of my Hand Size, as a start.

I've never been able to do that, ever.

[RJ]

Errata

I misremembered the average ratio of grip size to hand size in the tabular value, the actual value was not "almost exactly" the same as the predicted 93%, it's actually 90.3%. So, picking a grip size somewhere in the 90% range probably would work well for most folks.

I may tweak the worksheets but don't plan to overhaul them much past this point; the current versions will always be uploaded to my Google drive in any event, and the links will stay the same.

At some point I'll upload my analysis spreadsheet but there needs to be some tidying up.

I had thought of maybe publishing this thread elsewhere, but now I think about it, I will just leave it on pistol-forum. p-f is my choice of getting good, gun-centric information, so perhaps it will draw others here. I mean, I'm no great shooter for sure but I can do math pretty well, and this was a heavily math-centric project. I just find this stuff interesting.

Now that the main point of the study is concluded (i.e. can hand size predict "good" gun size") I'll try and think about perhaps adding an additional measurement to somehow refine the metric. Some folks have made some interesting suggestions, and I'll probably go back and tag those in the part 2 thread with some thoughts.

Lastly I just wanted to take a moment and thank everyone who took the time out of their day to comment and provide data for the study. It literally would not have happened without your contribution, and I appreciate it very much.

Rich

[RJ]

Errata
...

I may tweak the worksheets but don't plan to overhaul them much past this point; the current versions will always be uploaded to my Google drive in any event, and the links will stay the same.

Rich

Both Inch and Millimeter worksheets are updated with the latest current numbers, and posted on my Google drive.

For the avoidance of doubt, direct links are:

Inch:

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

Millimeter:

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

What they look like:

[O4L]

According to the chart I have a XL hand and carry a Medium gun.

[1slow]

.88,
HK USP 45, LEM.
HAND 8.5”,
pistol 7.5

I am the small % of the population that the HK USP 45 is made to fit.

[RJ]

.88,
HK USP 45, LEM.
HAND 8.5”,
pistol 7.5

I am the small % of the population that the HK USP 45 is made to fit.

Thanks for the data point.

For anyone else, if you would like to participate in this analysis, I'll be happy to continue including data. 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.


Using me as an example:

My hand size is: 7.3".
A gun that fits me well is a 1911 Springfield Garrison .45 ACP with thin grips and short trigger, with a GC of 6.6". My "magic ratio" works out to be 90.4%.

It's interesting (to me anyway) this ratio of 90% is almost identical for all four guns I own. They all fit me pretty well, but they are no where close to being what you might think as the same "size" (a 1911, Ruger LCR, and two P365 platform guns).

[Borderland]

Works for me. Large hand size and 1911 just right. I get into trouble with some double stack nines. Beretta 92 is just out of reach for me.