doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Hands on a real cutie

Well...OK. But I am a firm believer in the adjustability of the human body, which is why I don't let a gun's dimensions bother me. I allow myself a box of shells to get used to the gun - any target I miss after that, it's my fault, not the gun's.

I am curious, though....you are stranded on a desert island, and a beat up lifeboat floats up with Jennifer Aniston, Faith Hill, and Shelby Lynne on board. Their clothes are ripped to shreds, they are cold, and are starved - starved for sex.

Do you tell Ms. Lynne and Hill to get back on the boat and start rowing because their swing radius and bob weight is a little off your optimum setting? Or do you say, "Hell ladies, perpare for blastoff! They don't call call me Rocketman fer nothin'!".

Maybe for rabbits in the briar patch!
The 25s seem to have this anti-gravity thing going for them.
So, they've fallen out of favor.
We are shooting sporting birds, not life ending metors speeding through space.

Couple of questions:
Unmounted swing effort, what is the axis of rotation? Is it the balance point, or is the gun assumed to be held part way out from the body?

Mounted swing effort, what is the axis of rotation (the butt?)? When the gun is shouldered it seems to nearly enough rotate about the butt. The real axis may be somewhere in the shooter's body.

Balance point - self evident, except how to reference.

Half weight radius - is it measured from the balance point? Do you put your hands on the gun so that half the weight is between them?

Overall weight - self evident.

Do gun makers use the MOI quantities? Obviously, some practical understanding of weight distrubution with or without the numbers has been used by makers.

And what gauge (er, bore) would this cutie be? Sounds about right for a 28.

I have seen this idea discussed before, but haven't seen anyone try to quantify it so scientifically. I think the idea has merit.
I have two guns with almost the same dimensions and weight; they both fit me well, yet one handles like a lump of 4x2, the other positively dances between the hands because the weight is concentrated between the hands by light, skilfully struck barrels and stock boring.
I wonder whether being able to quantify this so accurately takes away some of the magic of picking up a gun and just "knowing" it's right though?
RG

I'd say you need a real life, outside your basement laboratory. After all your effort your database is unpublishable because every firearms researcher knows that summary results have to be accurate to the fifth decimal place, weight in ounces must be stated to the nearest 1/64th of an ounce, and linear measurements to the closest 1/128th of an inch. Your scale is obviously not electronic NIH laboratory research grade, and your yardstick must definitely be pre-May 5, 1937.

Dave - if it ain't your thing, then just move on.

I've enjoyed Don's SSM articles and had the pleasure to meet him and swing a few of my guns at the Southern SxS. Although working through what Don's numbers are telling me brings back painful memories of a college Dynamics course 20 year ago, it is intersting stuff - for some of us. If it ain't your cup of tea, fine, but bashing the guy and his work is out of line.

Ken

The Tom Hammernick shoestring and stopwatch (torsional pendulem principle) method that Rocketman referred to earlier first shows up in print (to my knowledge) in "Shotguns & Cartridges for Game and Clays" by Gough Thomas pages 161-164.
Gough Thomas Garwood, M.SC, C.ENG., F.I.C.E, F.I.E.E. He was a working "chartered civil engineer" (back cover bio) who had an interest in "things shotgun" and an ability to write. Glad I got the multiple copies (mine and gifts) of his books on eBay years ago as they have become very scarce and pricey.
On pages 161 - 164 GT discusses balance, Figure 82 shows the shoestring and stopwatch method, Moment of Inertia (MOI) and how to calculate it and in Tables 12 and 13 gives data on Best Guns and then Other Guns.
Rocketman's apparatus is a modernized tool to measure MOI and has value if you learn the comparative language. And as Rocketman clearly pointed his MOI figures are "data" just as LOP, DAC, & DAH are "data".
MOI is an academically interesting "nice to have" once you have the gun in hand and quantifies why one gun feels like a "bridge-timber" and another, a "wand". The only serious problem I see with this MOI data is that virtually NIL gun sellers have it for their guns on offer....and maybe the vendor thinks that's a good thing if he's trying to move a "bridge-timber".
My $0.02 FWIW.

It is people like Rocketman who help us to grow in our understanding of why guns "feel" like they do. I am most appreciative of this "scientific" approach to the balance and feel of guns. I held in my hands today two guns which were stocked almost identically. Both 12 gauge, both 30" barrels both by British makers a Scott sidelock from 1910 or so the other a William Evans Boxlock. In spite of the appeal of the sidelock I can tell you that it is the boxlock that I would choose over the two. Why? Both were well balanced as to centre of gravity, both weighed 6 lbs 12 ozs. Both were well stocked with DAC and DAH and Cast just about identical but the Evans was just that little bit better in "feel". Rocketman has opened a window to objective evaluation which although we choose not to jump through it is well worth the look. Maybe one day purveyors of fine arms will include MOI and other pertinent information which could assist us better in appraising a guns suitability for us from afar. Just my pennys worth.

Don's contributions here are always interesting, well researched, polite and respectful. His 'life' is scientific research, one subject is shotguns. Most of us enjoy reading and learning more on that particular topic. Don's work attempts to quantify the previously unquantified. Note that most pioneers in any field are subjected to ridicule... only after their contributions have proven worthy, do they receive acclaim.

Don reached the status of valued scientist here before most users of this system had even registered. Bash him at your own risk, you won't win many friends.

PS: I'd like to shoot a round of skeet with that gun... just to attempt to control the uncontrollable!