doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Balance at hingepin question

Rocketman,

Does the MOI change with the relationship of the gun to horizontal, or, it's position to the pull of gravity? Too, how about some pictures of your machine to measure it?

Hairy

Ever lift a truely great gamegun and question it's balance - think the makers were intune with this much more than we.

Some interesting comments. Rocketman's approach is the one and only truly good engineering approach I've seen to quantifying the gun's characteristics. Lowell's comment gives praise to those great gunmakers of the past that emperically developed some really great handling guns. John Mann's comments acknowledge that men are all built differently and thus a given gun's characteristics will be percieved differently by different people.

Builder, I think what you were experiencing with that K80 was that the MOI was relatively low for the gun weight. That could be due to a short stock or short/light barrels or both. Two identical guns but for their LOP will have different MOI's and therefore different "feel"/"swing weight"/"livelyness" or whatever the favorite buzz word is.

One thing I've concluded for myself; I like different MOI/overall weight guns for different applications. What produces the best shooting is not necessarily what I want to carry up and down steep hills all day long.

Hairy Clipper et al:
Shooting Sportsman magazine, Sep/Oct 2001, starting page 72, "Measuring MOI' by Don Amos. This is a major article supported with good pictures, dealing with Rocketman's updated/upgraded/up-engineered MOI measuring tool. THE early "MOI" measuring tool and explanation is shown in Gough Thomas Gun Book...but Rocketman carries the idea and tool/device design far forward.
Shooting Sportsman magazine, Sep/Oct 2002, page 18, "Reproducing Gough Thomas's Device" by Thomas Hamernik. The title says it all....a one page article with a picture of the device.
Unstated in this thread,(so far), is that Rocketman has kept a record of the many guns he has "spun", which gives his words and comments just that much more value.
Hope this helps.

Ian,

I do not have those issues in the archives, but, will try to find them. They sound like great articles.

Hairy

LG - To answer your question directly, "Yes." The Brit makers worked out good patterns for most shooting purposes. However, they worked them out for their most usual clients. They built to weight and balance. MOI was unknown until Thomas showed the application. So, whatever was done by gunmakes before Thomas, was done on intuition. The kicker for me is that there is little physical commonality between me and your basic Brit now and much less 100 years ago. Since I buy used, not bespoke, I have to deal with guns made for smaller people. So, yes, I question the handling of all guns, Brit best included, that come within my grasp.

HC - MOI is the same number in the pitch (up and down) and yaw (side to side) axis. It would be different in the roll axis, but we don't have a movement of the gun that involves roll, so I don't measure it. I'm having trouble with posting a photo of my MOI machine; I'll post one as soon as I can figure out what is wrong. It is small and simple. The gun turns a timed 360 degrees from a standing start under constant torque. That allows a calibrated MOI to be determined from the time.

Rocketman,

I know what you mean about "physical commonality" my maternal grandmother whose family came from Scotland was about 4'10". There were chairs in her home that looked like something for a child. I, however, am 6'4" and weigh in at 345 pounds. I have rather large hands. So much so that I had to have the 'nose' of the comb moved back on my Thomas Turner & Son SXS in order to properly grip the wrist of the stock, get the safety off and get to the rear trigger. For a while I had a double barrel single shot. Cars do not fit well either, or basements of old houses, etc.

Hairy

How they fit your body type is a different story, but right off the high end used gun rack, the really good ones are most likely perfectly balanced no matter who they were made for. I have yet to heft a nice gamegun and think it very hoggish.

LG - my point is that there is no "perfectly balanced;" "balance" in this case seems to be used as a summation for handling characteristics. Most now agree that there is no such thing as "perfect stock dimensions." A given set of stock dimensions and handling finerprint can be a very close fit for a number of people, but not in a generalized way for the entire population of shooters. Many/most people find the light weight, center balance, and low swing effort of a typical game gun to be delightful. However, "delightful" is far from "perfect." Once a shooter has gathered enough information on his own preferences for handling, most will find the the delightful game gun fits a fairly narrow range of shooting activity. Sorry, but I do not believe that game gun handling is "the answer."

Gun folklore, tradition, beliefs, etc., all are deeply rooted. Some deeply rooted in partial accuracies, or accurate only under certain circumstances, or rooted in total inaccuracies.

For me and my varied shooting activities, I find I like guns that have varied physical characteristics.

My sporting clays shooting has me favoring a 32" long barreled, very forward weighted, 7lb, 20g o/u or a 32" long barreled, very forward weighted, 7 3/4lb, 12g o/u.

Skeet, which I do little of these days, finds me wanting a slightly "quicker swinging" gun than the sporting clays guns I have. What little trap I shoot is done with my long barreled sporting clays guns, since I'm not a proficient trap shooter anyways.

My walked up over a flushing dog quail hunting has driven me to favor a 6lb 26" barreled, 20g or .410 gun. If I had a pointing dog, I would consider a longer barreled, "slower" swinging gun for the prepared shot, but not necessarily heavier (gotta carry the thing across the same terrain, just the same).

So, I don't even imagine a Brit "game gun" would suit my clays shooting better than my cheapo production guns, but may be as good or better than some of my various guns at my quail hunting.

Pheasant hunting the flatlands is yet another story. A 6 - 6 1/2lb. featherlight "game gun" doesn't quite seem ideal to me. Too "whippy" IMO. Phez are slow to take flight and accelerate. Once up to cruise speeds, they need a steady lead and consistant follow thru. This means a gun that has some swing heft is o.k., even desirable. You do have to carry it, but usually not up and down hills/mtns like quail/chukar. So, a slightly heavier gun is manageable.

So, just in my little knothole of the world, I like vastly different characteristics in guns for my different hunting. A classic Brit "game gun" would/does/did have a place in my shooting, but not for everything.