This is a question for the guys in the know here as far as doubles are concerned. What are the forces that cause a double to "come off the face?"

Does extensive shooting contribute to this? Obviously high preassure loads would cause this but, lets say a rifle that has been subjected to only factory ammo. There is a thread on another forum about how to tell if a double is off the face but there is not much info on what causes it. Also the info on the thread is pretty contradictory as to what one person uses as a indicator of a rifle being off the face and what another uses.

I have a best quality sidelock double with no issues but at all the shows I pick up various doubles and feel them, open the action and close it and some feel loose like they close with no effort, some are tight...etc. Some of these rifles are very old and I assume have only been shot with factory ammo so what is the oppinion of the guys here? Can extensive shooting loosen a fine double to the point that it needs to have the hinge pin replaced? If so what is "extensive" shooting for a double.......100 rnds a year? 300 rounds a year?

By coincidence, I was handling a cheep double and it was tight. I was thinking is was just "Too Damn Tight". Seems to me a double should open and close easy. I dont know from ever owning a double rifle, but in harms way, I would sure prefer an old worn loose off face gun to a new stiff one. Or over one that wont close if you get a single unburned grain of powder in the action.

I imagine a life time of 90% shooting just the first bbl might be your issue. That is a WAG guess, I sure dont know.

Like you, I await experienced opinions.

The answer to your questions is yes all of the above will cause a double to go off face.

When a rifle will go off face depends on many factors including quality,design, workmanship, metallurgy, load, bullet design, pressure ETC. Many doubles when off face do not need a hinge replacement but rather a resoulder job where the gunsmith simply fills in your hinge and then re drills it to specs.

I had a field grade Searcy in .470 a while back that I put over a 1,000 round through closer to 2,000 actually. She was still pretty solid but starting come off face just a bit when I traded her in. I've heard of some rifles coming off face within 100 rounds it is variable and hard to say which ones will and which ones won't.

The guy to ask here on AR is "H2oboy" who has probably worked on more doubles and refaced more of them than most on this sight combined.

I have put nearly 1000 rounds through my 470 heym and it still feels as tight as I remember it did when I got it.....

Mac

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I have put nearly 1000 rounds through my 470 heym and it still feels as tight as I remember it did when I got it.....

When you press the lever (word?) does the action open under the weight of the barrels or do you need to help it open with the other hand.

Once delivered, every double rifle is on its journey to being off face and needing a rejointing with replacement pin and/or tig welding. But, IMO, the leading cause of a rifle going off face before its time is poor cleaning and greasing practices.

How well a rifle is made has a huge influence on when it will come off face, but given two identical rifles, The properly cared for rifle will ramain on face a hell of a lot longer than the one improperly cleaned and greased. The may look the same on the outside, but improper cleaning and greasing will materially, significantly accelerate the wear one faces.

Every time a rifle opened, the hinge pin (the round "bridge" across the action bottom, at the front - some are removable and replaceable, some are not) and the hook (the protrusion from the bottom of the barrels with the "half" round cut which hooks over the pin when the rifle is assembled) slide against each other. No lubrication, dirty lubrication leads to wear.

When the rifle is new, the fit between hook and pin is tight, the better the rifle the tighter the tolerance and the more uniform the gap will be. Properly greased, the rifle will show minimal wear between the hook and pin from opening and from firing since a proper greasing will both lubricate the joint and act as a buffer and fill when the rifle is fired. A good reason to use top quality, high temp, high pressure grease for this application.

Every time the rifle is fired the hook rams the hinge pin. The more wear, the greater the gap between the hook and the pin, the greater the gap the more momentum the hook has when it rams home. So going off face is an accelerating proccess, begining slowly even on lower quality or poorly cleaned and greased rifles and accelerating as the rifle wears. SxS's generate torque on firing and this torque only exacerbates the problems that develop as wear grows.

Message here: Religiously clean the joint each and every session you shoot. Remove used and dirty grease and replace with clean, fresh grease. And if your shooting session is more than a good handful of rounds, take a break, take the barrels off wipe off the old grease (a patch or Qtip work well for this and store easily in a case) and regrease.

Also remember that heat is an enemy. Heat will change the dimensions of the pin and the hook differently and at different rates, so heat will temporarily widen the gap between pin and hook, leading to more wear if the rifle is fired when the barrels are hot. (Some rifles seem to tighted when they get hot, and that is equally bad since the grease is driven out, leading to wear on opening and no cushion on firing.) Really any time when the barrels and so hook are at a different temp than the action. Barrels heat first! So don't shoot them too hot and let them cool between groups or short strings of shots.

The same cleaning and greasing regimine that will take care of your pin and hook - the most important elepmants, imo - will also take care of your locking bolts and third fastener if there. The parts move against their counter parts ion the barrels and will wear. Proper cleaning and greasing will minimize that wear. In addition, they face the same battering ram effect when the rifle is fired, with the barrels trying to turn on the pin and so causing the bolts and third fastener to ram home. Think three dimensions of movement here, the barrels try to rotate on the pin so the breech end is going upward, the torque is trying to force the barrels right or left, the barrels are also trying to move forward. The grease is minimizing both wear through lubrication and movement through filling the gap between moving parts.

Hope this motivates any reader into relgiously cleaning and greasing their double rifles and shotguns!

JPK

Good stuff JPK, very informative.

fourbore.....I have to physically open it....it will not just fall open....

Mac

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Originally posted by fourbore:

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I have put nearly 1000 rounds through my 470 heym and it still feels as tight as I remember it did when I got it.....

When you press the lever (word?) does the action open under the weight of the barrels or do you need to help it open with the other hand.

Fourbore,

There are rifles that cock on opening (most) and rifles that cock on closing, rifles with ejectors will have some resistance from the ejector cams on opening as well and will cock their ejectors on closing. Either way, "falling open", or effortlessly closing are not required, or even wanted. Moreover, a well balanced, well cared for rifle may never "fall open" since its barrels don't carry their weight so far forward as a clunker and so have less leverage from just barrel weight.

In any event, it is no issue. I can assure you that in the heat of the moment, even the stiffest of rifles will be opened (then reloaded) and shut without a conscious thought by the hunter focused on his quarry.

Prior to my first elephant hunt I was concerned that perhaps my double rifle might be a bit stiff and lead to slow reloading. In reality, it never even registered as I immediately reloaded after shooting that first elephant, and it has never registered since.

Interestingly, it is the same for my SxS or O/U shotguns when duck, goose, quail or other hunting, or even at the skeet of clays field.

JPK