doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com When does dent become a danger?

I for one am unconvinced that when the Wads hit a constriction they speed up. I bet if you put a close fitting wad in that bore & push it through as fast as you can with a rod that when it hits that dent you will feel a resistance, not an easing of the force require to keep it moving. I know this is the case in pushing a wad through a choke. A checking of the wad can cause a pressure spike the same as a checking of the shot charge.
The real question is whether a dent of only .005" is enough to cause trouble, but why find out unless you just don't mind sacrificing the barrels to do so.

Bernoulli's principle applies to fluids, not solids. A shot column traveling down the bore certainly does not fit the definition of inviscid flow.

I'd fix it and then use low pressure shells.

I am yet to read any good explanation of just exactly how a shot column acts: fluid, simi-fluid, something else?? It surely isn't a solid. As a group, not as individual pellets, shot will support only minimal shear force. So, it is very difficult to consider it not a fluid. It does react to a constriction much as a fluid when it encounters the choke constriction during "flow" within a barrel. If shot did not react to constrictions as a fluid, I think choke would not work. Putting choke in front of anything but a fluid would be a disaster, IMO.

DDA

Why not fix it ? Cheap fix!

It could cause the rib to come loose, big bucks later compared to cheap repair now.

Boats

Personally I would have the dent lifted, but in the big picture I don't see a constriction of .005 at localized area any more of a danger than .035 or so (full choke) 4" further down the tube.

Being 4" from the muzzle, the pressure by the time it reaches there is down quite a bit, most of the pellets should still be in the wad and I don't see how anything like this could cause a loose rib or a blow-out.
Pattern it and see if there are many "flyers".

I agree to get it fixed and shooting lower pressure and velocity shells through it also.

Thanks for all the replies. I am looking into getting it repaired as the gun is too nice to leave it as it is...

Again Thank You to all that responded...

Have a Wonderful Day.

Don

Get yerself a bunch of steel ball bearings that will just slide inside the barrel and fire 'em until the dent goes away. Yeah, that sounds about right. Why screw around with expensive middlemen with their fancy dent raisers and tiny hammers.