Canadian Issue No.4 rifle barrel vice photos

[jss]

The best ones we had were made in the Base Workshopos machine shops and had two handles and even then, there were a couple a xxxxing great big pipe-like tommy bars to give extra leverage.
We had un breeching and breeching up down to a fine art. But be warned that if you overtighten, you WILL get a (an almost invisible) chamber bulge

Sounds like a lot of force would be applied by this tool. Would the bulge from overtightening by any chance be in the form of a ring at about the point where the threads meet the reinforce, the weakest point, as observed and not fully explained on a two or three No4's?.
If not, is it possible to recognise this "bulge" or other signs of overtightening that could stretch and fracture the chamber at the weakest point, and possibly go un-noticed?. What usually gives when you over-tighten?.

[tbonesmith]

Without wanting to argumentative or nit picking, but rather to establish in my own mind how tight we're talking, would factory set up Savage or Longbranch rifles ever develop this bulge? or is too tight even tighter than these typically "frightfully tight" factory jobs?

[Peter Laidler]

I don't know how LB or S tightened the barrels but there is a finger tight underturn figure and a final torque figure. I breeched up a really tight No4T once and far exceeded the torque and within a week, it was back with hard extraction problems and the spent cases showed the little bulge at the point where the chamber aligned with the breeching up point. I knew what I'd done immediately - but didn't admit it of course......... The next barrel was also tight but by skimming a gnats knacker off the face of the body (on the basis that two barrels wouldn't be wrong ?..............) to get the correct 17 degree (? from memory....) underturn it went on perfectly. Chs was easily corrected

On the other hand, some barrels would almost unscrew by hand with the merest tweak of the barrel clamp. But get a tight basxxxx and it's hard work

[Demo]

Were the factory barrel clamps designed to clamp on the knox form part of the barrel or the tube, like sons.

[Peter Laidler]

Definately NOT the tube...... They utilised the knox form as the medium for breeching up

[Brian Dick]

The bolt keeps the receiver rigid to keep it from "springing" if excessive force is needed to remove a barrel. Most are no problem but every once in a while..... I had a Savage defeat me once. I couldn't get the barrel out without cutting the shoulder on a lathe and the customer wanted the spare barrel so it just didn't happen.

[Surpmil]

Once saw a No1 actually twist the barrel before it broke free. 1920s rifle and barrel.