A question about danger...

[Brian Dick]

Check and scrub the chamber. It could have pitting that's causing hard extraction. I recently had a guy here with a No.5Mk.1 that had a small but relatively deep ring of pitting in the chamber just behind the shoulder. No amount of polishing would eliminate the problem as the brass was expanding into the pitting making primary and secondary extraction impossible without a couple of taps with a plastic mallet. Needless to say, I couldn't fix it. It needs a new barrel.

[mike16]

the brass is new or reloads? Do you know how many times the brass has been fired? take yor brass and rifle to a 'smith for inspection

[am1958]

Mike16:

The Portuguese brass seems original and quite old. That's the only brass I've fired through this rifle.

Brian:

I took a magnifying glass and a powerful light to the chamber... What I found was "odd" since I'd given the rifle a rudimentary cleaning after I fired it.

The barrel looks unpitted but the chamber had something I'm unsure how to describe. Excuse my attempt at describing it. It seemed to be wiggly calcium deposits something like I have in my marine aquariums in the past... Look at the images here.

I put a copper brush through the chamber followed by a general cleaning of the chamber and now I'll see what happens - I'll polish the brass too...

It may be a while until I get to shoot again though...

[Brian Dick]

I'd guess you've found the problem. Even a lightly pitted chamber can cause hard extraction. Give it a good scrub with an oversize brush and try it again. If they are still sticking, you may have to gently polish it a bit to cure it.

[mrclark303]

Just an idea, I am not a gunsmith in any way, just a keen amateur trying to understand as much as I can..

This is probably a stupid idea and I am sure there's a good reason not to do this .. would it be possible in the event of very light chamber pitting to clean, "key" and fill the pits with a hard resin of some sort, then polish the chamber??

[RobD]

Here's how I'd polish the chamber: I'd get a fired case, cut it down below the shoulder, drill a hole through it, put a wooden dowel through the hole so it sticks out about 12 inches behind, smear some brasso on the case, put it in the chamber, and twirl the wooden dowel. Rinse and repeat until the chamber is polished. I'm sure there are smarter ways...

[Parashooter]

Here's a practical way to polish a rough chamber with commonly-available tools and materials -



Start with 400 or 600 grit. Finish with 1000 or finer. Turn rod with hand brace or power drill at low-medium speed, using light pressure and plenty of thin oil for lubrication. Don't overdo.

[browningautorifle]

The way Parashooter shows is the way. I use a wood dowel though, and oil. Don't be cheap with the paper and don't over do.

[Parashooter]

I got tired of replacing broken wood, tried the brass rod and never looked back.

[Peter Laidler]

You can polish it all you like. Some call it grinding it away. But that's all it is and as you're grinding away along a taper, the mathematics of that route takes it from what the technical people call 'a knackered chamber' into an '.....even more knackered chamber'. Just my opinion of course, based on nothing more that simple maths in this case!