Run some brass cleaning rods down the bore a few times then check. I dare say it's had its day so a wanted ad maybe the best option. Mach 1.5
How far does the cleaning rod go down the barrel? Mach 1.5
Theres ways to improvise with more common house tools, keep condiering making a crude lathe myself but not got past the thinking stage yet, grinding wise you can use a dremel/rotary tool, you'll have more clean up maybe and need to be steady but it can be done.
Failing that somone here may probably help if you send the parts to them.
You'll Shoot your eye out Kid
Currently looking for an SMK/BAM B4-4 Rear sight or help modifying current one.
Blockage is around 4in from breach and seems around 1in thick, judged by rod from muzzle. Ive cleaned no end of dust, con webs and milled grain from inside the rifle. I think some of it has settled down the spout, absorbed water and swollen/rusted into place. I'm between knocking a simple electrolysis bath up or going for phosphoric acid bath. Potentially, the phos-acid me dissolve the blockage too.
Oh right..perseverance or a new barrel. If you need any other bits for an 80 give me a shout as i have a few but i dont have any barrels. Mach 1.5
Looking at the breech and muzzle i wouldn't waste any more time on the barrel. Wait for a s/h one or if you want to make a nice custom you'll probably have to buy a new 20 cal. If the cylinder isn't pitted as bad as the barrel could make a mint custom gun. My favourite 80 started off life a a rough old thing but wasn't pitted as bad as your barrel. Got a Colin Molloy re blue and a custom stock now, looks mint.
Plinkerer and Tinkerer
I think it'll be alright to put in your Signiture too if you want as several of the lads have wanted bits in theirs, that way you'll get more reach as it'll hopefully jog someones memory and they'll have a cheap one in their spares for you.
You'll Shoot your eye out Kid
Currently looking for an SMK/BAM B4-4 Rear sight or help modifying current one.
Wash well in petroleum product, kerosene to remove as much oil/grease as possible.
Electrolysis is good, easy and works well.
Also is soaking in a container of tea- take bags or spoons of the cheapest tea and make a brew that will fit the container(preferably with a lid) - soak for a week then check, re soak if required.
To clean the bore.
Clean with wadding and or a brush.
Depending on 0.177" or 0.22". Use a suitable size brass welding rod (non flux ); pein the end then hammer in from the breech end; repeat until no more gunk comes. The peined end will shape to the rifling and will not harm. Repeat the peining as needed.
If the rifling is a little suspect, treat with graphite powder.
Best of luck
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