Grrr... Rifleing

[bang]

Bang,
What you are doing is actually not lapping, it's freshing a barrel. Not a new or unknown procedure. This was done by many gunmakers to do what it is called, freshing a partially worn barrel to extend its longevity. I have a rifling machine dating to the late 18th century and about 150 different freshing heads that were used with this machine. My theory is that barrels were not cheap or readily available so even small bore rifles were made out of larger than needed barrel blanks to give them the ability to fresh or drill out and re rifle barrels as needed.
Mark

Didn't say it was. Said I took lapping to a step further.

 

[Bad Karma]

Didn't say it was. Said I took lapping to a step further.

It certainly does!

 

[wb78963]

It certainly does!

Hello wodenbow,
I have an idea on HOW a barrel is freshened, but that is way yonder out of my pay grade.
Regards
Bunk

 

[Bad Karma]

Hello wodenbow,
I have an idea on HOW a barrel is freshened, but that is way yonder out of my pay grade.
Regards
Bunk

Mine too... I spose I might try it out of desperation but somehow I don’t think it would work out as well as it did for Bang!

 

[Dude]

I saw a youtube where a guy fire lapped his BP gun by rolling the bullets in varying grades of grit. He rolled them between two flat pieces of steel impregnating the lead with the grit. He'd shoot three shots of the course grit, clean, three of the medium grade, clean, three of the lightest grade abrasive and then clean really well.

I wish I'd know bang's trick last month - I had a gun that really could have used that process.

 

[TFoley]

Over in the USA there is/was a company that made coated bullets of the kind that we shoot in unmentionable firearms. They were made up into cartridges, loaded and fired the requisite number of times until the required degree of polish was obtained. The coating, IIRC, was kind of ceramic abrasive of varying degrees of abrasion, but were, in any case, VERY fine even to start with - something like 500-600 grit - going right up to almost totally smooth. They were also quite costy.

 

[kansas_volunteer]

Personally, i consider most of the above described methods second bests. I use a lead lap poured around a rod and charge it with lapping compound as sold by Brownells. The rod I use is basically just an oversized cleaning rod made using the front hub from a bicycle and a greater-than-barrel-length mild steel rod in place of the axel. My first lapping job was done to a T/C Hawken. Running the lap throught the barrel (after pulling the breech plug) i found tight spots and rough spots that were all polished smooth. The barrel had already been shot hundreds of times. The shooting did nothing to improve the bore, but the lapping did. It loads very easily. The PBR slides effortlessly down the bore and it is accurate enough. If you dont want to pull a breech plug, or lap a barrel before breeching then some of the methods described above might help a little bit, but none are a substitute for doing the job with a poured lead lap.

Some rant against pulling a breech plug, but if the breeching is done in a way that makes removing and replacing the plug dangerous then something else is wrong.

 

[sawyer04]

What you are doing is actually not lapping, it's freshing a barrel. Not a new or unknown procedure.

This is correct terminology, to lap a barrel I pour a lead slug in the barrel on the end of a steel rod and after it conforms to the rifling I use valve grinding compound to polish the bore, this method of freshen the bore it is possible that a different diameter bullet has to be used or thicker patch.

 

[Dude]

I've got questions on making the lead slug. Do you position the steel rod in the bore somehow, then pour molten lead into the bore? How long is the slug? How do you block the bore?

How exactly do you make the slug?

 

[rich pierce]

Use a wooden rod close to bore diameter. 2” from one end file a groove around it and wrap string in the groove till it is enough to form a tight seal in the barrel. An eighth inch above this file a square section to within 1/4” of the end of the rod. Slide the rod down through the muzzle until the square section is barely below muzzle. Heat the barrel to sizzling. Pour molten lead in till it tops up. Trim as needed till it will slide.

 

[Dude]

I get the picture - that shouldn't be difficult. One question, though: how long do you make the slug? An inch? Two?

How long is this wooden rod? Longer than the barrel? Just long enough to make the slug and attach to the ramrod?

Let's see if I understand you:

1. Select a wooden rod close to bore diameter
2. Length?
3. Close to the end create a seal with wrapped string
4. 1/8" from the seal, file a square section about 1.5" long
5. Place in preheated barrel and pour in lead
6. Trim excess till it slides down the bore.

 

[rich pierce]

I get the picture - that shouldn't be difficult. One question, though: how long do you make the slug? An inch? Two?

How long is this wooden rod? Longer than the barrel? Just long enough to make the slug and attach to the ramrod?

Let's see if I understand you:

1. Select a wooden rod close to bore diameter
2. Length? 8” LONGER THAN BARREL
3. Close to the end create a seal with wrapped string
4. 1/8" from the seal, file a square section about 1.5" long
5. Place in preheated barrel and pour in lead
6. Trim excess till it slides down the bore.

Make the square portion an inch and a half to 4” long. The longer it is the further you’ll need to heat the barrel.
It takes quite a bit of fiddling to get the lap to pass through the bore after removing the flash. On first attempts pull it from the breech end or use a short starter to tap it in a bit. Tap it back out from the breech end. See where it’s super shiny, rubbing off. Scrape or file with needed files (it will clog them). Use oil. Take your time with this part.

 

[LME]

Use a wooden rod close to bore diameter. 2” from one end file a groove around it and wrap string in the groove till it is enough to form a tight seal in the barrel. An eighth inch above this file a square section to within 1/4” of the end of the rod. Slide the rod down through the muzzle until the square section is barely below muzzle. Heat the barrel to sizzling. Pour molten lead in till it tops up. Trim as needed till it will slide.

I agree with your method of lapping a barrel. I think it wise for anyone trying to lap a barrel to read up on this process.
The length of the plug is important and better not be to long!