Rifling polish & smoothing methods?


Harve Curry
December 17, 2006, 03:48 PM
I have a Marlin 45-70 relined and I can see where the lead accumulates on the lands. The rifling appears like some polishing would help.
When the barrel is clean I have squeezed out 1 1/2" groups at 100 yards with my handloads on not much special attention paid to them. But it leads up fast and accuracy drops off after 4 or 5 rounds.

I've heard of shooting a slug with fine abrasive powder imbedded on it and also just shooting abrasive powder through a barrel.
So my question is what methods of polishing has anyone had experience with?

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December 17, 2006, 03:52 PM
You can do what I have done. I take a poofy, cotton barrel swab, wrap it in ultra fine steel wool and run it back and forth, lubed, through the barrel.

December 17, 2006, 03:58 PM
eww, dont use abrasive powders. use hoppes solvent or whatever brand you like and a brass brush. lead doesnt need that much scrubbing to be removed. let the solvent sit for a hour or two and let it do its job. avoid steel if you can. polishing the rifling will just accelerate wear and you will lose accuracy faster.

if you do the steel wool trick, make sure its ultra fine wool. odds are the barrel will come clean with just brass brushes.

Harve Curry
December 17, 2006, 04:11 PM
Cleaning it has been easy enough, the lead comes right out. But I thought there was a way to polish it so it wouldn't lead so fast. I use WW lead dropped into a can of water, hot from the mold for bullets and SPG lube.

But I wouldn't want to polish it if would reduce accuracy.

I thought it would improve it or be the same.:confused:

December 17, 2006, 06:46 PM
To smooth out a rough bore, there are several methods.

1. Buy some JB Bore Paste and use it on a patch to clean and polish the bore.

2. Buy one of the "fire-lapping kits". This is a kit that contains various grits of
special non-embedding fine abrasives that are used to coat bullets.
The bullets are loaded using light powder charges and fired.
After firing several rounds, you go to the next finer abrasive until the bore is smoothed out.
The kits come with loading instructions on what powder charges to use.


3. Buy jacketed bullets and use a barrel break-in program.
This usually involves shooting one round, then cleaning the bore.
Fire another and clean, and repeat for 20 rounds rounds or so.

Then fire two rounds and clean for 20 rounds or so.
Then 5 rounds and clean for 40 or 50 rounds.
This also smooths out the bore.

I do NOT recommend using steel wool, or any kind of ordinary grinding or lapping compound. These will round off the edges of the rifling and degrade accuracy and barrel life.

.38 Special
December 17, 2006, 08:15 PM
dfariswheel hits it right on the head, except we'll disagree on the value of barrel "break-in".

I would go with door number one, were I you. I use JB for all my bore cleaning and with time you end up with a very slick bore. If you are in a hurry, fire lapping can be effective, but you do have to use a bit of care and know -- KNOW -- how to slug your barrel, check bullet seating/chamber depth, and use the micrometer accurately. The big difference between JB on a patch and fire lapping is that fire lapping can be overdone. Too many coarse pills can move your leade foward enough that accuracy goes out the window.


Harve Curry
December 17, 2006, 08:34 PM
Thank you all for sharing the 'know how' .
I'll try the JB bore paste first.

Jim K
December 17, 2006, 08:38 PM
Are you using gas checks on those lead bullets? If you aren't, the heat from the burning powder will melt the lead of the bullet base and cause heavy leading even in a smooth barrel.


Harve Curry
December 18, 2006, 08:11 AM
No gas checks, the Lyman mold I have is the 330gr Gould style hollow point, which on that bullet is more of a way to get weight down. I have a friend nearby who I'll ask to take a look at it, get his opinion of what you suggest.

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