badly rusted bores?

[Merle]

Greetings,

I am about to start reloading for several rifles with bad bores.

I wondered if anyone has ever experimented with different bullet types to see which works best.

My hunch is that long, heavy, jacketed round nosed bullets driven fairly slow (more or less at cast bullet velocities) would work the best. The long heavy bullet should give the most bearing surface & the low velocity should minimize bullet stripping in the (now shallow from rusting away) rifling. I don't think that cast bullets would work well with a lot of pitting present - too much fouling.

Any experience, or thoughts?

Thanks.

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[K31]

How badly pitted? If the pits are too deep, it could be dangerous to shoot. A really rough bore raises pressures.

[desporterizer]

I have had good luck with cast & rough bores.

[K31]

In my experience, a bore that looks pitted, but feels reasonably smooth when you run a patch through it, will shoot cast bullets alright. If it rips little pieces of patch out, forget cast bullets. A bore that rough also rips up jacketed bullets, and might be improved by lapping.

[Merle]

How badly pitted? If the pits are too deep, it could be dangerous to shoot. A really rough bore raises pressures.

The pits aren't that deep. It is a pretty even amount of rusting - no serious pits. I have fired all three of them with surplus, or handloads equalling military loads with no problems except poor accuracy. Mostly it has rusted to the point the rifling is now very shallow & rounded. I'm getting keyholes at 25 yards.

I am referring to three rifles. A Steyer M95 in 8x50R, a Carcano in 6,5mm and a Hakim in 8x57mm. They are all pretty much the same for bore condition. I'm not expecting miracles, just hoping to be able to shoot to 100 yards and get something resembling a group.

Thanks

[Merle]

I have had good luck with cast & rough bores.

I have been reluctant to try cast. I thought it would leave too much of the bullet in the bore, and damage the bullet too much for good accuracy. I also thought that cleaning would be a real problem. If it works for you, maybe I've been too hasty. I'll give it a try - I've got nothing to lose.

PS: I have been told by one person that he shoots a few cast bullets to "fill in the holes" then switches to jacketed. That might work, if there is enough rifling left.

[Merle]

In my experience, a bore that looks pitted, but feels reasonably smooth when you run a patch through it, will shoot cast bullets alright. If it rips little pieces of patch out, forget cast bullets. A bore that rough also rips up jacketed bullets, and might be improved by lapping.

I never thought about the patch test - thanks. Shame on me!
I would have to be very careful about lapping - there isn't much rifling left as is.
The Carcano is the worst for shallow rifling.

[gandog56]

I would think about trying some firelapping.

[buffdog]

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First of all...really clean the bores. Cast bullets do not shoot well if any copper fouling is present. Do not shoot cast bullets, then jacketed bullets or vise-versa without a thorough cleaning between firing the two types. Copper fouled bores will really open up groups.

Fire lapping was mentioned in another post. Basically, fire lapping is taking a cast bullet, coating it with an abrasive material, and shooting a few through the rifle. You then clean the bore, load a few more cast bullets using a finer abrasive material, and fire them. Clean again, repeat the firing with even finer grade abrasive material, and clean again.

You can also lap a barrel using a cleaning rod and pouring a lead lap onto the end of the rod. I have used this method successfully in improving a bore. You have to put a patch on the rod about 6 inches from the tip, put it into the bore from the breech end, leaving the tip about one inch inside the muzzle. You then pour melted lead into the bore from the muzzle end, leaving about a 4 to 6 inch lead slug on the rod. Tap the rod so that the slug moves about 1/2 inch out of the muzzle, leaving the large portion of the slug in the bore. Trim off the excess lead, then move the rod out to expose about 2 inches or so of lead. Coat the lead with the abrasive, then carefully swab the bore back and forth about 15-20 strokes. Make sure the lead lap DOES NOT COME OUT OF THE BORE. If it does, do not try to put it back by aligning the grooves...cast another lap. Repeat as in fire lapping with progressively finer abrasive materials.

You will probably feel a few places in the bore where it is harder to push the lap. Give them a few shorter strokes in that area. These are tight spots in the bore. After a bit, you will get an even pressure on the rod all the way through the bore.

There are kits available that will give you the proper size of abrasive material. DO NOT, ABSOLUTELY, DO NOT USE AUTO VALVE GRINDING COMPOUND. THIS STUFF IS WAY TOO COARSE, EVEN IN THE FINER GRADES, AND WILL REALLY RUIN YOUR BORE.

Light pitting is not really a problem. Many of these old military rifles really can shoot well with cast bullets. The big thing is to make sure the bores are really clean and do not mix up jacketed and cast bullets at the same firing.
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