S&w

[Rex]

Today I emailed S&W asking what to do about my 686 that leads the first half inch of barrel with any lead bullet load I use. Explaining what I have tried and loaded in my revolver. Got a reply just now saying that S&W only approved SAMMI spec factory ammo in their guns!
Guess I need to buy something else if I'm going to continue reloading!
Rex

[gnostic]

What size are your bullets? Under .358 will most likely lead the barrel. I think all firearms manufacturers will say the same thing about handloads and I think it can void the warranty. My 686, model 19 and 28 all shoot bullets sized .358 without leading the barrel. You might want to drop a .358 bullet through the cylinder, it should be a snug fit...

[Rex]

Mine won't. Lead always starts on the same rifling located at 7 O'clock in the barrel. I've shot commercial and my own bullets, no difference.

[Outpost75]

You need to have a gunsmith inspect your barrel with gage pins for "thread choke." This is a constriction of the barrel shank at the root of the thread, caused by over-torquing the barrel when assembled into the frame. Very common with S&Ws.

It can be fixed by lapping.

[Froogal]

Today I emailed S&W asking what to do about my 686 that leads the first half inch of barrel with any lead bullet load I use. Explaining what I have tried and loaded in my revolver. Got a reply just now saying that S&W only approved SAMMI spec factory ammo in their guns!
Guess I need to buy something else if I'm going to continue reloading!
Rex

I have a Ruger SP101 that does the same thing. I now shoot only jacketed bullets. I save the cast lead bullets for guns that are more fun to shoot.

[Rex]

Who has tried fire lapping and what kind of luck have you had?

[Outpost75]

Who has tried fire lapping and what kind of luck have you had?

Casting a lead lap in the barrel gives you better control of the process. My experience has been that fire lapping tends to cause forcing cone erosion more than lapping the tops of the lands where you want to remove the constriction.

When I worked at Ruger we used a round hole broach to correct thread choke. This was a cylindrical tungsten-carbide plug 0.0005" less than minimum bore diameter, which was six times as long as its diameter, having its end ground to a sharp edge and the plug being threaded onto a push-rod handle.

The bore would be swabbed with cutting oil, the plug inserted gently into the barrel and advanced by hand pressure only until the constriction could be felt. The frame was then clamped vertically in a fixture and the plug forced through the bore with an arbor press until it emerged out the barrel, the carbide plug would then be unscrewed, the push rod withdrawn, and the bore wiped and checked again with Go/NoGo pin gages threaded onto a rod handle.

This method shaves only the tops of the lands to remove the slight constriction. Done properly, it produces a mirror finish. Hundreds of customer service returns were repaired in this manner and we never got one back after repair.

[RED BEAR]

I can't see any way that they could tell you why a particular gun leads without looking at it. There are so many variables that its impossible. They don't know what alloy you use what mold what you size them what lube you use what powder how much powder ect. Sometimes you just have to play with a gun until you get everything right. It can be a rewarding experience.good luck hope you get it figured out.

[Rex]

Think I have it figured out. I've got a 358156 G.C. mold.

[Warhawk]

Howdy Rex, I see that you’re in Paxton, Nebraska. Is Ole’s Big Game Lounge still in operation? The place was recommended to me and I’ve been back every time I’m out that way, but it’s been several years since the last time.

[Wheelguns 1961]

You need to have a gunsmith inspect your barrel with gage pins for "thread choke." This is a constriction of the barrel shank at the root of the thread, caused by over-torquing the barrel when assembled into the frame. Very common with S&Ws.

It can be fixed by lapping.

This! Check out chapter seven of Glen Fryxell’s work from ingot to target.

[Rex]

Warhawk, their beer is still cold and their meals good. Also a very good "sandhills bar and grill" across the street from them called Windy Gap. Best prime rib every Saturday night for $19.95. You get your own silver, drink (unless from the bar) and make your own salad. They bring you the steak and taters.
You come this way, give me a call, I'll treat.
Wheelguns, I suspect you are right. Good gunsmiths (or bad) are a little thin out here in the sticks but I will take a look for one.
Thanks,
Rex

[mdi]

For shooting any lead bullets in any gun you gotta know the gun. Measure the cylinder throats and slug the barrel. Normally leading in the first part of the barrel is from bullets too small and often too hard. Use bullets the same diameter as the cylinder throats as a starting place (smaller bullets often lead and larger bullets are swaged down as they pass through the throat). If the cylinder throats are smaller than the barrel groove diameter the bullets will lead the barrel. Many commercial cast bullets are "nominal" diameter, and often too small for many guns, so you need to measure the bullets too. Also, most commercial bullets are unnecessarily hard and have a so-so lube. I would measure the throats and bbl., use a 10-12 BHN bullet with a good lube and see what happens.

I'm not sure if any gun manufacturer will OK the use of any handloads in their guns; voids warranty...

[Rex]

Drive a soft lead slug through my throats and by my Chinese micrometer they are .357. I've slugged the barrel but I can't get a good mic reading on the diameter, somewhere around the same as the cylinder throats. Son-in-law's Highway Patrolman doesn't lead with the same loads.