Throating some Winchester levers?

[Canuck Bob]

I am seriosly considering doing a throat ream to my Winoku 32-20 92 and 32 Special pre-64 94. Both rifles will be for cast but will shoot j bullets too.

They have the typical sharp ramp from end of chamber with no freebore or ball throat.

Considering 2 thou over bore for a short freebore to a 1 1/2 degree leade ramp to bore diameter. This seems to be a decent standard for cast shooting.

I have machine shop experience and have a Southbend lathe at my disposal. I will hand ream though.

Any advice on tools, methods, or tricks?

[uscra112]

There was an excellent article in Am Riflemen on rethroating for cast, by Ed Harris. Sometime at the end of the '70s I think. P/M me and if I can find it I'll scan it for you. He made a specific recommendation based on his .30-30 cast boolit rifle, and I'm sure that would carry over to the .32 Special. Keep me posted on the .32-20 - I've got one of those, too.

Key factor will be to make darn sure your reamer's pilot fits the bore exactly. Otherwise you'll probably ream off center, and the rifle will never shoot well.

I'd be worth the few dollars for some pin gages from www.gageshop.com to actually determine your exact bore(s). Six pins at $2.50 each would be cheap insurance.

I dodged that bullet when I rechambered a Contender barrel to .357 Max. The SAAMI .357 Max drawing calls for a .3465 pilot, (?? why ??), but my barrel is .3500 bore. Dave Manson kindly made my reamer removable pilot, and supplied the right bushing.

[MtGun44]

I agree that a replaceable pilot bushing closely fitted to the bore will be a key thing to
get a straight throat.

Bill

[Canuck Bob]

I went to the gage site. I have slugged and am willing to get gages. How do these sizes work. It shows a gage to a thousand and a gage to a half thousands with plus minus references. Never worked with these gage pins before?

Edit: Got it rougly figured. the gages are on the english size for three decimals and also at 5 tenths. Minus is to note direction of tolerance. So if I wanted to measure the bore that is .321 I cold pick up a 3205, a 321, and a 3215 minus for accurate checking. Then order the pilot or pilot bushing to the size that fits. Am I missing something?

Would a breech end chamber bushing be worth the time to maintain the reamer center to the chamber?

[nanuk]

I believe the plus minus are the tolerances.

get the minus, as it has to be a hint undersized to slip fit into a bore of the stated size.

ie/ a .5000 pin will not fit a .5000 hole. You need a .4997-.4998 pin

that is what I understood and it was recomended to get the "minus" pins

[Canuck Bob]

Mountain molds has an article on throating levers.

http://www.mountainmolds.com/helpRifle.htm

[MtGun44]

The pins in minus are .0002 smaller than the marked diameter, so will JUST go into
a hole of the marked diameter. You want the minus pin gages for measuring holes.

Bill

[uscra112]

Correct, in that a "minus" pin will go into a hole that is dead on the nominal value, or larger. If using a "minus" pin that is nominally .0005" larger you find that it does not go, you have narrowed the range of possible values for the diameter down. Having also a "plus" pin for the smaller size give you a little finer resolution to the test. Instead of steps of .0005", you have a pin in between that gives you a little more information.

Probably overkill for what you're trying to do there. But that's in my nature.