I have a S&W Mountain Gun that has .427 throats, has anyone had any experience with any of the companies that will open them up? I'd like to have them opened to .431 and don't want to spend the money on a reamer. Thanks in advance.

Pat

I done my Dan Wesson 44mag with a reamer I bought at Brownells. It also had a .427 cylinder throats and sucked for accuracy. It now shoots great. This is the link if you wish to do it your self.

http://www.brownells.com/aspx/NS/store/ProductDetail.as...DER+THROATING+REAMER

If it's a matter of cost, what with shipping both ways, insurance, labor, and waiting, the cost of the reamer should be less than having the job done for you. It is not difficult as very little metal is removed. Use plenty of oil, and keep the flutes cleaned out with an old tooth brush. When you are finished, you can sell the reamer either here or on the Cast Boolits Board and get most of your money back.

Pat, Take a look at www.cylindersmith.com

Thanks all. It's not the money as much as the lack of interest in playing with handguns that makes me want to farm the work out. I do think I'll save about 40 bucks though by having someone else do it. I can't shoot a pistol worth a crap anyway and will be the first to admit it.

Pat

I believe you will have to remove the cylinder to send it to be reamed out. With my Dan Wesson I was able to remove the barrel to ream out the cylinder throats. Check with whoever you wish to take/send it to the cylinder on a S&W is not hard to remove if you have any experience or a good pistol smithing book may show you how.

I wish I could be of more help.

I have a reamer for .45 Colt and a complete set of pilots, too. Also for .38-40.

It is an easy job. You will need plenty of drilling/reaming/machining oil. You will also need to be able to remove the cylinder from the gun.

If you send it off, just send the cylinder.

Size your cylinder throats so that if you want to shoot lead bullets, you can get bullets of the same size easily. Your cast bullets must be the same size or just a little larger than the cylinder throats or you will get gas cutting. It is hard to get oversize bullets, unless you want to cast your own and then you sometimes end up buying an oversize mold.

Since most jacketed bullets are .430, size your throats to that. You can also get lead bullets that size easily. 0.001" oversize in lead bullets is just fine.

In some respects you should have a continual size down situation. That is, the cylinder throats should be (for example) 0.430". Then the grooves should be 0.429". Squeezing down is just fine. If you have the reverse setup, that is going up, accuracy will suffer. S&W grooves are hard to measure as they are 5 groove barrels and it takes special micrometers to get it right. Do your measurements and set it up correctly--it will pay dividends.

I have a 44 Cal LBT 280 gr LFN bullet that casts .432 that I shoot in my Marlin and that's what I want to use in the Smith, although at a hell of a lot slower velocity if I want my wrist and elbow to remain located in their present position with that little Mountain Gun.

I see the place Paul sent me will open the throats to .4305 and that should be perfect for a .430 bullet. I figure a 280 gr bullet at 6 or 7 hundred fps out of a 4 inch barreled lightweight should give me plenty of bang for my buck without causing brain damage. I made the mistake once of loading a 45 cal 260 gr WFN to 1050 cronographed in a 4 5/8 Ruger Blackhawk and I couldn't feel my fingers for a week, ain't taking the chance of that happening again.

Thanks again for all the help from everyone.

Pat

Why has no one mentioned honing the cylinder throats with the over-sized LBTs? Same process as opening a mold up. Go slow,and get some .430s for a drop through test. Worked well on my old security six revo and an SBH.

I think the main problem with honing is the extreme difficulty of getting all the chambers the same. Not saying it can't be done, but it takes an inordinate amount of time to do and it's too easy to make a mistake. Using a reamer is fast and consistent. The pilot holds the cutter in perfect alignment, all of the chambers come out measuring exactly the same diameter, and they don't require any tweaking or fiddling to get them all hitting the same point of impact. I put the honing technique in the "penny wise, pound foolish" category. More power to you if you made it work, and I don't mean a personal insult by my comment, but to me it's "Bubba"izing and an unnecessary risk that can too easily ruin a good cylinder.
Reamer cost:$60-80. vs. Grinding compound: $5 + shipping, and when you screw it up, cost of new cylinder (if it's not out of production and you can still get one) & custom fitting:$200-300. Value of lesson learned by doing it right the first time with the right tool: priceless.
I do agree with you that the technique is invaluable for opening up the undersized cavities of commercial bullet moulds we are too often plagued with. "Beagleing" has saved many an undersized mould from the scrap heap. To everything there is a season....

I'm sure the right personality could do a great job honing a cylinder but by the time I got done the throats would no longer be throats, they'd be funnels! Ya have to know your limitations.

Pat

After rereading the initial post I would not take on a .004 increase in chamber dia. either! My experience was with less than .001.
On the other hand, someone who orders "GRINDING COMPOUND" through the mail sounds like a pretty entertaining fella!!!!!!!
Pat I., you would have to intentionally try to make a funnel with proper honing unless you wish to spend your summer vacation on it.

Regards,
Jeff

BTW, both clyinders I honed were reemed at the factory. Casual accuracy is the order of the day.