Flex hone or ream throats?

[bruce381]

S+W 19 throats about .3565-357 or so grove about .357 want to shoot .357-.358 WW.
Low on money (christmas) save for a reamer setup $150 or get a flex hone and go slow $35?

[Don Purcell]

Do NOT use a flex hone as you will round off the edges of the throats as you move the hone in and out. Get a reamer and do it right and take your time.

[Larry Gibson]

I suggest you just shoot that M19. Contrary to what you might have read you'll be surprised how well .357 sized cast bullets will do in the .357 throats with a .357 barrel.

Don't use a hone.

Most M19 are of those dimensions and they are renowned for accuracy.

Larry Gibson

[Shiloh]

Already stated. Much mote control with the reamer. Can this tool be rented??
You can rent reamers.


Shiloh

[Mal Paso]

Reamer!

There was one for 357 being loaned out to forum members. http://castboolits.gunloads.com/showthread.php?119472-Charlie-Two-Tracks-Throat-Reamer-Time-Share

I bought the full set for 44 but others have said, if you buy direct from Manson you can choose the pilot size and not have to buy the full set of pilots.

[bruce381]

I found a rental place 4 d tools I think i will go reamer route, Shoots Ok 2-3 inches 25 yards but leads a little tho. and I can not go bigger boolit cause throats are small.

[osteodoc08]

Do it right the first time. Every time. Use a reamer or send it out. Cylindersmith still around? I know his health had been declining. I hope he's still alive and kicking.

[jmort]

Cylindersmith still around?

Yes, but he will only do .45 Colt
http://www.cylindersmith.com/

For the $$$ he is more than fair.

[MT Gianni]

Shoot it and shoot it some more. You cannot improve what you don't have a baseline for. If it is a shooter how much more so you want. They are no longer making K frame 357's and most I have shot, shot wll.

[bruce381]

Shoot it?? baseline?? I have owned it over 37 years shoots Ok as i said but leads a little with in 50-100 boolits and shoots at best 2-3 inches off a rest. Just got it out again and wanted to try to improve it.

[leadman]

Leading could be from another source other than the throats. We need more info on your alloy, lube, hardness, powder, sizing, velocity.

['74 sharps]

Check the LASC website for the causes of leading as a hard alloy at low pressure is one cause. Once the metal is gone from the revolver, it's gone.

[Larry Gibson]

Leading could be from another source other than the throats. We need more info on your alloy, lube, hardness, powder, sizing, velocity.

+1. K frame .38s and .357s were the mainstay when I was LEO firearms instructor and armorer. Never found a single case where the leading was caused by too small throats; it was always the from the ammo used. I also note from your OP that you want to shoot WWs(?). WWs these days in many cases have notoriously little tin and 3+% antimony. Thus what you se as "leading" may actually be antimonal wash. Suggest adding 2% tin to the WWs and if straight COWWs then you might add 30 - 50 % lead to that for a much better alloy for most .38 SPL/.357 Mag bullets.

As leadman stated what lube are you using? What sizing? What powder and load? Also what particular cast bullet?

Larry Gibson

[chboats]

PM sent
Carl

[detox]

Your S&W throats should measure .3575". Most people do not have the tools to measure cylinder throats correctly. I used a +.3570 pin gauge to check mine (this is a $4.00 tool). I also used telescoping gauge and .0001" micrometer. All mine appear to be very close to .3575.

Lead slug and dial caliper will not be accurate and consistant

[MBTcustom]

Seriously, try a different alloy and a different boolit design. I highly recommend the heavy boolits loaded in 38 special. RCBS 35-200-FN and Lyman 358430 will absolutely astound you. I have owned that same gun, and if it just won't shoot, all you need to do is run about 50 boolits that have been rolled on a steel plate that has 400 grit lapping compound in it. That would probably fix it up perfectly.
If you buy a reamer, you can certainly fix the cylinder, and you can rethroat the barrel, but there are many ways to mess that up, and go too far if you don't have access to the proper tools, and the lapping compound is much easier on the gun and can cure many ills.
Just a few suggestions.

[detox]

Here is a good article about sizing and lapping.
http://www.gunblast.com/FerminGarza-Firelapping.htm

[fredj338]

I did my RBH on a commercial flex hone, very happy with the result. A hand held, reamer is probably better.

[fredj338]

Your S&W throats should measure .3575". Most people do not have the tools to measure cylinder throats correctly. I used a +.3570 pin gauge to check mine (this is a $4.00 tool). I also used telescoping gauge and .0001" micrometer. All mine appear to be very close to .3575.

Lead slug and dial caliper will not be accurate and consistant
The problem is the throat dia are all over the place, depending on when it was manuf. There really is no "should be".

[bruce381]

lot of opinons here I like that makes me think. Have offers for a laoner and will be doing that.
Alloy used all over the place for 35+ years from lino to WW sized from .356-.358 all shoot only 2-3 inches.
All lead at beginning of rifling. Used lyman, lee and saeco boolits with LARS BAC and 50/50 alox, ALL lead.

I miced various slugs that would easliy push through the throats and .357 is largest that will "pass".
Not as smart as you guys but have been doing cast boolits over 37 years in my pistols so not a newbie.

I can say worst leading was boolits with a lyman .357 sizer but came out at .3565

bye the way the "leading" is more like a lump smeared into the groves starting right at the leade.

[bruce381]

oh yeah WW with enought tin to case sharp, cast hot frosty air cooled, tryed .356-.357 and now .358 size.
231 or bulleye 4-4.5 gr in .357 cases. laod is light and maybe need a slower powder?

[1bluehorse]

Check the LASC website for the causes of leading as a hard alloy at low pressure is one cause. Once the metal is gone from the revolver, it's gone.


Excellent reading at that website....rent or buy the reamer, make sure you get the right size pilots so you're sure of the proper fit....ream the cyl. throats to .358 (will probably come out more like .3585) bullets sized to .358 should make for a "snug" fit. Check the bore for "tight" spots also....if present, firelapping them out isn't difficult, tedious and a bit messy, but not difficult....just follow directions...ream the undersized cylinder throats before firelapping a bore though...otherwise most of the lapping is done at the throat, and you'll have an undersized, abrasive bullet running down the bore....not good.....all the "don't do it", "you'll ruin it", "you can't replace metal", we're only talking about a thousandth....for firelapping, if needed, I'd recommend Marshal Stantons kit, over on Beartooth Bullets....very good read there on firelapping also....I've reamed cylinder throats and firelapped over 15 Rugers revolvers, and a couple Uberti 357's.....every one of them had improvement in accuracy and leading was virtually eliminated.....

[MtGun44]

IME, S&W K frame throats are NOT "all over the place". Their .45 Colt and .45 ACP, YES! They did
some amazingly bad things on those, but I have never seen a K frame (other than Victory models)
that didn't have good dimensions.

Another vote for spending some time on testing different boolit designs, lubes and powder charges
prior to the reaming or fire lapping.

Bill

[MBTcustom]

^^^^^^Truth^^^^^^

[MT Gianni]

oh yeah WW with enought tin to case sharp, cast hot frosty air cooled, tryed .356-.357 and now .358 size.
231 or bulleye 4-4.5 gr in .357 cases. laod is light and maybe need a slower powder?

Do your groups tighten up with jacketed bullets? If not then the "restriction" is probably not the cause of the leading.

[bruce381]

do not know only shoot cast never have loaded any J bullets

[detox]

oh yeah WW with enought tin to case sharp, cast hot frosty air cooled, tryed .356-.357 and now .358 size.
231 or bulleye 4-4.5 gr in .357 cases. laod is light and maybe need a slower powder?

Bullseye or 231 with a "true" .358 size air cooled soft bullet should prevent or reduce gas cutting. Do not exceed PSI to bullet strength...start low then work up. Is your gun spitting lead from barrel / cylinder gap area?

BTW a Hornady jacketed 357 bullet will slip fit with slight resistance thru all my .3575 cylinder throats.

[DougGuy]

What's the forcing cone look like? I find an 11° cone that is smooth and extends about 2/3 of the caliber diameter into the barrel works very well for cast boolits in many guns. Oddly enough I also found that shooting 50%ww + 50%pure + 2%tin in my SBH was the cat's meow as the gun took a real favor to this alloy. I have zero leading at the leade, and only a tiny bit under the front sight of a 7 1/2" barrel, and the best groups it has ever fired. Maybe in addition to getting the throats evened out, look at the forcing cone and try a softer alloy?

[bruce381]

thought about throats but wanted to only screw up one thing at a time:grin:

[geargnasher]

Bruce, I'll get the reamer to you but might not be 'till Monday, I'm sharing transportation with my wife while the body shop is picking deer parts out of the other one. I'll try for tomorrow if I get permission from a customer to road test across town to the P.O.

Gear

[bruce381]

thanks gear no hurry