S&W 29-2 Tolerances?

[insanelupus]

I'm curious if anyone has a S&W 29-2 and what their tolerances are. Specifically I'm wondering what the groove diameter, chamber mouths, and the cylinder gap are.

I've had occasion to measure a 29-3 and a 629-3 and found the chamber mouths to be so grossly oversized (0.4340") it is ridiculous. Both owners asked about using cast bullets. I know each firearm is a rule unto themselves, but with groove diameter hovering around 0.429" I advised them to shoot jacketed and enjoy them.

On another occasion I've measured a 27-2 which was made in the late 70s and it was spot on, groove diameter and chamber mouths were within 0.0015" of one another, plenty close enough to work with and enjoy.

I'm going to look for a 29-2 and think I'd like an earlier S prefix model, but I'm curious how the tolerances were for the N prefix serial numbers. I suspect they will be better than the 29-3 and 629-3 I've checked in the past.

I definately want the 29-2 for the pinned barrel. I know barrels aren't supposed to turn in the newer ones, but I know of at least one which did. I also want a blued model so if I ever need any smithing done, the smith wont' be fighting the nickel finish if I need any welding, etc. The pre 29s and 29-1s are getting more scarce and have enough collector interest, I don't want to purchase one. I want to pack one in the mountains and plan to use 250-270 grain bullets at about 1050-1150 fps from the 4" barrel. I'm not shooting mastadons so that should suffice for my needs.

If anyone has the specs on their revolvers and are willing to share them, it would be appreciated. I'm hoping to be able to see if there is or isn't a significant difference between the S and N prefixes in the 29-2 model. Thank you.

[rockrat]

Can't help you there, but I have a Colt New Frontier, in 44sp. that has .433" chamber mouths and a .429" bore. I shoot .433" boolits thru it with good accuracy.

[Rico1950]

I have 2 N prefix 29-2s, Bores are .429", cylinder throats are .430" & .431".
I'd stick with the 250 SWCs with the older smiths. A 250gr SWC @ 1100 will take of most your needs.

[BRobertson]

My 5 screw 4" 29 is .433 cyl 430 bore

4 screw 6.5" .433 430

629-4 .431 .430

Bob

[MtGun44]

Measuring one won't tell you much, except about that particular example. Like measuring feet - no
two the same except by accident.

If you imagine that all 29-2s will be the same or nearly the same - dream on.

Bill

[insanelupus]

Bill,

I'm just trying to get as many representative samples as possible. That is the point of the post. Between the folks who report back on here and the folks I talk to I'll have a decent idea of what to expect, though anomolies can always occur.

[Char-Gar]

Over the years I have slugged the bores and measured the cylinder throats of over one hundred Smith sixguns of various vintages. From pre-war to the mid-80 or thereabouts bores run .429 - .430 and the cylinder throats .432 - .434. Later ones had the same bore, but throats tightened to .431 plus or minus a half thou.

Cylinder gaps will depend on how much the pistol has been shot.

The older Smiths will turn in great accuracy with cast bullets .432 and of an alloy not harder than ACCWW. Avoid the commercial "hard cast" and water dropped bullets like the plague.

P.S... I don't want to mislead folks. Of the hundred or so Smiths I have measured about 25 have been 44s. Most have been 38/357 with a smattering of 45s thrown in. What I posted above is the results of what my records show.

[MtGun44]

Good luck, perhaps you will find a pattern. IME, they vary widely.

Bill

[bobthenailer]

I have a few S&W 44 mags, never measured the bores but i have measured cylinder throats with a pin guage. most shoot .430 dia cast bullets excellent the 2 that have what i call oversized cyl throats @ .432 & another @.433 I use .433 dia bullets in them with excellent results.

[Maximumbob54]

I haven't ever measured my 29-3 or 29-5 but they both shoot cast just fine. I don't push them to the max though. Using Unique loads I size them at .430" and lube them with an alox and JPW blend and don't get leading. But that same combo will lead my 629-6 like crazy. I cast from scrap lead and water drop them.

[Joni Lynn]

Most cylinder throats are going to be around .432" to .434" or there abouts. Starting with the 29-5 Magna Classic/Classic/Classic DX they were snugged up to about .4295" and the accuracy improved a bit.
Cylinder gap on the 29/629 guns I have or have had vary so greatly as to make giving an average spec pointless. S&W used to have (may still have) a max tolerance of .010" but I've had a few that were greater than that and one that was practically in multiples of that. Often the gap will be more on one side than the other. I think I was told the spec they aim for is .006" to .010"
When checking the gap remember to pull the cylinder to the rear first. This will let you know if it has end play and it will move rearward when fired because of that.