S & W Model 29-2 Cylinder Throat Size

[243winxb]

SAAMI lists a LEAD .432" bullet diameter & a barrel groove of .429" But there are tolerances listed. Comes down to, What works, works.

[Cosmic_Charlie]

My 24-3 has .432 "+ throats and does just fine with powder coated .431 boolits.

[zarrinvz24]

Thanks so much for all of your responses. I am absolutely amazed at the amount of information that you have freely shared. When I called S & W and gave them my Model 29’s serial number they told me that it was made in 1972. All of my measurements were taken with an inexpensive Chinese micrometer that I believe is accurate. When used to measure ten .430 Hornady XTP 240 grain bullets one was .4298, four were .4299, three were .4300, one was .4301 and one was .4302. Each Hornady was placed nose down on my bench for measurement as were my BHN 15 Lyman 429421 bullets. Within a few days I will measure some of my as cast Lyman’s, will try again to determine my throat size and will post the results.

You can get a nice Starrett or Mitutoyo Micrometer on the 'bay for a good price. I picked up a Starrett T230xfl-1 for $21 shipped last week. That's carbide anvils, friction thimble and USA made - doesn't get much better than that. While quality tools aren't cheap keep your eyes open for good deals. I try my best to operate under the "buy once, cry once" mentality; this has been reinforced over the years as I've been forced to upgrade to better tools - it would have been more cost effective to just buy the good stuff at the beginning. Good tools and equipment can make a dreaded task bearable. Just ask anyone that's got a Giraud case trimmer . . .

[44MAG#1]

Let me throw this out here. Since it is known reasonably well the early S&W 44 Mag's had large chamber throats why did Mr Elmer Keith recommend sizing bullets to .429 inch? He carried an early S&W 44 Mag 4 inch gun and took Flying Fish, Flying Birds, Coyotes at a quarter mile, Mule Deer at 250 yards with it.
Was he just lucky to hit anything with a bullet sized to .429 inch in large chamber throats since it is the rage now to size to chamber throat dimension?
Could it be possible that he was just lucky and not really that good since he didn't know he was doing it wrong?
What could he have done if he had done it right?

[Outpost75]

Keith used soft alloys which slugged up. He knew exactly what he was doing:

Sixgun Cartridges and Loads (1936) on pgs. 69-70 states:

“For most revolver cartridges, including all light and normal pressure loads, there is no use to having the bullets harder than one part tin to twenty parts lead for really heavy loads a one to fifteen mixture is hard enough… For automatic pistols, the bullets should be very hard, consisting of about one part tin to ten parts of lead, in order for them to slide up easily out of the magazine into the chamber… A mixture of part tin and part antimony works very well for some heavy loads, but such very hard, brittle bullets are not needed for any revolver load except in the case of extreme penetration, where no upsettage or expansion is wanted.”



I have found Keith's suggestions to work in my last 50 years experience following them.

[44MAG#1]

Are you assuming theyalways slugged up concentric and in perfect alignment with the center line of the bullet?

[44MAG#1]

While I am not very smart, I know some alloy slugs up more than others due to hardness when run at a given PSI.
Now can anyone give me evidence that each and every bullet cast from a given alloy sized a given amount, fired with a given load will slug up the EXACT same amount bullet fired after bullet fired?
Will the bullet shorten the exact same amount slugging up the same exact amount to prevent the COG from varying and that the driving bands slug up the same exact amount to keep the axis of the bullet that it rotates around after it leaves the barrel exactly the same as to prevent unnecessary yaw which would affect accuracy. Especially at long range.
If anyone can point me to a detailed study to answer my questions I would appreciate it.

[Petander]

My simple observations regarding mod 29, yes,often large throats.

I only have one at the moment, a 29-3 with .433-4335 throats. I slugged the barrel too but can't remember it any more,it was not large though... all I know I'm shooting the same .432" bullet that my 629 with reamed .432 throat likes.

That 4" 629 rings a 75 meter bullet trap with every shot. The good old 10" 29, maybe three times out of ten. No matter how fat a bullet I feed my 29, the barrel has the last word for a good size.

There's not much one can do with oversized throats and a standard bore. I just shoot my 29 and live with it, accuracy work is another thing altogether.

I have a -84 Redhawk with nice throat / groove ratio... I just wish it had a S&W trigger...



There is no limit for better accuracy. I almost quit all shooting ten years ago when I wasn't good enough, my 300 meter 1" BR groups were bad, my timed 0,5 sec pistol doubles were bad, nothing was ever good enough.

Just go shooting and enjoy your 29.

[mtgrs737]

I have measured several S&W 29's and a few 629"s and the blued 29's always seemed to have throats in the .433 - .434" diameter. The 629's were mostly undersized at .428" to .430" range. I suggested that if their owners wanted to shoot cast in them the 629's cylinders would need to be shipped to Doug Guy and have him open them up to .431" which he did and they shoot well now with cast which is what their owner was into. Leading was a problem with the tight throats. I have three pin gauge sets that cover diameters from .011" to .500" and are +.000" Minus .0001" and use them for precise measurements of throats. You can as someone here suggested just buy individual pin gauges in .428" thru .435" and you should have good coverage. In my experience stainless cylinders seem to run undersized when compared to blued steel cylinders probably due to higher wear of the stainless and companies trying to cut costs by re-sharpening reamers which can reduce their diameter. I recommend pin gauges and Doug Guy to fix your cylinders for you. A local machinist might measure your throats for you as a favor or for a six pack if you know any.