Sizing 0.001" OVER Cylinder Throat?

CZ93X62

CZ93X62

Official forum enigma
I have owned at least 15 38 Special and 357 Magnum revolvers over the years, and have likely fired 150K cast bullets through these arms over the past 45 years. both of these numbers estimates are quite conservative. EVERY ONE OF THOSE CASTINGS spec'ed @ .358" diameter. The only .357" bullets these guns have seen wore jackets, and there were at least 25K of those as well. I have yet to cause harm to any of these guns, though one of my Colt Trooper MK IIIs developed a loose extractor star.
 
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5shot

Active Member
CZ93X62 said:
EVERY ONE OF THOSE CASTINGS spec'ed @ .358" diameter. The only .357" bullets these guns have seen wore jackets, and there were at least 25K of those as well. I have yet to cause harm to any of these guns
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Was 0.358" oversized for the cylinder throats?
 
CZ93X62

CZ93X62

Official forum enigma
I have only had pin gauges for about 10 years or so, the 38/357 revolvers here now all run .357" to a few tenths larger. The gunmakers get the 38 Special and 357 Magnum throats CORRECT, IME. Same story with 41 Magnum throats, those are very reliably right at .410" to a few tenths larger. Other wheelgun calibers can be more of a crap-shoot.
 
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Inthebeech

New Member
You also may be sacrificing some precision by not sizing. Cast bullets can vary a bit out of the mold. Sizing ensures an exact diameter. Just something to keep in mind if you have OCD about precision like I unfortunately do.
 
JonB

JonB

Halcyon member
Inthebeech said:
You also may be sacrificing some precision by not sizing. Cast bullets can vary a bit out of the mold. Sizing ensures an exact diameter. Just something to keep in mind if you have OCD about precision like I unfortunately do.
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I was kinda thinking this same thing.

99.9% of my revolver shooting is 25 yds or less, and I suspect I wouldn't see any difference in accuracy by loading unsized bullets that may vary ±0.001" Dia. due to casting technique/mold temp variance.
BUT, I do suspect, a marksman shooting a revolver at 100 yds and beyond, could see some vertical stringing with bullets with that slight of size variance.
 
J

JustJim

Well-Known Member
L Ross said:
Welcome ITB. You are now among some of the OCDest, over thinking, pickers of nits ever digitally assembled in one place.
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I do not have OCD. I have CDO, with the letters in the correct order as they should be.

C'mon, I can't be the only one here who ever had the same mould in multiple diameters to see which shot best in a particular gun, or indexed bullets or cases in a chamber. . . .
 
Charles Graff

Charles Graff

Moderator Emeritus
Not much I can add, I will just say...

If you don't want to size the bullets then don't. I am not buying the cylinder slamming stuff.

Sizing the bullets .357 to fit your cylinder will most likely produce a smidge more accuracy, but most folks won 't notice it.

Das all!!
 
Bret4207

Bret4207

At the casting bench in the sky. RIP Bret.
When the primer lights the powder the pressure takes care of sizing. I may be a heathen, but I've shot a lot of unsized bullets that were in the .359 area and never have I had an issue in my Smiths or Colts. If they chamber, I try them. If I like the way they work, good. If I don't, I stop. It doesn't take 1,000 rounds to tell.
 
Charles Graff

Charles Graff

Moderator Emeritus
I have had and still do have quite a number of 38 Special revolvers made by both Colt and Smith and Wesson. I have also measured about 75 cylinder throats of such revolvers and have kept records and this is what I have learned. Please note there are a very few outliers but they do pop up from time to time.

Smith cylinder throats run .357 - .3572.
Colt cylinder throats run .358 - .359 with .359 being the most common.

I size my bullets .358 for both makes of revolvers. I have too many to fiddle with producing loads for individual revolvers and could not keep the ammo straight if I did. This works for me and produces all the accuracy I can use shooting the revolvers hand held.
 
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Petrol & Powder

Well-Known Member
My S&W and Ruger revolvers chambered in 38 Special generally have throats close to .357"
In the past I sized bullets for those guns to .358" but I have switched to .357" for all of my S&W/Ruger guns in that caliber. Bullets sized to .357" work much better in those guns and accuracy improved. So that's a no-brainer.
Like Charles, I just do not see the need to fiddle with producing loads for individual revolvers; nor could I keep them all straight if I did.
So, Charles and I are on the same page there.

Colts are a whole different ball game, but I don't play much in the Colt sandbox so that's a non-issue for me.

On another note, in my experience pistols chambered in 9mm Luger do not display the same consistency as S&W/Ruger 38 Special revolvers. In that arena I do find in necessary to load to a particular firearm. But that is also a whole different ball game.
 
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Petrol & Powder

Well-Known Member
This is going to be a bit blasphemous on this forum but here goes:
I can load jacketed 9mm Luger ammunition and get the resulting cartridge to work fairly well in a variety of pistols, but I've never had much luck in creating a "universal" 9mm Luger load with a cast bullet.
Perhaps if I powder coated but I'm too set in my ways to go down that path.

With a cast bullet in 9mm Luger, I pretty much have to load to a specific gun in order to get good results.
 
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