Slugged the bore. Check my fit.

C

Chainsaw.

New member
629 classic in 44mag. Bore comes out to .4295. My cast bullets are out of round at .4310-4325. Not expecting monumental accuracy are these bullet good to go? Or should I size for out of round?

Im thinking they'll be fine.... what say you guys?
 
How hard are your lead bullets ? If real hard it could be a problem .
If soft the bullet is still a little over size but will work . As for out of round the throats will fix that .
 
My cast bullets are out of round at .4310-4325
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If you do it right, and I am sure you will, you will measure the throats of the cylinder and size the bullets to fit.

Slug the cylinders or carefully measure with an accurate caliper.

Some guns are very accurate from cylinder to cylinder. One of my SBH has all cylinders dead on at 0.4311" and I size to 0.431"...a snug fit but constitutes very good accuracy.

I have another that had two cylinders that were small. I made them all a smidgen over 0.431" to match the others.

If you do this, then you will need to size and that will also correct the out of round bullets.

All of my revolvers have bullets match the throats. Once in a while you may run across one that the throats will be smaller than the barrel. Time to ream in that case.
 
If they'll chamber, they should do just fine. ...As long as the cylinder throats and forcing cone aren't smaller than the barrel's groove diameter.


Some guns are very accurate from cylinder to cylinder. One of my SBH has all cylinders dead on at 0.4311" and I size to 0.431"...a snug fit but constitutes very good accuracy.
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Yep. Some are good. Some, not so much.
And some can be both ... sort of.
My SBH ranged from 0.428" to 0.4315" throats, with a ~0.4295" groove diameter ("old method" cylinder), before I sent it back to Ruger.
I don't remember the exact dimensions and can't find my notes, but the new cylinder ("new method") has 6 throats within 0.0003" and they're all larger than groove diameter (0.4286" I believe). :D

But I still haven't checked for a forcing cone constriction. I'll probably get around to checking for a constriction on the SBH when I finally slug the S&W 29 and the .480 SRH. But the 29 shoots, and the .480 only sees gas checked lead which leaves a clean bore. So my priorities are elsewhere. One of these days...
 
Without very precise measuring tools, it's very difficult to determine exact bullet diameters, especially cast lead ones.
Calipers can't do that if, like most of us, that's what you are using.
 
How did you measure? Getting an accurate measurement on a S&W is difficult because it has an odd number of lands and grooves.
 
I don't slug the barrels on my revolvers...if the bullets have to be lightly pushed through the throats...I am good to go. All of my .44 revolvers shoot .430 like a champ.
 
I don't slug the barrels on my revolvers...if the bullets have to be lightly pushed through the throats...I am good to go. All of my .44 revolvers shoot .430 like a champ.
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Me either. I don't make much of an effort to solve a problem until I've confirmed that I've got one. I've been able to get good loads with standard sized cast bullets in everything pistol I shoot.
 
I'm one of those guys that needs to know what my guns' measurements are. "Push through", "drop through", etc. aren't measurements. Same with "about". I know the groove diameter for all my handguns and most of my rifles. I know the diameter of the cylinder throats on all my revolvers (I use pin gauges). I know the diameter of all my bullets, measured with a micrometer. For cast bullet shooting fit is more important than BHN. For new cast lead shooters I suggest sizing the same size as the cylinder throats for revolvers or .002" over groove diameter for semi-autos. This will give you a very good starting point to shooting lead free. It has worked for me in my 7 revolvers and 5 semi-autos that shoot cast bullets, and 3 rifles...
 
One of my SBH has all cylinders dead on at 0.4311"
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I don't know how you measure to .0001 tolerance on ID. Unless you are using a dial bore set to a XX or better ring guage or an air gauge using again a XX or better ring gauge then you are only guessing that is the ID. Calipers are only good for + or - .001.
 
I would not be concerned until I shot some and checked. If it does concern you then take the largest diameter bullet that you have and load it in an empty, primerless case. See if it will chamber in each hole. If it does then load them up and try them. If it fits in some holes but not others I would invest in a cheap push thru sizing die from Lee.

I'm guessing that you will be fine. Don't over think this.

I cast and load Lee tumble lube SWC as cast, without sizing and they are very accurate at moderate and magnum velocities. No leading.

If they are out of round in the cylinder a short trip down the barrel in front of 20,000 psi with take care of it.

After firing you can see if there is leading at the throat or in the barrel. My guess is you won't have any. I believe in shooting first and then finding problems later.
 
Thats pretty much what Ive come to given my readings here amd else were. Thanks for the advise. All I've loaded have chambered just dandy and Im only getting slight leading about the last inch of barrel with powder coating.
 
If the leading that you are seeing comes out easily with a bore brush then you are good to go.

Also, it could be "antimonial wash" instead of leading, that is, it could be trace deposits of antimony that come clean easily. Again, don't worry.

A snug fitting bore patch on a jag will tell you. If you push a tight patch through and the bore cleans up it is metal wash or soot. You can "read" the patch for clues.

You sound like you are doing it right. Keep reading and experimenting and learning.
 
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