Smith and Wesson 44 mag Cylinder Throat measurements

[Tikkakoski]

Hey Guys,

I just recently picked up a 629 performance center vcomp in 44 mag. The action is incredibly smooth and its a joy to shoot. I picked up some hard cast lead bullets in 200 and 240 grain and they were both swaged to .430 from the manufacturer. I have loaded both of these to velocities ranging from 44 special pressures up to high 44 mag pressures and no matter what powder I use, I get an outstanding amount of leading. I recovered one of the 240 grain bullets shot into soft dirt and it measures out anywhere from .417-.424. I decided to measure my cylinder throats and they are all right at .424-.4245. That seems way to restrictive to be shoving a .430 diameter bullet through. Im curious if any of you 44 mag owners out there would mind measuring your cylinder throats and seeing what you measure out at. Im thinking this could be causing a ton of gas cutting that is making my barrel lead up like crazy. I called smith to ask them what the measurements should be and they said they didnt have that info and just offered to have me send it in.

Thanks for the help guys I'm scratching my head over this one lol.

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[osprey]

That seems tight for the throats. What did you measure them with. Maybe take a unloaded bullet and mic it to get diameter and put it in each hole. A .430" sized bullet should have to be forced through pretty hard if they are really .424 throats. Usually with cast you want bullets sized .001 or so larger than bore and throats should accomodate that size with only a minor push needed to go through throats.

 

[Tikkakoski]

That seems tight for the throats. What did you measure them with. Maybe take a unloaded bullet and mic it to get diameter and put it in each hole. A .430" sized bullet should have to be forced through pretty hard if they are really .424 throats. Usually with cast you want bullets sized .001 or so larger than bore and throats should accomodate that size with only a minor push needed to go through throats.

I used a set of dial calipers to measure everything. The .430 sized unshot bullet wont even fit into the barrel side of the cylinder past the bevel on the base. The shot bullet still has to be pushed through with moderate pressure.

 

[osprey]

Almost impossible to measure throats accurately with calipers. Take it to a smith and have him check it out. It sounds like they may be a bit tight. Also barrel needs to be slugged to determine proper bullet size to use and then throats adjusted to accommodate that bullet size.

 

[Certaindeaf]

.they were both swaged to .430 from the manufacturer.

You keep saying essentially that two times but did you measure them with a micrometer or just read the side of the box? And pull one before firing it and measure it (don't dig it out of the dirt) to see if your reloading methodology changes the bullet diameter before even firing.

 

[po18guy]

Outside measurement is fine with calipers. For inside, you need a ball gauge or inside mic. Do you have any jacketed bullets (.4295) to check the throats with?

 

[Ura-Ki]

I would measure the cylinder with SNAP gauges, essentially "Ball" Gauges to get the most accurate and consistent readings, and also measure the throat just past the forcing cone.

 

[Tikkakoski]

You keep saying essentially that two times but did you measure them with a micrometer or just read the side of the box? And pull one before firing it and measure it (don't dig it out of the dirt) to see if your reloading methodology changes the bullet diameter before even firing.

Im not sure what you mean by saying .430 two times. All measurements Ive posted were taken with a dial Micrometer. But yes, the bullet manufacturer diameter matches what I measure here at the bench. The bullet I was able to recover is in impecable shape and shows no deformation. The rifling grooves are crisp and clear.

 

[Tikkakoski]

I would measure the cylinder with SNAP gauges, essentially "Ball" Gauges to get the most accurate and consistent readings, and also measure the throat just past the forcing cone.
View attachment 505635

I was worried about that. Where is a good place to pic up a set of ball gauges?

 

[Tikkakoski]

Outside measurement is fine with calipers. For inside, you need a ball gauge or inside mic. Do you have any jacketed bullets (.4295) to check the throats with?

I do have some nosler JHPs. They should be be able to be pushed through the cylinder with moderate resistance right?

 

[Tikkakoski]

Outside measurement is fine with calipers. For inside, you need a ball gauge or inside mic. Do you have any jacketed bullets (.4295) to check the throats with?

Just checked some nosler jhps that mic out at .4285 and with decent pressure I was able to push them through the cylinder with a wooden dowel by hand.

 

[Ura-Ki]

I was worried about that. Where is a good place to pic up a set of ball gauges?

I got mine off the tool truck ( Cornwell) and they were less then $40 for the set, and I use the hell out of them too! well worth having if you have other projects to play with!

 

[KKG]

If it was in my shop I'd check the Forcing Cone and see if it's right. Then I'd take a look at how rough the Bore is. Recently I had a customer bring in a 686 that didn't have Any Forcing Cone. Lots of things need to be checked out on the guns coming from S&W these days.

 

[Ura-Ki]

Especially something coming out of the performance center, things tend to be a little too tight from them, so I would definitely give it a close look!
I had my brother complain about his Performance center 1911, one look told me all I needed to know, and 4 hours later with the 1911 tools had it running like a Swiss Watch

 

[po18guy]

You may also need to slug the bore. Do you have another .44 to shoot those bullets though for comparison?

 

[Tikkakoski]

I got mine off the tool truck ( Cornwell) and they were less then $40 for the set, and I use the hell out of them too! well worth having if you have other projects to play with!

Sounds like a set of ball gauges is in my future before i get too far ahead of myself.

If it was in my shop I'd check the Forcing Cone and see if it's right. Then I'd take a look at how rough the Bore is. Recently I had a customer bring in a 686 that didn't have Any Forcing Cone. Lots of things need to be checked out on the guns coming from S&W these days.

Short of slugging my barrel what else can I visually check on the forcing cone? Anything specific to look for?

Especially something coming out of the performance center, things tend to be a little too tight from them, so I would definitely give it a close look!
I had my brother complain about his Performance center 1911, one look told me all I needed to know, and 4 hours later with the 1911 tools had it running like a Swiss Watch

Im hoping im doing something stupid. The fit and finish of the rest of the gun really is superb.

You may also need to slug the bore. Do you have another .44 to shoot those bullets though for comparison?

A bore slugging is probably in my future. Of course I just sold my ruger SBH 44 lol...

 

[KKG]

...Short of slugging my barrel what else can I visually check on the forcing cone? Anything specific to look for?...

My suggestion is that you need to find yourself a good Pistolsmith who has a set of Forcing Cone Gauges and maybe a Bore Scope and maybe several other sets of gauges and have him check your pistol out. Since you didn"t provide your location I can't make any suggestions as to who you might want to take it to.

 

[Tikkakoski]

My suggestion is that you need to find yourself a good Pistolsmith who has a set of Forcing Cone Gauges and maybe a Bore Scope and maybe several other sets of gauges and have him check your pistol out. Since you didn"t provide your location I can't make any suggestions as to who you might want to take it to.

Im in Hillsboro OR just west of PDX.

 

[CLT65]

Just checked some nosler jhps that mic out at .4285 and with decent pressure I was able to push them through the cylinder with a wooden dowel by hand.

If you can push a .4285" jacketed bullet through the cylinder throats at all, it's safe to say they're bigger than .425", probably more like .428+". That's still way too tight in my opinion. For lead you want at least bore diameter. My Model 29s are at least .430". I shoot lead exclusively (powder coated), often loaded to maximum, with no leading.

Is it a new gun that S&W will warranty? Might ask them what their spec is. It would stink to send it in, only to have them say it was "in spec" and just send it back without fixing it. I've seen that sort of thing happen.

There's a guy on another forum who specializes in exactly this sort of thing. He has an excellent reputation and his prices are very reasonable; you mail the cylinder to him and he sends it back with the throats reamed perfectly for the bullets you want to shoot. Let me know if that's something you're interested in and I'll look for his info and send it to you.

 

[Tikkakoski]

If you can push a .4285" jacketed bullet through the cylinder throats at all, it's safe to say they're bigger than .425", probably more like .428+". That's still way too tight in my opinion. For lead you want at least bore diameter. My Model 29s are at least .430". I shoot lead exclusively (powder coated), often loaded to maximum, with no leading.

Is it a new gun that S&W will warranty? Might ask them what their spec is. It would stink to send it in, only to have them say it was "in spec" and just send it back without fixing it. I've seen that sort of thing happen.

There's a guy on another forum who specializes in exactly this sort of thing. He has an excellent reputation and his prices are very reasonable; you mail the cylinder to him and he sends it back with the throats reamed perfectly for the bullets you want to shoot. Let me know if that's something you're interested in and I'll look for his info and send it to you.

The revolver is brand new and definitely under warranty. I called smith today and asked them what they dream the cylinders too and they weren't able to find that info but offered to let me send it in no questions asked. But like you said, 4-8 weeks and nothing may be wrong with it according to their gunsmiths. The weird thing is it seems to shoot lead pretty accurate I'm just fighting terrible leading. If it's not too much trouble to find that info that's definitely something I'd like to look into. Im thinking I really need to slug my cylinder and bore.