Chamfering on throat end of cylinder?

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OlongJohnson

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I've seen a couple S&Ws on a popular auction site lately that appeared to have had the charge holes chamfered on the throat end of the cylinder. All the revolvers I have available to inspect range from reasonably crisp and square at those hole edges to slightly broken/polished edges, really just enough to not be sharp. As I understand it, that's how it's supposed to be.

I've seen someone on the web admit to screwing up and chamfering the throat end of the charge holes when attempting a DIY chamfer, clearly without understanding the purpose of what they were attempting to do - just something that cool kids do, so do it to your own gun.

I've seen some really screwed up stuff come out of the S&W factory both the first time and as a result of customer service gone wrong, but never personally this particular screw up. The first one I saw that stood out was a 627-5 non-PC gun a week or two ago. Posted a link on another forum where I'm more active, and someone said it was a factory gun. Chamfers were wide and really badly chattery. It's hard for me to believe that was done at the factory. Today, I'm looking at a 60-18, the one with a five-inch barrel. Focus isn't super crisp, but there's clearly a noticeable either rounded or chamfered edge that's nice and shiny at the edge of the charge holes on the throat end.

So I'm posting here to see if this is something I don't know about. I'm always a fan of learning, especially if it doesn't cost me money. Is chamfering to a greater or lesser extent on the throat end of the charge holes something that varies or comes and goes in S&W production? Is there any functional reason you'd want that edge to be broken beyond "not sharp?" Or is it the "Bubba tracks" that I'm currently assuming it to be.
 
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I've seen some chamfering on PC guns the past few years that seemed excessive. I'm surpised the extractors actually work on these guns considering the amount of material that has been removed.
There's actually a video or two of the Performance Center that shows this being done. So the purpose is to help facilitate loading??

Here's an example I found on the web.....a Performance Center model 627

 
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I'm a little confused. What exactly do you mean by "throat end"? When I read that, it makes me think of the front of the cylinder, by the barrel throat. If that's the case, I've never seen or heard of that being done.

If you're talking about the rear of the cylinder, like in the photo armorer951 posted, then chamfering the charge holes is a common practice meant to make reloading easier/smoother, so bullets don't hang up on the edge. For that, it should be very slight, maybe just breaking the edge, and often just on the cylinder itself as chamfering the extractor star can cause issues with extraction. As far as I know, they're not a standard part of manufacturing, maybe done on special editions or maybe Performance Center guns. None of the S&W revolvers I've bought came that way from the factory, but I've only bought a few and none were limited edition or special models.

Sorry again for my confusion.

Edit: Disregard my confusion. I think I get it now. I probably shouldn't post before I've had breakfast. :o
 
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I have a 625-4 that shoots .45 ACP with moon clips or .45 AR. I use .45 ACP and loading can be a bit slow, because the case mouths tend to catch on the cylinder. I don’t compete with it and speed isn’t an issue, so I just wiggle the loaded clips and they eventually drop in.

I’ve considered having the charge holes chamfered, but haven’t bothered t do it yet. I prefer to keep guns stock, but I’m sure it would improve the performance in this case. The modification, especially when shooting automatic pistol cartridges that seat on the case mouth, is not without merit.
 
In the picture of the PC 627 you will see the cylinder chamfered as it comes from the factory. A close examination of the extractor will reveal that the chamfering is done selectively only in the middle of each chamber, then tapering off at the sides. The rim of the case is pulled out of the chamber like 2 fingers, 180 degrees apart. If the chamfer went all the way around the extractor fingers, the extractor would only pull out rounds in a moonclip, not individual loose rounds.

As far as chamfering the holes in the front of the cylinder, that is a bad idea. All that does is encourage a lot more gas and pressure to escape out the cylinder gap when firing. The best case is a crisp square edge with no burrs.
 
s&wchad said:
I have a 625-4 that shoots .45 ACP with moon clips or .45 AR. I use .45 ACP and loading can be a bit slow, because the case mouths tend to catch on the cylinder. I don’t compete with it and speed isn’t an issue, so I just wiggle the loaded clips and they eventually drop in.

I’ve considered having the charge holes chamfered, but haven’t bothered t do it yet. I prefer to keep guns stock, but I’m sure it would improve the performance in this case. The modification, especially when shooting automatic pistol cartridges that seat on the case mouth, is not without merit.
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I have a 625-3 that I had the charge holes chamfered . The chamfering is very slight, just enough to break the sharp edge of the hole . You have to look good to see it but it made a huge difference in the loading speed and ease . They don’t have to be funnels to work good .
 
I just checked two of my Ruger LCR‘s; one in .327 and one in .22M. They are both slightly chamfered on the throat end of the cylinder. My bedside 637 is also chamfered. It’s a little harder to see, but can be seen plainly if I shine a flashlight on the cylinder face. Just to match the other posts here, I will put in a picture of the ratchet end of the cylinder tomorrow ... ;)
 
#1 If the cyl holes have throats they're chambers, not charge holes. Charge hole is a cap and ball era term because there's no shoulder in the hole. Albeit charge holes did carry over into the early cartridge era for cartridges using heeled bullets (like .22s) because heeled bullets have the same diameter as the case. Therefore only today's .22 chambered revolvers still use charge holes.

#2 There's no benefit and potential downsides to chamfering the chambers at the front face of the cyl except a slight breaking of the sharp edges.

#3 Chamfering the mouths of the chambers at the rear face of the cyl is mainly for ease of using speed loaders. And yes current chamfering often is deeper on the extractor because that's where bullets in speed loaders tend to hang up; towards the center of the cyl more than anywhere else on the chamber mouths. The extractor star still works as designed because the chamfer is tapered on an angle.

For individually loaded rounds, an even chamfer around the chamber mouth is sufficient.
 
A little chamfer at the breech end of each chamber goes a long way toward making a speed loader and full wadcutters align more quickly. I managed a service revolver (Model 66 ND) with no chamfer quite well using LSWCs and Safariland Jet Loaders well though.

Froggie
 
When I was a serious PPC shooter in the 70s and early 80s I chamfered both my Model 28 6'' and my "Off Duty Class" 15 2'' for a easier quicker reload.

I was shooting semi wadcutter .38 and to me it helped out my big hands a lot. (way too many problems using full wad cutter loads)

I did the chamfering myself as I'm well used to working with metal and metal removal and polishing/honing tools. (go slow its faster:D)
 
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