Hone GP100's cylinder mouth?

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coolluke01

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My GP100 is a little sticky when using speed loaders. The shells require a little jiggling to get the rounds to go in.

Has anyone honed the cylinder mouth (for lack of proper term)?

If there is a tool to do this I would feel confident doing it my self. But I would shy away from any hand tool options.
 
I would trust the machining specs of the gun before the plastic speed loader made in China. Try another brand of loader or just a different one of the same kind. Doubt its the guns fault. Could also be the ammo.
 
You can have the chambers chamfered by a gunsmith (or do it yourself if you feel you have adequate skill) to help with quickly reloading. It is a process of cutting an angle into the mouths of the chamber ends so it's not a 90* degree angle from face of the cylinder to chambers. It's also known as crowning when it's done to the end of a barrel.

Or as a cheaper and possibly safer alternative, you could try a different speed loader.
 
It is usually called chamfering, and MUST be done with the extractor "star" removed from the cylinder. If your speedloader is binding against the grip, don't blame the chamber mouths, do something about the grip, or use different speedloaders.
 
What speedloader are you using?

I use a Safariland and an HKS in my GP100 with no problems
 
Bullet profiles , yellow brass/nickeled brass will affect the feeding but not as much as the actual length of the case , the longer the case the more wiggle/jiggle the free end has .

I also use HKS & with SWC ammo my reload time is .5 sec. longer averaging 10 reloads. The shoulders catch everytime.

PS : some custom smithing companys offer reaming the throats to all the same size & chamfering with out sending the whole gun so ya can do it thru the mail ! & the end of the cyl your talkin `bout is the mouths of the chamber end.
 
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Could also be the grip(s). Not enough clearance can prevent quick dropping of the rounds. For instance, the stock grip on the SP101 is a problem in this regard, but the Hogue replacement isn't. I know that for a fact.
 
The grips aren't in the way. The speed loaders clear the grips with no problem.
I use HKS speed loaders .

I was just at a revolver match tonight. It took some jiggling for the rounds to go in. I talked to a few guys there and some of them have had a local gunsmith chamfer the mouths and one did it himself.

I used new brass cased FMJ round nose this time. I had used some cheap aluminum cased stuff with lead that had a ledge right at the top of the case. It was a real pain. I figured the ammo with the brass cases and the FMJ would be better, they were but still needed a little jiggling.

Someone else used my gun with Safariland speed loaders and they had to jiggle it a little bit too.

If I were to take a lager cone dermal bit and ran it just a touch on the mouth, would that give me the chamfer I'm looking for? I figure I just need to knock the edge off a tiny bit.

That's an interesting point made about taking the extractor out. Is that recommended? Would it really be a problem to take the edge of that? I see that the extractor is set back outside the cylinder just a touch.
 
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and MUST be done with the extractor "star" removed from the cylinder.
That sure NEWS to me.
I've done too many to count and always do it with the extractor star in place.

If the extractor star has a sharp edge on it, it needs to be chamfered along with the rest of the chamber mouth.

And if you take the extractor out, a typical chamfering tool will not cut evenly all the way around with part of the chamber mouth missing!!!

http://www.midwayusa.com/product/821348/ptg-revolver-deburring-tool-1-2

rc
 
A very good gun smith can chamfer the cylinder, but as already stated, leave that to a qualified smith. If you try doing this yourself and get it wrong you have ruined your cylinder, or worse.

I have a 66-2 that was chamfered by S&W, and it does make a big difference when using a speed loader.

GS
 
Let ya local smith do the chamfering , coins well spent in my book.

& yes it`s done with the extractor in place , I mean agreed extractor needs chamfering also .
 
Do not try to do a chamfering job with a dremel. You'll regret it. I use Safariland speedloaders with my GP100 and they seem to work fine, but I'm not up against a clock on my reloads.
 
I've done this with a simple countersink bit available from any hardware store.

I prefer to just ease the edges (yeah, I do the star too) and not go overboard.

If you can find a bit-holder you can turn by hand, you can do the job without power tools, but it will take quite a while.

I lock the cylinder into a vice and chuck the countersink bit into a cordless drill and run it as slowly as possible, stopping every few turns to check my progress. About the time I can see a sliver of chamfered edge, I'm done!

That's enough to keep the sharp edges from biting the brass and hanging up the cases going in.

If you want them wallowed out like Jerry Miculek's 625s -- take it to a 'smith!
 
What's the down side of wallowing them out? Unsupported chamber? I'm really looking for speed and ease of loading. I know more is not always better but how far can you go before you start causing issues?
 
Really wallowing them out means you only get one firing out of your brass because it will bulge in the unsupported areas.

How far can you go? I don't know, but a shop who specializes in revolvers (maybe C&S?) could probably advise you on that.

That's a more complicated question, and job, than a little chamfering.
 
What's the down side of wallowing them out? Unsupported chamber?
Not like you would think of an unsupported chamber in an auto pistol.

I don't have a sectioned revolver case photo, but they are very similiar to these.
Note the solid brass case head is just that.
Solid.

Caseweb.jpg

SO, as long as you don't chamfer deeper then where the thin case web starts, they won't expand into the chamfer.

And there is no need to ever go that deep.

All you have to do is break the sharp 90 degree edges and polish them, and the rounds in a speed-loader will fall in like corn through a goose.

rc
 
coolluke01 said:
What's the down side of wallowing them out? Unsupported chamber? I'm really looking for speed and ease of loading.

You don't need hogged out chamber mouths for fast reloads.

Beyond a moderate chamfer, the secret to speedy reloads is 1) ditch the HKS loaders and use push-release loaders (fastest are "Bubber-ized" CompIIIs or JetLoaders), 2) proper technique (some good instruction goes a long way here), 3) round nose bullets and 4) a metric ton of practice with dummy rounds at home. You can make funnels out of the charge holes, but unless you apply these "secrets" (especially #4), it won't matter much.

Keep in mind that your reload is only as good as your shots right before and after. A speedy reload in and of itself is worthless if your shot before and after the reload are bad because you rushed them off.
 
I was trying to figure out the fastest way to reload the other night. I tried everything I could think of and settled on strong hand reload and hitting the ejector with my thumb.

I just searched youtube to see if you had made a speed loading demo video MrBorland. I found one and sure enough I picked the same way you had demonstrated.
It's going to take a ton of practice but I think it's a good method.

Do you prefer the Jetloaders over the Safari land? I also looked up this Bubber-ised comp III's. That's an interesting process. Would this be helpful to do on the jet loaders too? Or don't they need it?
 
coolluke01 said:
I was trying to figure out the fastest way to reload the other night. I tried everything I could think of and settled on strong hand reload and hitting the ejector with my thumb.

When using speedloaders, I primarily use a strong hand reload, but it's mainly weakhand reloads with my moonclipped 625 .45acp. It's good to eventually be proficient with both methods, as there are times when the course of fire may make one faster (or safer) than the other.

I do use my thumb, but others hit the ejector with their strong hand before reaching for the speedloader. If you use your thumb, you can get to your speedloader quicker, but you risk having brass hang up if your thumb stroke is weak. It's best, then, if you practice reloads with empty brass in the gun (unlike my bad example in my reloading vid :eek:). Even better is using dirty non-resized brass to emulate what you'll actually be ejecting during live fire.

coolluke01 said:
Do you prefer the Jetloaders over the Safari land? I also looked up this Bubber-ised comp III's. That's an interesting process. Would this be helpful to do on the jet loaders too? Or don't they need it?

My personal preference is for JetLoaders. The diameter of the body is a teensy bit smaller than CompIIIs, so it gives one a teensy bit more room during the reload. After seeing it a few times, I'm also concerned about crud accumulating behind the CompIIIs spring shroud and making their release finicky. I think I'd just cut that shroud off if I were using CompIIIs.

JetLoaders benefit from Bubberizing, too. The idea is to cut down the body of the loader so the injected rounds clear the speedloader easier. Be sure to avoid cutting the center plunger, and do get rid of all plastic burrs after cutting. I cut about half the body off mine, and they work well. I've seen some that were radically cut down, but at some point you'll need a loading block to load the speedloaders.

One other mod to speedloaders I can recommend is to fill the hole (I use JB weld) in the center plunger if one is there (my k-frame Jetloader plungers don't have a hole). I'm not sure why the hole's there in the first place, but it'll catch on the inner ejector rod, making it tough for the speedloader to fall free.


JetLoader2.jpg
 
Man, they already call me "Gamer" as it is at the range. Imagine if I show up with chopped down speed loaders and funnels for cylinder mouths. ;)

It looks like the Comp III's are a lot of work to take apart and trim down. Are there any tricks to that? Are the Jet loaders easier?
 
coolluke01 said:
Man, they already call me "Gamer" as it is at the range.

While using HKS loaders and unchamfered cylinders at a revolver match? :eek: A little sensitive, aren't they? You might remind them it is a game, after all. :rolleyes:

coolluke01 said:
It looks like the Comp III's are a lot of work to take apart and trim down. Are there any tricks to that? Are the Jet loaders easier?

No disassembly required, so both ought to be similarly easy. I use a bandsaw, but a Dremel & a cutting wheel ought to work well, too. Just be sure to get rid of all the little plastic burrs when done. Test each position on the speedloader with an empty case - you shouldn't feel any resistance when it enters or leaves the loader.
 
That sure NEWS to me.
I've done too many to count and always do it with the extractor star in place.

If the extractor star has a sharp edge on it, it needs to be chamfered along with the rest of the chamber mouth.

And if you take the extractor out, a typical chamfering tool will not cut evenly all the way around with part of the chamber mouth missing!!!

http://www.midwayusa.com/product/821348/ptg-revolver-deburring-tool-1-2

rc

Chamfering the extractor can reduce its its ability to grab the cartridge, to toss it clear, and may let it over-ride the cartridge rim. I would think a tool made for chamfering DA revolvers should have a pilot that keeps it aligned with the chamber, so it would work without the extractor in place. The chamfering tool I had considered buying from Brownell's had such a feature.
 
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.38's and .44's have plenty of rim to push on, so a light chamfer/polish on the extractor is fine. I would be wary of trying it with a .45 Colt though, where the rims are tiny. No one is using them for revolver games though.
 
Something else to watch out for is to not use a semi-wadcutter-profiled bullet (on far left). A popular .38 Special defense load uses this type with a hollow cavity. The shoulder will catch on the chamber mouth.

image010-1.jpg


You want a rounded-profile bullet like the hollowpoint (third from left).
 
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