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Old August 25, 2012, 12:05 PM   #26
Pond, James Pond
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If you can find a load where bullet jump is not a problem with tying-up your cylinder and the accuracy has not deteriorated, then your bullet/powder combination seems workable. But, if your accuracy goes bad before your crimp is strong enough to stop the bullets from pulling out too far during recoil, then you need to work with a stronger bullet (jacketed or hard cast) or a powder that produces a less powerful load.
.44 cartridges costing what they do, I am not yet that experienced with my revolver (just under 300 dshots fired) and so, not that accurate either, but your point is noteworthy and so noted!!

However, I have a question.
It has been my understanding that one of the reasons to limit bullet creep is also to maintain your load's OAL. I had understood that an OAL beyond the manual maximum could cause pressure spikes and that this was one of the main reasons for getting a good crimp.

In terms of locking up the cylinder, my cartridges had best part of 5-7mm before the nose of the bullet would get anywhere near the mouth of the cylinder, but by then I'd have an OAL of 45.70-47.70mm!! By that stage, there would be barely any bullet still in the case!

So, I have been working toward a crimp choice using OAL as the guide, but pressure spikes as the concern behind it, rather than cylinder lock-up.

Do I, therefore, not need to worry about OAL other than for cylinder lock-up?
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Old August 25, 2012, 04:39 PM   #27
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The issue of pressure spikes due to OAL changes is primarily associated with auto-loading pistols, rather than revolvers. In auto-loaders, the OAL gets SHORTER when the bullet hits the feed ramp, unless the bullet is held tightly enough by the case. Auto-loaders typically use taper crimps because the case headspaces on its mouth, and a taper crimp is weaker than the roll crimp for holding a bullet in place. The shortened OAL leaes less room for the powder as it starts burning, and that raises pressure. Because there is so little powdr space to begin with in some of the small cartridges like the 9mm, the pressure increase can be substantial if the bullet sets-back even a mm.

In your revolver, the OAL getting SLIGHTLY longer is not a problem so long as it does not affect cylinder rotation. (That can be an issue with long bulets in short cylinders, but it seems like that isn't a problem for you.)

However, if your bullet is rather loose and pulls out of the case far enough to make one of the hard-to-ignite powders like H-110/WW-296 "squib" (burn just enough to get the bullet out of the case, but not out of the barrel), then firing another round with a bullet stuck in the barrel WILL create a pressure spike that could burst the barrel. The problem with "squib" loads is that they are not a sure thing one way or the other. One round may squib, but be followed by a round with the same powder charge that burns better and gets to high pressure. So, until you have checked the barrel for an obstruction, it is not safe to fire another round when one does not sound or feel "right" while shooting.

It would be helpful if you told us what powder, charge weight, primer and bullet weight you are using, so that we can focus on your particular situation instead of trying to describe a lot of things that may not apply to you.

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Old August 26, 2012, 02:56 AM   #28
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Thanks for the explanation. That's helped the penny drop: I understand more clearly now.

Quote:
It would be helpful if ....
Where I live I am limited in what I can afford and or get hold of. I say this as previously members have suggested changing this or that component, but for now I am stuck with what is below. Primers I can change to a degree, and powders too, but the latter are expensive, so if I change powders it will be when the existing lot is finished!!

All loaded with Lee press and dies and a Hornady digital scale.

Bullet:
H&N, copper-plated, high-speed, truncated cone, smooth sided (no cannelure), wax coated, .429", 200gr.

Case:
My S&B .44 mag cases that I got from buying factory loads.

Primer:
Either Remington or CCI Large Pistol Magnums, but have just bought some Fiocchi Large Pistol primers as that was all they had...

Powder:
Vihtavuori N350, 12.9gr (starting load)

As you can see from the first post, I forewent the taper crimp in the bullet seating die, using that only for the bullet OAL, but crimped instead with the Lee FCD. at .25 turn increments from no crimp to one full turn.

I've settled on 0.25 turn crimp as the increase in OAL is smallest between the first and fifth shot in a cylinder full, but even a full turn was not keeping the bullets still.

With this crimp bullet #6 in a clylinder should have stretched by .5mm by the time its turn down the barrel comes around.
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Old August 26, 2012, 10:06 AM   #29
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I am not familiar with the H&N plated bullets, so I can only use my experience with Ranier plated bullets.

I know that if you crimp the Raniers too hard, the plating gets cut and then some of it gets stripped in the bore and leads to minor leading but significant inaccuracy.

So, if you DO have inaccuray problems with your load, then you probably need to use a less powerful load with those bullets. Smaller charges of a faster burning powder would do that better than reducing your N350 load below "start" levels. If Vitavuori powder is what you can get, then N340 or N330 should be able to give you loads that work with a taper crimp. They would be about the power of .44 Special loads, not .44 Magnum "mid-range" loads.

But, if accuracy suits you and leading isn't a problem, then I don't see any reason to stop shooting what you already have. Just be aware that, if you increase your powder charge toward "max" your bullet pull-out due to recoil will increase.

In order to make handloads that reach the full power of the .44 Magnum, you will need to use bullets with crimp grooves (or cannelures) so that you can use a roll crimp. The powers that are used for full Magnum power loads typically need strong roll crimps to hold the bullet tightly enough to allow the powder to get properly ignited before the bullet starts moving forward.

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Old August 26, 2012, 10:32 AM   #30
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Thanks again for your input.

I don't plan to up my loads much. I will probably move to about 13.1gr and leave it at that. That is what the next disk cavity on my Lee Auto-disc measure seems to dispense. (in another thread I was having problems with getting the correct powder measure dispensed: it was below the starting load, but the next disc was more than I wanted.)

I will use up this powder, or at least wait until I have enough to buy a faster burning powder.

I can then use up all my existing supplies of bullets. Next time I may get cannelure grooved 240gr bullets from the same place, as well as a smaller supply of cast lead 300gr bullets from Midway Germany (€€€€!, but the cheaper H&N 300gr bullets are the same plated type and lack a cannelure groove).

Those I would load up to a medium-hot load (probably N110), find the best combination of crimp etc and then keep as a woods load. The 240gr loads would be for practice.

All this means that I wold have to buy another 2 or 3 powders (if I start reloading .308 too and they are about €80 per kg!! Not cheap, either....
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Old August 26, 2012, 12:29 PM   #31
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High[power loads with N110 and 300 grain bullets are probably going to be a challenge with respect to bullet pull-out if you don't have a crimp groove on the bullet.

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Old August 26, 2012, 01:16 PM   #32
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A challenge I do not desire!!

That is the main reason I'd go to Midway for the bullets, despite double the price, or more in some cases... They are all hard cast and have a groove.

Here are some...

... and some others...

... and yet others!
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Old August 26, 2012, 03:17 PM   #33
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As noted in the Berry's FAQ, those bullets are to be crimped using a slight taper crimp. A slight taper crimp is not really a crimp at all. It just removes the "flare" or "belling" from the expander die. Anything beyond that should be reserved for cast bullets with a crimp groove, or jacketed bullets with a cannelure.

The common term for the phenomenon you are trying to prevent is "bullet jump."

You can use those bullets in magnum revolvers with relatively light loads. Powerful but not near "full-house." If you are sizing and expanding correctly, you will have sufficient case mouth tension to prevent bullet jump. That's what's done with 9mm and .45acp pistols all the time.

The crimp in the picture is beyond brutal. It's bullet abuse.

Friendly recommendation #1: Stick with reloading measurements in inches. All American reloading data is built that way. Metric just confuses us.

Friendly recommendation #2: Row out into the Gulf of Finland about 100 yards. Take that Lee FCD and throw it as far as you can. Save yourself a lot of grief.
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Old August 26, 2012, 04:02 PM   #34
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Well, I certainly would not throw away a Lee FCD.

I do have some. But I don't use them for crimping. I use the carbide rings in the bodies for sizing my straight-walled pistol cases. Then I size just the part of the case that will grip the bullets with the regular carbide sized die, expand as usual, etc. That avoids the "wasp-waisted" look that you get when you try to size down toward the case head with the usual carbide sizer die. It also avoids working the brass so much in the lower part of the case, where it can split longitudinally from over-working. And, it leaves more room in the case for those slow-burning powders in those "business" loads that need to be hot.

Apparently, Redding thinks that is a good idea, because they recently came out with a 2-ring carbide die to do just that. And, they think it is such a good idea that we should be willing to pay $100 for their die!

And, if you really like the crimping part of the Lee FCD, but don't like that the carbide ring may post-size the case and bullet when using lead bullets, then just put the internals for the die for your catridge into the body of a die built for a cartridge with a larger body diameter, for instance, .44 internals in a .45 body. (The internals will fit/interchange with any Carbide FCD die body.) That way, you can get crimping wthout any possibility of post sizing. And, you have the actual caliber die body left over to do the initial sizing like I do. And, you get that for about $15 from Lee instead of $100 from Redding.

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Old August 27, 2012, 03:50 PM   #35
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Yes, it is a good idea. I've found by experimentation that coaxial alignment of a chambered round with the bore measurably reduces group size. Not so much with jacketed bullets, but with cast or softer plated bullets it matters. Keeping the back end of the case up to a maximum useful working diameter in any type of handgun helps with that alignment. In a revolver, in particular, if you both keep the base diameter up and use a bullet that's sized within a thousandth of an inch of the throat diameter and that is at least starting into the throat when you chamber it, that also improves the alignment. In a self-loader, seating out to start the bullet into the throat and headspace on the bullet further improves the alignment.

In the 1911 I've had that combination of loading steps cut group size by 40%. In a .38 Special K-frame revolver it cut 3" 25 yard groups to 1.5". I like the Lee Tumble Lube designs for this especially as you can use any of the little "microbands" as a crimp groove for revolvers and get the bullet seated right where it works best.
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