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Discussion Starter #1 (Edited)
Guys, what do you think of this Italian firearms manufacturer?

I had been looking for a while for 1892 leverguns with what I think are the proper twist rates for stabilizing heavy-for-caliber bullets in both the .44 magnum and .45 Colt: 1:20" for the .44, and 1:16" for the .45, to no avail.

Now, after researching a bit, I've come across this company, Chiappa Firearms.
They make their .44 mag and .45 Colt leverguns just like that.

Do you guys have any experience with them and what do you think of them?

Do they have the same strength as the Rossi 92's, that is, good for 50,000 psi?

http://chiappafirearms.com/product/817
 

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20170423_120822.jpg
Guys, what do you think of this Italian firearms manufacturer?

I had been looking for a while for 1892 leverguns with what I think are the proper twist rates for stabilizing heavy-for-caliber bullets in both the .44 magnum and .45 Colt: 1:20" for the .44, and 1:16" for the .45, to no avail.

Now, after researching a bit, I've come across this company, Chiappa Firearms.
They make their .44 mag and .45 Colt leverguns just like that.

Do you guys have any experience with them and what do you think of them?

Do they have the same strength as the Rossi 92's, that is, good for 50,000 psi?

http://chiappafirearms.com/product/817
In the event that anyone else is curious, I'll respond...

Yes, I own a Chiappa 1892 in 44 Magnum; it's a special version with a full length buttstock but a 12" barrel. That's completely legal here in Canada, without any restriction.

The quality of these guns is very high - fit and finish is good, materials excellent, no blemishes or tool marks, with one exception. The muzzle crown was rough, so I remedied that in ten minutes with a brass tool and valve grinding paste.

The ladder sight on the rifle is quite good, but my eyes are middle aged, and far from able to focus for best results, so I installed a Marbles tang peep from Brownells. Because the Chiappa is a clone of the Winchester 92, this sight is very easy to install. A tang peep on this short barrelled carbine increases the sight radius to the same as a 20" barrelled rifle with open sights. That is why I was willing to pay a premium for the Chiappa over the Rossi - the Italian gun is a faithful copy of the original, no stupid safeties or non-standard things like off-size sight dovetails. And, as you said, it has a fast 1:16 twist, which is why I preferred it over the Marlin 1894, which has a 1:38 barrel.

This little carbine is a hoot to shoot - it's just over 30" in length, and with a full magazine (six shots, not five as the specs say), it weighs just over five pounds. With full house loads (240 gr. Truncated Cone bullets and 24.0 gr. of W296), it's snappy, but not unpleasant to shoot, and it gets only about 100 fps less velocity than a 16" barrelled rifle. It's accurate, too...it'll group into about an inch @ 25 yards.

Photo is with the tang peep installed, but before the ladder rear was replaced with a dovetail filler.
 

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1-20 for 44mag and 1-16 for .45 colt. Oh really? In my opinion those rates are way to fast and need to be around 1-30. Which is what I'm told Rossi was using. Most everyone uses 1-16 for the Colt. The .44 mag hops around various twists from 1-20 1-30 to 1-38 depending on who is driving. Makes no sense to me. My Uberti .45 COlt is 1-16 with is too fast but deal with it by shooting them slower and using the heaviest bullet I can get.
 

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1-20 for 44mag and 1-16 for .45 colt. Oh really? In my opinion those rates are way to fast and need to be around 1-30. Which is what I'm told Rossi was using. Most everyone uses 1-16 for the Colt. The .44 mag hops around various twists from 1-20 1-30 to 1-38 depending on who is driving. Makes no sense to me. My Uberti .45 COlt is 1-16 with is too fast but deal with it by shooting them slower and using the heaviest bullet I can get.
Just curious, but what is it about the quicker twist that you don't like? Does it affect the bullet in some way that is detrimental to the bullet or accuracy? Seems to me being able to shoot a wider range of bullet weights would be advantageous. What is the down side? Like I said, just curious & not taking sides.
 

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Correct me if I'm wrong, but didn't the Marlin 1894 (44 Mag) change from a 1-38 Micro-Groove to a 1-20 Ballard type barrel around 1998 or so? I see post here sometimes, like shawnbo's, that only say the Marlin is a 1-38.
 

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I did considerable reading since yesterday when I posted that and I find that there are two strings of thought about twist rates. There is the "there is no such thing as overstabilization" group that claim that more is always better and the "too much twist will cause the bullet to fly like the space shuttle landing when it's drop's" which causes accuracy problems. After reading a bit it appears that the only effect over spinning has is that it amplifies the out of balance of the bullet at times and in only very severe cases. After believing that too fast a twist has negative effects on accuracy for a lifetime, trying to convince me it doesn't is like convincing me aliens are landing in my front yard and not to worry about it. I'm more confused than ever. Here's one article I read that explains the effect very well. Excuse me while I chase the aliens out of my front yard before the dog bites them.

https://anarchangel.blogspot.com/2007/01/stabilization-mythology.html
 

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The Hog Whisperer (Administrator)
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It really just depends on what you are doing. If you are deer hunting, and the bullets don't come apart leaving the muzzle; no big deal.

It IS a big deal if bullets are too fragile, and it CAN be a big deal when shooting some specialty, long range matches (eg. 1,000 yards and so forth).

But for most of us, no problem.....
 

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It's like we are to believe if the bullets aren't exploding when they leave the barrel we're OK. I find that hard to believe, Oh wait a minute one of the aliens is knocking at my door. I'll be back after I find out what he wants.........
 

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The 1:38 twist Marlin used on the 1894 works great for the typical 44 Mag loads of a 240 gr. bullet at rifle velocity (1700+ fps), otherwise they (and Browning in their 1892) wouldn't have used it. If you want to go with heavy bullets (300+ grs.), a faster twist is better. All the 44 Magnum handgun manufacturers use(d) 1:18 to 1:24 twist rates, because a 240 grain magnum load won't stabilize optimally at handgun velocities @ 1:38, and heavy bullets wouldn't stabilize at all.

Any given .429" bullet that is fine at 1:38 spin is NOT going to come apart at the same velocity in a 1:20 barrel, especially a bullet that doesn't have to negotiate a cylinder/barrel gap, at the velocity parameters of the 44 Magnum. If I'm shooting a 1892 repro with a 12" barrel, which I am, I want the faster twist.
 

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" If I'm shooting a 1892 repro with a 12" barrel, which I am, I want the faster twist."

Why would barrel length have any effect on what twist rate.?
 

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Chiappa is the parent company of Armi Sport, and Armi Sport makes great lever guns. Their Model 92 is a much more faithful copy of a Winchester Model 92, right down to the little details.

They are well made with great finish on both the metal and the wood, and they are however, in my experience, not quite as accurate as a Rossi 92 with cast bullet loads (see below for some discussion on that). But on the plus side, unlike a Rossi they are very slick functioning right out of the box and they are not over sprung like the Rossi Model 92.

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With regard to barrel twist, if you use a traditional twist rate formula and plug in a traditional .45 Colt lead bullet velocity of 1000 fps and a 255 gr cast bullet length of around .635", you get a ideal twist rate of about 1 in 36".

That seems slow, except the .45 caliber bullet has a large diameter and that large diameter brings with it more gyroscopic effect as the bullet spins, so it doesn't need (nor do you really want) as much spin.

Thus 1 in 36 to 1 in 38 rates made sense back in the day and they still make sense now with cast bullets in the 255 gr weight range at traditional non gas checked cast bullet velocities.

If you plug in a more modern bullet like the 250 gr FTX and a velocity of 1700 fps and it's longer bullet length of .660", you get an even slower ideal twist rate of about 1 in 44" due to the higher velocity.

If you go with a 300 gr FTX and punch it out at carbine velocities around 1500 fps, the extra length and reduced velocity puts the ideal twist rate at about 1 in 34" - where the traditional 1 in 30 something twist rates still work well.

However, if you use a 350 gr bullet with a length around .995" and push it at 1000 fps, the ideal twist rate now increases to about 1 in 22.

Thus, the faster twist rates in the 1 in 20 and 1 in 16 range makes sense, but only with long heavy 325-350 grain bullets at slow to moderate velocities. With everything else you're spinning the bullet faster than necessary. That's not a problem if the bullet is very high quality and the center of gravity and the center of form are both on the longitudinal axis of the bullet.

If they are not, (due to imperfect mold fill, an inclusion or void in the bullet, etc) the bullet will rotate around the center of form in the barrel, but will then have to transition to rotating around it's center of gravity once it leaves the barrel. This will result in yaw and the increased wind pressure on one side of the bullet will cause precession 90 degrees farter round the rotation. Excess spin will increase the precession, with adverse effects on accuracy.

That is why I suspect I get less accuracy with my Armi Sport Model 92 than with my Rossi 92s with cast bullets.
 

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1-20 for 44mag and 1-16 for .45 colt. Oh really? In my opinion those rates are way to fast and need to be around 1-30. Which is what I'm told Rossi was using. Most everyone uses 1-16 for the Colt. The .44 mag hops around various twists from 1-20 1-30 to 1-38 depending on who is driving. Makes no sense to me. My Uberti .45 COlt is 1-16 with is too fast but deal with it by shooting them slower and using the heaviest bullet I can get.
Utter nonsense. The 1-30" to 1-38" twists we're accustomed to are way too slow and folks have been clamoring for standard twist rates in leverguns for years. Those of us who hunt with these rifles and would like to shoot bullets +300gr have been left out unless we want to splurge for a custom rebarrel job. The handgun standard rates (1-16"/.45 or 1-20"/.44) works for all usable bullet weights and it's absurd to think they're too fast for anything.
 

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The Troll Whisperer (Moderator)
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Craig C -

Try to be a little more diplomatic in your responses. Thank you.
 

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While its possible to spin a bullet too slow it is also possible to spin it too fast. There is no such thing as "over stabilization" but spinning a cast bullet that has some imperfections causes the bullet to be unstable from being out of balance but not over stabilized. There is a difference. In a perfect world where bullets are perfectly balanced and round and perfectly centered in the bore when fired they will shoot just as good with a fast twist as with a slower twist. But the perfect world only exists in our minds. As you speed up the bullet you also risk stripping it past the initial rifling in the throat where it goes from 0 RPM to many thousands of RPM in a few milliseconds. I like to stabilise it enough but not so much I have to worry about stripping or wobbling. Winchester did many tests back when they created the 44-40 and determined that 1-38 was sufficient to stabilise the 200 grain lead bullet at 1300 or so FPS. I think that's too slow but upping that to 1-30 was a good compromise. I think they use 1-28 now in their japanese made 73's which is probably about perfect.
 

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The Hog Whisperer (Administrator)
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Twist rates are a funny thing. The first thing that people don't realize is, they aren't the exact same thing in every barrel coming off the line. Maybe hammer forged are? Button rifling can have 'fast' and 'slow' spots in the barrel.

I have 3 .25 cal barrels in different cartridges, and a 4th waiting on an action. Of the 3, one is exactly 1-10," one is 1-10.1" or so, and the other is closer to 1-10 3/8" Despite that, all three will shoot 120gr. bullets reasonably well. So it can be done.

I've known people who had .25 cal barrels that wouldn't shoot bullets over 100 grains well, but none of them measured the actual twist rate, before the gun or barrel went on down the road. So we really don't know if they were just a victim of the slower side of the manufacturing tolerance on the rifling, or it came off the line with the rifling machine set wrong.

My .444, with the s-l-o-w 1-38" twist, runs out of stability between 325 and 335grains, with the Beartooth 325gr. bullet. Initial groups were 'crappy' but on the paper at 100 yards. Closer inspection finally revealed that a few of the bullet holes were slightly oblong. Turning 0.050" off the nose of the bullet, tightened up groups dramatically.

On the other hand, Marshall shoots those same bullets in his Marlin .444, also with the slow twist rate, and doesn't have problems. I'd guess his "1-38" twist is a smidge faster than my "1-38" twist.

Point being, when you are at the edge of stability, it doesn't take much to cause problems.
 

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This ain't rocket science. There is no magic here. If it was too fast for the rifles, it would be too fast for the pistols. It ain't. Sure, the slower twists may be fine for bullets up to a certain weight but are closer to the edge of stability. Heavier bullets are over the edge and they tumble. If a 240gr is fine but a 300gr is teetering, you know you're way too close to the edge. The issue here has nothing to do with standard weight bullets in standard loads. Those work either way. The issue here is getting a fast enough twist to use the fullest potential of the cartridge with bullets up to 350-360gr. A 1-38" twist simply doesn't work for bullets much over 300gr unless you get into .444Marlin velocities. A 1-20" twist works for ALL bullet weights, proven fact.

What Winchester determined 140yrs ago with a lightweight 200gr bullet out of the .44-40 is irrelevant. What we need today is a fast twist barrel that will stabilize the same heavy bullets we use in our revolvers, which also works perfectly fine with lighter bullets. We finally have it, don't whine about it now.

EDIT: Using the Berger stability calculator, we see that a .430" 240gr at 1200fps in a 1-38" twist is marginally stable. Move up to a 300gr and you're even less stable, bordering on "unstable". That's fine for standard loads but anything much heavier is going to be unstable without more velocity.
 

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IMHO, once again, WAAAAAAAAAAAAAY too much is made of twist rate in big bores.


Very little of this article is relevant here. We're not talking about high velocity .22's where a few grains here and a couple inches of twist there make significant differences. Two or three inches of twist rate make a significant difference in the .223 but go completely unnoticed in a .44 or .45. Double the twist rate and you have something to talk about. Going from a 55gr to a 75gr bullet doesn't sound like much but in a .223, those 20grs are very significant. In a .44 or .45, in the context of stability, it ain't much at all. Context is important and everything is relative.
 
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