Henry rimfire rifling & twist rate

[henry22]

Hello guys. I just read this really interesting article on rifling and twist rates. https://www.ballisticmag.com/2015/05/01 ... te-basics/

I recently found out that the Henry H001 series rifles have a 1:16 twist rate. Based on the CZ 455 .17 HMR with a twist rate of 1:9, can we assume that the Henry H001V with it's 20" barrel also has a 1:9 twist?

Would there be any benefit for a 22LR or 22 WMR to have a higher twist ratio, like 1:9, or 1:16?

Are there any manufacturers who produce 22 rimfire rifles with a twist ratio other than 1:16?

Just curious - thanks.

[markiver54]

Good question, I would also like to know how and why Henry arrived at their twist rate.

[PT7]

Hello guys.
I recently found out that the Henry H001 series rifles have a 1:16 twist rate. Based on the CZ 455 .17 HMR with a twist rate of 1:9, can we assume that the Henry H001V with it's 20" barrel also has a 1:9 twist?

Listed on Henry site under the H001V specs https://www.henryusa.com/rifles/varmint ... hmr-rifle/ are the following:

Varmint Express .17 HMR (H001V)
Barrel Length: 19.25"
Barrel Type: Round Blued Steel
Rate of Twist: 1:9

[North Country Gal]

The twist rate for a given cartridge is based on the caliber (bore size), velocity, bullet weight (actually bullet length) and bullet style. In a cartridge like the 223, with a wide variety of bullet weights (again, bullet lengths, but easier to discuss in terms of bullet weight), you do need to choose which twist you want for your barrel, since you have so many choices in terms of bullet weights/lengths. There was a time when shooting a 223 meant shooting either a 50 or 55 grain bullet, but no more. Now you can go anywhere from a 40 grainer up to an 80 grainer. Most articles on the net about twist rate are based on discussions of the 223, for this very reason.

On the 22 LR, though, the twist rate has been standardized for generations, now, at 1-16, because that's the optimism twist for the usual 37-40 grain bullets at the usual velocities used in a 22 LR. That's not going to change, simply because the 22 LR is pretty much stuck using those 37-40 grain bullet weight/lengths.

This isn't so much as restriction of the cartridge, itself. It's a matter of the guns that shoot the 22 LR. The overall cartridge length of the 22 LR needs to be tightly controlled in order for 22 LR ammo to feed in the millions of 22 LR rifles and pistols in use, some now over 100 years old. Even the slightest deviation in cartridge length on the 22 LR can cause feeding issues in some guns, so the typical bullet weights will always be restricted to that 37 to 40 grains, though some ammo manufacturers have tried to get around this with hyper velocity 22 LR loads that offer lighter bullets, but in longer than standard 22 LR cases to maintain that overall 22 LR cartridge length. Even then, some 22 LR guns can be extraordinarily fussy about cartridge length and refuse to feed with Brand Xs 40 grain load, but do just fine with Brand Ys 40 grain load. Then, too, some guns will absolutely not feed the hyper velocity stuff at all and manufacturers will warn you in the manual not to use it in particular models.

Yes, you could change the twist on a 22 LR to, say, a faster 1 in 10. All that would do, though, is create more lead fouling.

As for the 17 HMR, the only thing it has in common with the 22 LR is that it is a rimfire. It's a vastly different cartridge in terms of bore size, bullet weights/lengths, velocity and, therefore, twist rate needed.

[henry22]

Haha, NCG, I just posted in the middle of what you posted, otherwise I wouldn't have posted this.

Me too Mark. But I've recently just found out that most 22LR rifles have a 1:16 ratio. It's just the nature of that cartridge, bullet diameter, length, and the FPS that a given cartridge can provide.

Example:

22LR CARTRIDGE
Bullet length: .224
Bullet diameter: 0.223

MUZZLE VELOCITY - NOMINAL
40-grain (2.6 g) lead: 1,082 ft/s (330 m/s) .22 LR subsonic
36-grain (2.3 g) copper plated lead: 1,328 ft/s (405 m/s) .22 LR high velocity
2-grain (2.1 g) copper plated lead: 1,640 ft/s (500 m/s) .22 LR hyper-velocity CCI Stinger

From what I've read on that ballistics URL, it seems that with HIGHER velocity cartridges, with a given bullet weight, — think .223, .204 ruger etc, seem to need a higher twist rate as the bullet weight increases.

So a .223 cartridge:
One revolution every 7 inches “One in Seven” 55-85 grains
One revolution every 8 inches “One in Eight” 50-80 grains
One revolution every 9 inches “One in Nine” 45-75 grains

I just don't know how that applies to a .22LR. I'm only guessing here, that with a lower weight bullet like 36 or 40 grain, it doesn't require a higher twist ratio for bullet stability in flight. But who knows?

[North Country Gal]

Correct. A fast twist would be inappropriate for a 22 LR, given bullet size, type and velocity for the cartridge. As I said, all it would likely do is create more leading in the barrel. Accuracy is a 22 LR barrel is a matter of barrel quality and, especially, chamber dimensions. Match chambers are tighter than standard 22 LR chambers, but are only appropriate in certain types of guns, because it takes more effort to chamber a round in a tighter match chamber. Something you see in bolt guns and single shots, because they can seat ammo with greater force, but won't see in a lever gun.

[markiver54]

Great information...previously had little to no understanding about twist rate. Thank you!

[henry22]

Ok, final thoughts, and this should probably go under "Ammunition" in the forum. But the initial twist rate interest spurred my gripes about ammo pricing.

I'm so ticked off at 22WMR prices. Last year, Cabela's had a sale on the Troy Landry Maxi-Mag 40 grain, 200 round boxes. It was selling for $49.99 CDN + HST: $56.48 for 200 rounds, or .28 cents per round. I could live with that, so I bought about 6 boxes — completely nuts of me. I shot all of it over a few months, and then bought more when it went on sale again later in the year. A friend was selling his 22 mag bolt action, and sold me his leftover 22 mag ammo; 400 rounds for $80 bucks, and I ripped through that ammo too.

I realized that 22WMR is just too expensive to plink with, the way I was shooting it; hundreds of rounds at each range trip. So, I bought an H001T in 22LR, which I've fallen in love with. I can buy a 500 round box of Blazer 22LR for $36.99 - 10% with my discount card, add HST, and you're looking at about $37 all in for 500 rounds. So when I buy 22LR ammo now, it's only Blazer, and I'll typically buy 2000 rounds at a time, for $149.00. I got a $200 gift certificate for Christmas at my hunting store, and bought 4000 rounds (8 boxes of 500), plus I had about 1200 rounds left over from the fall.

Side-note for reference. I also buy CCI .17 HMR FMJ in 50 round boxes for $14.99 at my hunting store. With discount applied and taxes applied, it works out to $15.25 all in. For 200 rounds it works out to an even $61, or .30 cents per round. This makes much more sense than shooting 22WMR to me now. But, still not cheap enough to shoot hundreds of rounds each range trip like 22LR. I'm even thinking about trading my H001M for another .22LR rifle, likely a CZ 455 with a varmint barrel. I love that 22 mag Henry, but it's not for plinking. — No wonder people love 22LR so much.

[John E Davies]

I'm even thinking about trading my H001M for another .22LR rifle, likely a CZ 455 with a varmint barrel.

Unless you need the switch barrel feature, get a nice used 453 Varmint with the adjustable single set trigger. That is a stunningly accurate rifle with common ammo if you use the single shot adapter. Mine loved Mini Mag HPs. The rifle is built better too. If you don’t want a single shot trigger for bench shooting, then a new 457 will work great. It has some upgrades over the 455 like better bottom metal and shorter throw bolt, so you can mount the scope lower. This one would do for me.....
https://cz-usa.com/product/cz-457-varmint-at-one/

John Davies
Spokane WA

[North Country Gal]

John's right about the 453 - IF you can find one - and when you do, they go high, especially the Varmint versions. We have one in 22 LR and one in 17 HMR.