New Rimfire Cartridge - .21 Sharps

[grauhanen]

Here's something to relieve some monotony or boredom.

There's a new rimfire cartridge, the .21 Sharps. For starters, it uses a .22LR casing and a non-heeled 25 grain bullet. Muzzle velocity is 1725 fps. If I read correctly, the barrel is a 1:12. Existing rifles that can swap to a .21 barrel should be able to use it.



For more details, see h t t ps://www.thefirearmblog.com/blog/2023/07/10/21-sharp-rimfire-cartridge-winchester/

 

[Grain]

That it uses LR 'brass' and should be usable in a lot of current rifles with only a barrel change (thinking 10/22 and 455/7) may make it moderately successful. Not sure what the goal of it is? Improved accuracy? Will need to show some significant advantage over LR, or even 17 HM 2 to become mainstream, in my humble opinion.

 

[MilitaryCollectorMark]

That's interesting! A new rimfire cartridge in how many years?

 

[Suther]

Interesting idea, but I don't see it going anywhere. 17hmr is faster, 22mag is more powerful, and 22lr has match grade ammo. 22mag and 17hmr already suffer from a lack of high quality ammo. Plus you've got millions of guns chambered in 22lr in people's hands.

I'm going to bet this ends up like 5mm mag, those who have it love it but the guns are rare and ammo isn't even made most of the time.

That's interesting! A new rimfire cartridge in how many years?

17wsm was 2012. I can't think of anything more recent? And it isn't very popular despite hitting 3000fps with a rimfire (2600fps w/25gr bullet, which would likely have a better SD and BC than the 21 sharps). Meanwhile this new thing is very similar to CCI Stingers in 22lr...

 

[MiG25]

Yeah, maybe it'll be more successful than the 17 HMR2.

 

[horseman2]

With all the enthusiasm I can muster . . . it parallels "Tits on A Boar" which of course serve a genetic purpose!

 

[Mystic Precision]

1 of the comments on the TFB page... "John" says...

"I notice that quite a few here regard this as pointless, a solution in search of a problem. It isn't. California banned lead hunting ammo some years ago, including rimfire ammo. Living behind enemy lines as I do (California), I can say with some authority that efforts to produce satisfactory lead free .22LR by the big ammo makers have pretty much failed, rendering millions of rimfire hunting arms in the state essentially useless. The heel base bullet design simply doesn't lend itself to non-lead bullets. Other states are following in the PRK's footsteps in a growing trend. The same thing is happening in Europe. I would guess that this is Winchester's attempt to prevent this trend toward lead free ammo from killing off the world's most popular cartridge, not to mention one of their biggest revenue streams. If so, it's the sensible approach. To replace the heel based bullet of the .22LR requires either increasing the case diameter, or reducing the bullet diameter. The latter will allow millions of guns to be kept in service, by either rebarreling or boring out and sleaving the existing barrel."

now it makes some sense...

Jerry

 

[tiriaq]

It does away with the heeled bullet - which is one feature that complicates obtaining best possible accuracy from a .22LR. The heeled bullet is an archaic 19th century design.
Whether it catches on is another matter.

 

[Grain]

1 of the comments on the TFB page... "John" says...
"I notice that quite a few here regard this as pointless, a solution in search of a problem. It isn't. California banned lead hunting ammo some years ago, including rimfire ammo. Living behind enemy lines as I do (California), I can say with some authority that efforts to produce satisfactory lead free .22LR by the big ammo makers have pretty much failed, rendering millions of rimfire hunting arms in the state essentially useless. The heel base bullet design simply doesn't lend itself to non-lead bullets. Other states are following in the PRK's footsteps in a growing trend. The same thing is happening in Europe. I would guess that this is Winchester's attempt to prevent this trend toward lead free ammo from killing off the world's most popular cartridge, not to mention one of their biggest revenue streams. If so, it's the sensible approach. To replace the heel based bullet of the .22LR requires either increasing the case diameter, or reducing the bullet diameter. The latter will allow millions of guns to be kept in service, by either rebarreling or boring out and sleaving the existing barrel."

now it makes some sense...
Jerry

That does add some context to the conversation, thanks for posting.

 

[Buck1950]

I think experimentation s/b expanded with DU 22LR

 

[sillymike]

That's interesting! A new rimfire cartridge in how many years?

The 17HM2 was introduced in 2004... In 2012 Winchester tried the 17 WSM. Don't know of anybody who bought one.

 

[trky chsr]

That's interesting! A new rimfire cartridge in how many years?

Not sure how long ago exactly but 17 Mach II is pretty recent I believe. TC

 

[sk8snwmx]

I love rimfire, I don't think I will every buy one... I bought a .17hmr once, that was enough of a waste of time for me...

 

[grauhanen]

It does away with the heeled bullet - which is one feature that complicates obtaining best possible accuracy from a .22LR. The heeled bullet is an archaic 19th century design.

Why does the .22LR's heeled bullet itself hinder or complicate accuracy?

 

[Raton57]

I have some 22RF with zinc bullets made in Europe haven't had time to shoot it yet. I have all of them almost the 17WSM has one hell of a crack to it. I have shot it at still plates and it dents them in .

 

[tiriaq]

The heel upsets on firing. Obtaining absolutely uniform, consistent upset is a challenge. A groove diameter bullet eliminates this.

 

[Leuchtkafer]

The heel upsets on firing. Obtaining absolutely uniform, consistent upset is a challenge. A groove diameter bullet eliminates this.

Yes, it immediately obturates up to the chamber diameter upon exiting the casing. If there is a malformation in the chamber, say being not in perfect alignment with the bore, when the heel is swaged down to bore diameter as it exits the chamber, the heel elongates and will not do so uniformly, thereby disturbing the centre of gravity.

 

[guntech]

If this new .21 cartridge can be mass produced matching .22 accuracy and for the same price as current .22 ammo, it has a chance for success eventually...Firearms would have to be produced at reasonable prices and .22 ammo would have to go up considerably in price. The average shooter is very price conscious (cheap). If the 17 Mach II ammo was cheaper there would be more guys using them.

 

[grauhanen]

The heel upsets on firing. Obtaining absolutely uniform, consistent upset is a challenge. A groove diameter bullet eliminates this.

It may be not so much the .22LR heeled bullet itself that is the most serious problem.

For the general reader, a heeled bullet is one which has the same diameter as the casing. The part of the bullet inside the casing is the heel. Below is an example of Cutting Edge .22LR bullets that are heeled.



The .22LR (and .22 Long and Short) bullets from ammo makers are different from other heeled bullets. The .22LR has a heel cavity and hence a rather delicate heel base along the edge of the cavity. The edge is relatively narrow and easily malformed.



With the .22LR bullet's more complicated heel geometry, these have the potential to be more likely to be manufactured inconsistently. Other heeled bullets don't have a heel cavity. They are flat at the bottom. This will no doubt result in imperfect bullet characteristics inimical to accurate performance. Once fired, the bullet that doesn't have as nearly a perfectly shaped heel base as possible will be compromised in performance.

Yes, it immediately obturates up to the chamber diameter upon exiting the casing. If there is a malformation in the chamber, say being not in perfect alignment with the bore, when the heel is swaged down to bore diameter as it exits the chamber, the heel elongates and will not do so uniformly, thereby disturbing the centre of gravity.

Along with the chamber and its alignment with the bore, the entire bore itself, each of which is unique in varying dimensions and concentricity, contributes to further bullet obturation. This in turn affects bullet center of gravity. Since soft lead projectiles like .22LR bullets are practically impossible to manufacture to be perfectly balanced, the changes added by individual chambers and bores causes the bullets to be obturated distinctively by the bore through which they pass. This explains at least in part why two different rifles may shoot the same good lots of ammo with different results.

 

[wallz]

I would be shooting a 17 wsm rifle now, if there was any ammo available in Canada, but I don't see that changing anytime soon. I built up a Rimx with the intention to rebarel to a 17wsm, but at the time couldn't find a barrel in Canada, much less any ammo, so have gone on to other pastures for now.

I will be following this new cartridge and see if it gets any traction and availability.