Important Safety Notice On The New .17 Cal Mach 2

[Harry Tuttle]

"Important Safety Notice On The New .17 Cal Mach 2"

http://www.volquartsen.com/Mach 2.htm

This exciting new rimfire cartridge will undoubtedly inspire consumers to want to modify some of their existing .22 caliber rimfire semi-automatic rifles to accommodate it._ To achieve the performance level that this cartridge offers and consumers have demanded, special blends of powders were used which cause semi-automatic firearms to cycle faster than with existing .22 caliber rimfire ammunition. This difference requires special bolt designs to maintain a safe shooting condition. Reputable firearms manufacturers that follow specifications set forth by the Sporting Arms and Ammunition Manufacturers' Institute have designed their Mach 2 firearms with special care being given to this requirement.


Consumers desiring to modify existing semi-automatic firearms with after-market components are strongly cautioned that modification must be made to the bolts as well as the barrel. Modifications should only be made by competent gunsmiths properly trained in the modifications required.


In response to this, the following warning appears on each box of ammunition supplied by CCI:


'WARNING; To avoid serious injury use this ammunition only in firearms that have a barrel/chamber with standard SAAMI sporting dimensions for this Mach 2 .17 caliber cartridge AND a bolt specifically designed for this Mach 2 .17 caliber cartridge."

see also
http://www.tacticalsol.com/17 mach 2/mach2.htm

 

[Preacherman]

Harry, thanks for posting this. Good information to have!

 

[jojosdad]

Is this a different round than the .17 hmr?

 

[Harry Tuttle]

yep

http://www.hornady.com/story.php?s=51

After Hornady’s phenomenal success of the .17 HRM cartridge, they set out to develop a .17 caliber cartridge based on the .22 Long Rifle cartridge case. Aguila has also been working on a similar project, but the Hornady cartridge seems to be taking the lead at this point. Calling the new shorter seventeen the .17 Mach 2, or HM2 for short, they basically necked down the .22 CCI Stinger case, which is longer than the standard Long Rifle case, to accept their 17 grain .17 caliber V-Max bullet. The little seventeen shoots much faster and flatter than a high-velocity .22 Long Rifle cartridge, and suffers less wind deflection in spite of its lighter weight, due to a much shorter time-of-flight._ Chronograph readings at a temperature of eighty-five degrees, with the screens twelve feet from the muzzle, showed the .17HM2 achieved a velocity of 2072 feet per second (fps) from the 16.5 inch Tactical Solutions barrel. I also fired the .17 HM2 from a Tactical Solutions twenty inch light profile barrel that was installed into a Ruger Model 77/22 action. The chronograph readings were actually a bit slower from the longer barrel, achieving only 2052 fps. This shows that the .17 HM2 is a very efficient little cartridge, achieving maximum velocity from a relatively short barrel. The new seventeen ammunition is slated to sell for less than the .17 Magnum ammo, making it a bit easier on the budget than the larger seventeen rimfire cartridge.

http://www.gunblast.com/TacticalSolutions1022.htm

 

[waktasz]

So it's slower than a 17HMR? Is the bullet bigger? What is the big stink all about?

 

[Harry Tuttle]

same bullet
just higher pressure than a 22lr
if you want to shoot the new M2, just replacing the barrel on yer 10/22 is not advised

 

[c_yeager]

Weird, people didnt seem to have any trouble swapping out a few parts of their 10/22s in order to fire the HMR which is a hotter cartridge than this Mach 2. Not that i would recomend doing so.

 

[Guntalk]

The .17 M2 can be chambered in firearms built for the .22 LR, which means a LOT more guns will be chambered for it than the HMR.

Expect 2050fps muzzle velocity from an 18-inch barrel. It holds up well in handguns, not losing as much velocity as one might expect.

In fixed-breech guns, the conversion can be fairly simple. Autoloaders, however, are different. The faster bolt velocity with this round requires that the bolt be heavier.

The .17 Mach 2 is going to be bigger than the .17 HRM.

It is even more accurate than the .22 LR. Expect 1-inch groups at 100 yards!!!

 

[tulsamal]

I expected the Mach 2 to be a big hit but that was because the original idea was that guns like a 10/22 would be able to be converted with a simple barrel change. The American Rifleman had a whole article about it and said that was the most important design idea. And then it comes out and the semi-autos start to have problems. So then these warnings came out. It's really too bad.

I suppose it will still be a success but it is a design miss. If I want to convert my 10/22, I'm going to have to buy another bolt to go with it. And the Ruger MK II is the same way. That company that makes the replacement top ends WAS selling Mach 2 uppers but not any more.

http://www.tacticalsol.com/17 mach 2/mach2.htm

I still don't have either one of the .17 rimfires but I would like to get one some day. Other guns seem to always suck up the money.

Gregg

 

[PromptCritical]

Magnum Research sells a graphite M2 barrel for 10/22's. It comes with a bolt adapter for this very reason.

www.magnumresearch.com

 

[Poodleshooter]

Weird, people didnt seem to have any trouble swapping out a few parts of their 10/22s in order to fire the HMR which is a hotter cartridge than this Mach 2. Not that i would recomend doing so.

Nope-only 10/22's chambered for the .22 Magnum can retrofit for the HMR. The folks you see swapping in 17HMR components are doing so with .22 magnum chambered weapons. Regular .22lr 10/22's can't just swap barrels to shoot 17HMR.
I suspect that regular .22lr 10/22's could be retrofitted to fire 17HM2 with simply a new barrel and a plastic bolt buffer to slow down the recoil. That might suffice in lieu of a whole new bolt. Whether function or pressure concerns are the issue here, I'm not sure.

 

[c_yeager]

Nope-only 10/22's chambered for the .22 Magnum can retrofit for the HMR. The folks you see swapping in 17HMR components are doing so with .22 magnum chambered weapons. Regular .22lr 10/22's can't just swap barrels to shoot 17HMR.

Ah, I believe that you are correct. Thankyou for pointing that out.

 

[wintermute76]

There are some of the .17 HMR conversions running the standard bolt, like the "Chief Dave" conversion on the10/22 LR. If I recall tho, there were some instances of bulged cases.

 

[gewehr44]

Perhaps I should start a new thread but....

The HM2 interests me & I'm curious if there is anything special with the design & construction of the round that will keep it from becoming as inexpensive as the good ole 22LR??

 

[Preacherman]

anything special with the design & construction of the round that will keep it from becoming as inexpensive as the good ole 22LR??

Yes - manufacturers' profits! There is little reason why the .17 HMR should not have come down in price to a significant degree, given that initial tooling-up has been paid for: but it's as expensive as ever. The .17 Mach II will do the same, IMHO. Manufacturers introduce new calibers and cartridges for only one reason - to make money. They don't do it because they love shooters and want to give them something new to play with! I'm afraid that neither .17 will ever drop to .22LR levels, although technically there's no reason why they couldn't drop at least 50% from where they are now.

 

[shermacman]

Thank God that there is another choice in the .17 caliber market! And to think that the newest offering is slower, has less ft-lbs of energy and a loopier trajectory! Requiring different barrels, bolts, magazines! None of it interchangeable!

The answer to all of our prayers!

 

[Cindog]

Preacherman,

In my area the price on 17HMR has come down significantly and I have been able to pick up 50 count boxes for 6.99 - 7.99. Not too bad considering that when 17HMR first came out it was routinely priced at 9.99 to 11.99. The few 17M2 50 count boxes that I have seen have been priced at 5.99. Regardless, I hope you are right and the prices of the 17HMR and the 17M2 go down even further as the rounds gain popularity.

Scott

 

[sumpnz]

Part of the reason for the higer cost is the fact that they're using premium jacketed bullets in the 17's and much cheaper solid lead, or simple copper plated bullets in the 22's. If they used cheapo bullets the price would come down quite a bit. Not all the way, but it would be enough to notice.

 

[gewehr44]

Good point, sumpnz. Perhaps when (if?) they get popular enough, there will be bargain type ammo that will be low priced for plinking. I don't need a premium bullet to be punching paper & cans.

 

[Onmilo]

From what I understand, the higher breech pressures associated with the .17 HMR and .17 HMR2 require a smaller firing pin port and a thinner firing pin in semi automatic weapons because the case rims tend to flow back into the larger standard .22 caliber cartridge sized firing pin ports during the cycling stage.
The .17 caliber case heads can or may also rupture during cycling when fired against a standard bolt face in a semi automatic weapon.
The manufacturers will in all likelyhood offer conversion kits for semi automatic rifles already in use but the kit will be comprised of a barrel and fitted/headspaced bolt assembly and probably a stronger than standard recoil spring.
Ruger, it appears will offer .17 HMR2 conversion uppers for the Mark 2/3 and 22/45 pistols but since these are the serial numbered part you will buy them just like a complete pistol, 4473-waiting period-background check-etc.