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chip3757
12-10-2008, 4:53 PM
Newbie Question....

Can you shoot the 17 mach 2 out of a riffle chambered for 22 lr. I have a 22 bolt acton. The cartridges are the same length, so it should work in the action but would the .05 difference in bore screw up the barrel?

frigginchi
12-10-2008, 4:57 PM
I'm just guessing it'll get messy. Nothing to support the neck of the case. So you might have a ruptured case and lousy accuracy. But go ahead do it and report back :)

Jpach
12-10-2008, 4:58 PM
its a HUGE difference. dont do it. its the same reason why we dont shoot .22 cals in .25 cal weapons. its just not the same caliber.

.454
12-10-2008, 5:05 PM
Newbie Question....

Can you shoot the 17 mach 2 out of a riffle chambered for 22 lr. I have a 22 bolt acton. The cartridges are the same length, so it should work in the action but would the .05 difference in bore screw up the barrel?

Sure, no problem...it's just a tiny .5 difference after all...:rolleyes:
Your health insurance plan covers everything?

Capt Jack
12-10-2008, 5:14 PM
I have to agree, while its a small caliber, it is still capable of ending your piano playing! Use only the correct caliber in ALL firearms unless you are feeling especially reckless or suicidal.

Oh, and be sure to post up your Kaboom pics...:rolleyes:

chip3757
12-10-2008, 6:17 PM
C’mon,

Their has to be someone out their who has tried it. You could just say…”I know someone who knew someone who....."


You can shoot 38 special in a 357 right?

joel1316
12-10-2008, 6:36 PM
A 38 special is not necked down like a 17HM2. Not the same...

mxpatriot51
12-10-2008, 6:53 PM
You should stick to shooting only calibers that the weapon is actually chambered in. It's kind of a good idea.

NeoWeird
12-10-2008, 7:20 PM
Hey, I can put nitro gylcerin in my gas tank, right? I mean they're both combustable so it should work...

And just so you know, even though they use the same case head (which is like asking if you can shoot .308 in a rifle chambered for .30-06 by the way), their case lengths are very different. You'd probably end up fire forming the case to the chamber and getting part of the case (being as it's a bolt action) embeded into the rifling, meaning you'd have to have serious tools to remove it.

Also, yeah, it's only .050" difference, bet to give you an idea, most headspacing dimenions only allow for about .015" TOTAL difference before things get dangerous for the shooter. Also, the bullet most likely won't just 'bounce' off the walls and fling out in a random, and dangerous direction; that MIGHT happen if you're lucky. Odds are the bullet, being unsupported and with no spin, will nose dive, catch the rifling, try to tumble over itself but instead upstruck the bore and either buldge the barrel or even worse - you could see catastrophic failure of the weapon which can easily lead to loss of sight, limbs, or even life.

Even Kybher pass AKs don't have that loose of tolerances.

chip3757
12-10-2008, 10:19 PM
SAAMI specifications call for a case length of .714" and the same 1.0" cartridge overall length as the .22 Long Rifle cartridge, so the .17 M2 will function in existing .22 LR magazines and actions. Maximum average pressure is held to .22 LR levels, so pretty much any rifle or handgun chambered for the .22 LR could be adapted to the .17 Mach 2. Barrel bore and rifling specifications are identical to the .17 HMR, further simplifying production for gun manufacturers. Hornady has done everything possible to insure the market success of their new cartridge.

Alright, I read this online about the .17 mach 2 and this is why I started this thread....so do you need just a new barrel or some sort of conversion kit?

Bill92869
12-11-2008, 4:59 PM
I accidentally did this very thing. There was no ill effects other than crappy accuracy. I would not have done it knowingly, it was a violation of one of shootings cardinal rules (paying attention and know what you're doing) and a waste of pricey ammo.

Solidsnake87
12-11-2008, 9:58 PM
You should stick to shooting only calibers that the weapon is actually chambered in. It's kind of a good idea.


+1. When I took my hunter safety class our instructor showed up his destroyed 12 guage shotgun from such an incident. Its slightly different, but the guy accidently loaded a 20 guage shell into the gun and forgot it was loaded. When he saw his target, he pumped the gun and chambered a 12 guage shell right after it. That gun is the messiest kaboom I've ever seen.

.22guy
12-11-2008, 10:07 PM
Just buy a Savage bolt action in 17mach2 and be done with it. You could probably get one for 200 bucks or so.

NeoWeird
12-11-2008, 11:17 PM
Alright, I read this online about the .17 mach 2 and this is why I started this thread....so do you need just a new barrel or some sort of conversion kit?

I think where your confussion is coming from is the fact that they are talking about two different cartridges here; the .22 LR and the .17HMR. The .17 HM2 shares similarities between both of them but neither is an easy conversion. What that little snippit was saying was that the .17 HM2 was designed to use already designed and used tools and equipment. It uses the same overall length and case head as a .22 LR (it uses a longer case, the same that the Stinger and other cartridges based off of it use which is about .100" longer than a standard .22 LR) so it can use MOST .22 LR magazines and will fit into any action that can feed a .22 LR. It's bullet however uses the same bullet as a .17HMR so nothing needed to be changed or created for new bullets, and it uses the same bore and SAMMI spec as the .17HMR, so any rifle or barrel designed to use the .17 HMR can also use the .17HM2 by just reaming with a different reamer.

The problem is that the .17 HMR opperates at a much higher pressure than the .22 LR and the .17 HMR action is too long for the .17 HM2. So while it makes manufacturers jobs easier as they don't need to invest in any new tooling outside of the reamers, it makes home conversion a bit difficult. It will absolutely require a new barrel, or if you have a .17 HMR barrel, having it set back and rechambered which will cause you to loose about half an inch of overall length. If the .17 HMR barrel is already on the host gun, then it will also require a new magazine, a magazine block, or will only allow single loading. If this is done the .17 HMR marking on the barrel should be pinged out for safety reasons.

.22 LR actions are more ideally suited to take the .17 HM2, but just because the .17HM2 fits does NOT mean it is safe to rechamber. Almost all semi-auto .22 LR guns are straight blow back and without redesign of the action the .17 HM2 will open prematurely and you will have case failure that will lead to an essentially tiny brass fragmentation grenade just inches from your face (this happens every couple months on Rimfirecentral - the worst I heard of was of a left handed shooter who got brass in his hand and fingers, forearm, cheeks, and one nasty piece that got past his shooting glasses and embedded into his eye lid and had to be surgically removed). This is not a good idea. Some .22 LR actions themselves will not take it; I'd be willing to bet that a Walther P22 couldn't take too much .17 HM2 before the slide started to get battered or get fatigued in high stress areas. Older guns are even worse.

Now when it comes down the .22 LR bolt action guns they are the most ideally suited for this task. They are almost always strong enough to take the additional pressure, do not have the cycling issues that the semi-autos do, and your normal magazine can be used. The problem, as already stated, is that a new .17 barrel (even blank) will run you almost $100 for the BARE minimum. On top of that you have to pay another $60 for a new reamer or pay for a gunsmith to do it for you. Before you know it you're nearing the cost of a new .17 HM2 bolt action gun anyways, and we're not even factoring in getting the barrel refinished.

Save yourself the time, energy, money, and effort and get yourself a rifle chambered in .17 HM2 and have both worlds at your finger tips. This is one of those few instances where a conversion will cost you as much if not more than a new gun.

God bless production lines.