Not sure if anyone here is also a member if Rimfirecentral.com, but over there, the folk have found a way to convert the 10/22 Magnum to a .17 HMR by using a Green Mountain 77/17 barrel and a washer/shim setup.  

It uses the same magazine, bolt, everything else as the 10/22 mag...just the different barrel and the shim and washer to make it all work.

If anyone is interested in making that conversion for themself. Send me an IM and I can get you the instructions for the conversion.  I even have some of the washers and shims available (had a machinist friend of mine make them for me).

The 10/22 is a very cool rifle in .17 HMR.  Accuracy is astounding,  200 Yd. 10-shot groups
under 1.5"  

Adequate power to do close-range rinfire tasks, flat shooting within rimfire ranges and decreased ricochet hazard.  

you can get the green mountian barrel in 17hmr for the 10-22 magnum action. I think that would be easier.

I thought about this conversion and decided not to do so after reading a number of postings on the Rimfire Central Board.  Some comments were to the effect that balloon head empty casings were a result.  

Green Mountain is not allowed to sell their 10/22 magnum action .17 barrels.  I know, I ordered one and the order was "postponed" till such time as Ruger offered their own version of the 10/17.

As far as ballooning case heads goes, there is some minimal expansion, to be sure, but after firing over 2K rounds through mine, I have yet to experience a ruptured case or other dangerous mishap.  



If the shim is made properly (right width) the case expansion is almost nil.  You only really see it on a first shot if there is any lube left in the barrel.  After that, no problems.

Check this out for more info:
www.artifex.ws/hummer.html

More shims came in.

If you have a 10/22 mag and you are interested in getting into the .17 HMR without spending big bucks, this is the way to go.

add a Green mountain barrel (77/17 blued or stainless)

then pick up one of the shim kits for $25 a set...

You're ready to rock.

e mail sent

Got it, and replied to.

Still nothing but success stories from these.  About 2 dozen are in use all over the US and no one yet has had problems with malfunctions, case ruptures or other failures due to this conversion (with one of my kits - I have heard of problems arising from direct conversion barrels that were not made properly.)

http://www.artifex.ws/hummer.html

Hi Artifex,

I am a member over at RFC as well, and the conversion looks cool.  I have a 10/22 LR receiver that needs converted to magnum 1st before the .17 deal.  Do you know where I can get those instructions?  I can't get a reply over there.  Any help appreciated, and if I can get mine converted I will be in the market for your shim kit!

Thanks,

PokeChoke

OU 52 OSU 9 (The POKES CHOKE)

Have you tried asking Chief Dave?  He is one of the LR to Mag pioneers, as well as the original designer of the shim kit that I make.

Try this post: www.rimfirecentral.com/forums/showthread.php?s=&threadid=18610&perpage=15&pagenumber=2I think this has it

Yes, I send chiefdave a PM, but I thought maybe someone else had an idea as well since I hadn't heard back from the chief.  Guess I will just wait to hear from him.

Thanks