Change .22LR to WMR?

Grandaddy53

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Is it possible to have a .22 LR chamber bored out to take .22 magnum ammunition? I've got a nice little single shot that I'd like to get more range out of.
 
No reason why not. Just keep in mind that the bore/grooves of an LR is a few thou smaller than the WMR. As such, you will need a reamer to suit. What kind of single-shot is it and how robust is it? A break action will be infinitely strong for such a conversion but some of the other action types are not.

You will get some dolts who whine about the bore size being different, however, the difference is utterly negligible. PO Ackley (heard of him?) rechambered a 30-06 out to 35 Whelen with a long throat, and fired it without any detectable increase in pressure or causing any damage. Test controls: same bullet weight for both calibers and same powder charge.

EDIT: Actually, I am lying, both WMR and LR rounds have identical PSI Max. of 24000 PSI and virtually identical proof loads. According to SAAMI the minimum proof for LR & WMR are 31000 PSI & 32000 PSI respectively and the max proof loads are 34000 PSI & 35500 PSI, respectively. Convert away without any issue.

Source: http://www.saami.org/specifications_and_information/publications/download/208.pdf Page 67
 
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Depends on the rifle in question...some single shots are robust enough to handle it, some are not. (An example of a "not" would be a Cooey single shot. The only locking lug is the bolt handle which is brazed on). You'll also want to be sure you can feed and extract the longer round.

Cost is a serious factor. By the time you've paid for the the re-chambering, and possible bolt work(bigger rim on a .22wmr) you might be better off selling your current gem and just buying a .22wmr.

All negativity aside, if you do pursue the project please share the experience.
 
the bore/grooves of an LR is a few thou smaller than the WMR. As such, you will need a reamer to suit.
It is a lot less than "few thou" smaller.
You are right that you may need a "reamer to suit", as it should be different
than a regular reamer used to chamber a designated 22 mag bore.







OP should understand that if his "single shot" is a bolt gun,
it might not have enough bolt travel to accommodate a magnum.

Diameter of the rim is also very different (magnum is larger).
Thickness of the rim is different (magnum is thicker).
So in addition to the re-chambering, a new pocket for the rim should be cut in the bolt or the barrel,
depending where the pocket is in that particular gun.
The extractor(s) might need some minor re-fitting, as well as the firing pin and spring.
 
Thanks for the info guys, maybe I'll keep the single as is for my grandson and buy a new .22 WMR for me. I'll have to disguise it as a broom to sneak it into the house, might need another safe too.
 
Blastattack are u saying the 30-06 308 dia bore was rechambered to 35 whealan 358 dia bore and fire the 35w through the 308 bore.

That is is why I bolded, underlined and italicized the word rechambered. Ackley enlarged the 30-06 chamber to fit the .35 Whelen. He did so by enlarging the throat and lengthened leade (I think that it the right word) and fired .35 Whelen through the same barrel.

Some more reading: http://www.tactical-life.com/magazines/rifle-firepower/long-gun-legends-p-o-ackley/2/

I wish I knew which book the test was originally published in. Im pretty sure the test was actually published by PO Ackley in one of his books.
 
Do you think the information in the 4th post down by Dr. Lector would not apply to your question? Only you can decide if it would be worth the try.

Gee, thanks for the extra info. You must have been bored and wanted the extra post count. I was looking for a response from someone who may have had some experience with the savage rascal, not the peanut gallery.
 
The Rascal has a pretty short bolt movement so a 22mg case would probably be to short. I will have to look at the way the bolt is made on mine to see how they put the handle on the bolt also.
 
Gee, thanks for the extra info. You must have been bored and wanted the extra post count. I was looking for a response from someone who may have had some experience with the savage rascal, not the peanut gallery.

Your first post was a general question asking if the rascal would be a good candidate for a conversion. I was merely asking if you thought the information already given might also apply to your gun and, if so, if you thought it would be worth the cost to have it done.
With the net, one has no idea how the typed word will be received on the other end in regards as to how it was intended to be interpreted. I will admit I could of perhaps worded my question a bit differently so I apologize that I got you fired up.
 
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