Anybody ever heard of a 22 mag upper for an AR?  I am thinking about making one using modified Ruger bbls and bolts.  In my research I have found that the 10/22 magnum bolt is MUCH heavier than the 22lr bolt.  Any other thoughts / suggestions ?

Thanks
rj

what are you going to use for mags?

also, this is just my opinion on the 22mag.   But if it wasnt for the price, i would shoot my 22mags alot more.  but i find the 22lrs just fine.  i think the 22mag is just like the new 17RFs.  they are a great idea, but expensive to shoot.


if you want a 22mag upper, make it.  you never know who will want one and if you got the time/equipment/$$, you may find a niche market.

The Georgia DNR, in all their infinite wisdom, has decreed that on WMA's you will hunt hogs and yotes with small game weapons during small game season. You can use deer weapons during deer season but on most WMA's the actual open season is just a couple of weeks.  When there is an open week the WMA's are usually crowded. During the small game season they are normally deserted.

I have a Sav 22 mag but would like a semi auto . An AR conversion would be neat. The mag problem could be easily solved with an available off the shelf mag. I would start out experimenting with the sav mags.

The bolt will be the real problem. I may try to adapt a 10-22 bolt.

rj

you could use a JAC kit or a m261 kit.  then rechamber the chamber adapter to .22mag.  then find out the weight and the length of bolt travel in the ruger.  then weigh the bolt of the .22lr conversion kit and measure the bolt travel.  more bolt travel than the ruger would be OK, but less would be a pain.  the difference between the bolt weights is how much you would have to add to the .22lr bolt.  to add the weight bore a hole or two and fill with tungsten/ lead/ or the metal they use for balancing stroker engines until you match the weight of the .22 mag bolt.  to make mags cut the .22 llr mag body out of the adapter and weld in a .22 mag body from a Marlin 25N.   the .22 mag should work real nice out of a 1/12" pencil barrel, since it is a slightly larger in diameter than the .22lr.  you might also have to add a heavier recoil spring.  the .22lr bolt face has to be opened slightly, also.

A lot of weight has to be added to any of the 22lr conversions -- the Ruger 22 magnum bolt weighs just over 15 ounces. I do like your idea about using the 22 magnum Ruger after-market barrel.

I am not sure how I am going to tackle the bolt wgt issue. It would be simple enough to make a light buffer spring and just use a std buffer with the travel restricted to just what is needed for the 22mag.

A std rifle buffer is just over 5 oz and a std BC with key is just over 11 oz so creative use of std parts is possible. Machine a std BC so a modified Ruger 22lr bolt fits and pin the ruger bolt in. Experiment with available buffer springs [ carbine spring in rifle length buffer tube would be a start.

I have made music wire coil springs using a mandrel mounted in a lathe.  Takes some experimentation with mandrel dia etc but it is not rocket science.  If would also be possible to create a recoil spring guide rod that a std Ruger recoil spring would slide over.  Slide this assy down the buffer tube then put in the buffer.

A real machinist could make a custom bolt that would fit a std BC and use the std cam pin to lock it in.  You would have to be a little creative with making the bolt stationary in the BC.

Actually the bottom of a std BC would need to be machined to allow the mag to ride high enough to properly align with the chamber. Hmmm.

rj

It might be best to start with a clean slate but I have built a couple of AR uppers in 22 magnum and 17 HMR. I used the M261 unit that I modified the heck out of and got around the bolt weight issue by adding a push rod in the unit that works against an AR buffer. I did my barrels by drilling them out and adding a liner but your idea about using a barrel ment for a Ruger rifle sounds really good.
This is a picture of the M261 bolt setup compared to a normal one above it. Notice the push rod. The modified unit has the barrel liner attached to the chamber adapter and is slid into the drilled out carbine barrel. The rifle versions have the liners made permanent.


22 magnum uppers can be done and to be honest I prefer the 22 magnum round. I stacked the Marlin 22 magnum mags to get a 20 round magazine. I had a higher capacity one but I had problems with it so I cut it back to 20. I have the M261 22 magnum/17 HMR in both a carbine and a rifle. I did this stuff a long ways back and have not done anything more with them since I have moved on to some other projects.

AR-fan  i like the pushrod idea.  that may just be the ticket for a .32acp conversion that has been swirling around in my head.

Quoted: AR-fan  i like the pushrod idea.  that may just be the ticket for a .32acp conversion that has been swirling around in my head.

If you get a 32acp upper up and running you got to show it off here. I know there may not be too many people interested in the 32acp but I have an old AP-15 (Italian Made) that shoots that stuff and I really like it. The rifle is like made out of pot metal but looks like a Colt SP1 and came with 8 and 15 round magazines.

those ap-15 in .32 is what gave me the idea.  then all scorpion SMG parts and mags that have come available over the last few years added the other piece.  once the fall gun shows start up i'm going to start looking for .32 mags.  i would like to use the scorpion mag, but they are double stack.  personally i think that 20rds of .32 acp would be a hoot.  i'm almost done with two other builds, and then it is time to start hardcore on the .22lr, and then tinker with the .32acp AR conversions.

Sounds great -- keep us posted on the 32 acp build.

OK, I got a cheap ruger sporter bbl of ebay so I have something to start measuring and cogitating over.  The ruger bbls are .920 at the front face of the rec with a smaller dia that fits into the rec. This smaller dia is a bit too big to fit through an unmodified bbl ext .  The 920 dia should allow the bbl to be threaded for the AR bbl ext and still have an adequate shoulder.

I have come up with several schemes for the bolt but I think the 261 might be the easiest to make work.  I could machine the front end of the  guide rail so that it fits over the ruger bbl where the chamber end would stick out the back of the bbl ext a small amount [ the thickness of the 261 chamber adaptor's rear face . I would turn down the ruger chamber end so that this all worked out similar to the 261's original bolt / chamber interface.

Move the 261's ejector back and do whatever is necessary for the additional bolt travel . Open up the bolt face.  Then make a pushrod to transfer the bolt travel back to the std buffer. Fiddle the magazine problem and nearly done.


rj

rjay,
    The push rod for the modified M261 can be done as shown in the picture. A short length must be left at the rear to keep tension on the buffer.

Please note that the large retaining screw for the rear block must be set further into the block to allow clearance.

The rear block must be cut back and I think you can get the idea of the amount by the picture that compares an unmodified and a modified rear block.


The modified unit shown uses the original spring setup and a modified chamber adapter (rechambered in 22 magnum) so I could test it in a standard AR upper with a 1:12 twist rate. It works but only because of the amount of gas leak around the chamber adapter. Please not that the ramp on the underside of the bolt must be modified some to allow it to work with the 22 magnum and the M261 ejector must be cut back to allow it to work with the longer 22 magnum round as shown in the picture below.

What did you use for the pushrod ? It almost looks like a section of Allen wrench and the recepticle on the bolt is an allen head screw.

Last night I got to wondering what kept the whole unit from moving rearward with the buffer but I see from the pics that there is a tab with a section of leaf spring that fits in the CH tunnel and bears against the tang of the lower rec when the action is closed.

Thanks
rj

Quoted: What did you use for the pushrod ? It almost looks like a section of Allen wrench and the recepticle on the bolt is an allen head screw.

I got a piece of steel rod that happened to have a round head on it and long enough to allow me to cut it to the correct length. The rod doesn't need to be some super hard steel. I put a small rubber O-ring just behind the push rod head to keep it from mushrooming.


You are right about the little spring tab holding the unit in place.

I have come up with a better plan. Numrich has an Anschutz 22 rimfire bull bbl blank that is 1.250 od. The advantages are obvious. No need for an AR bbl ext, just machine the blank to fit the rec, drill it for the locating pin, ream the chamber and do the extractor cut.

I just ordered the blank and a reamer. Now I am going to call sarco and get an M261 kit coming.

rj

Oh darn, and I've got fluted 77/22 magnum barrels that I was thinking about making an adapter so it would slip into the AR receiver -- I was hoping you would take the lead and show me how you did it.

The barrel blank sounds great -- will you be doing the machining or will you take it to a shop?

I did some corresponding with Randall and using the original AR bbl ext is not going to work as easily as I thought. If you want to use a ruger bbl I would just machine up a steel sleeve that duplicates the outer dimensions of the AR bbl ext but is bored to be an interference fit on the ruger bbl OD. Then press the ruger bbl into the new sleeve and once you get everything lined up [ chamber face, bbl ext locating pin ]  pin the ruger bbl to the sleeve.

Now that I just added the above part in parentsis I would just drill the sleeve to rec locating pin hole down through the sleeve and into the the ruger bbl and use that pin to positively lock the ruger bbl into the sleeve. You would have to make a custom pin from drill stock.

Seems a lot less trouble to do a little lathe work on the Anschutz bbl.

I have 2 machinists I can call on to do custom work. One is a damn good machinist and the other is your basic mad scientist.

rj

Quoted: I did some corresponding with Randall and using the original AR bbl ext is not going to work as easily as I thought. If you want to use a ruger bbl I would just machine up a steel sleeve that duplicates the outer dimensions of the AR bbl ext but is bored to be an interference fit on the ruger bbl OD. Then press the ruger bbl into the new sleeve and once you get everything lined up [ chamber face, bbl ext locating pin ]  pin the ruger bbl to the sleeve.

That is exactly what I was going to do -- the reason was there seems to be easy access to used and new Ruger model 77/22 magnum barrels. I figured if it was cheap enough to make the adapter it would cut the cost of the overall setup.  

Quoted: Now that I just added the above part in parentsis I would just drill the sleeve to rec locating pin hole down through the sleeve and into the the ruger bbl and use that pin to positively lock the ruger bbl into the sleeve. You would have to make a custom pin from drill stock.

Good point -- I didn't think about using the pin to lock it all together!

Quoted: Seems a lot less trouble to do a little lathe work on the Anschutz bbl. I have 2 machinists I can call on to do custom work. One is a damn good machinist and the other is your basic mad scientist. rj

I need to locate somebody to do the work for me -- I have not had a chance to really check around yet. I do most of my own work by hand but cutting an adapter needs to be done correctly with close tolerances or the whole thing is a bust -- I don't have the equipment to do that.

This picture is of a Green Mountain 20" Ruger 77/22magnum blued fluted bull barrel. The type of adapter is similar to what is on the barrels chamber end.

This is a close-up of what I was thinking about.

The adapter can continue forward to cover the Ruger notched area and still clear the barrel nut.

Back when I had my fab shop I had an old south bend lathe for making various spacers and other "semi-precision" parts. When ever I needed something truly precision I let one of the real machinists do it.  It's nice having buds that are professional machinists .  

rj

Quoted: Back when I had my fab shop I had an old south bend lathe for making various spacers and other "semi-precision" parts. When ever I needed something truly precision I let one of the real machinists do it.  It's nice having buds that are professional machinists .   rj

You are so right -- I've got to start looking for a shop that can make the adapter for me. It's funny, I don't really need it since I already have the setup but I relined a GI barrel and I feel that one of these Aftermarket Model 77 barrels would give me better accuracy although I'm getting under 1/2" at 50 yards.

This was my 22 magnum upper -- I swapped out a bunch of parts to build another nice magnum upper.

This is the upper now. Not shown is a 3x9 scope I put on it. It makes a nice field small varmint rifle and is actually lighter than a Ruger 10/22 magnum.

The magazine on this is my 5 round range mag with a dummy 20 round body. By the way, building the setup takes some time but kinda just falls together nice -- the hard part will be setting up the mags!
I would love to have one of these with a nice fluted target barrel on it!

I am going to get an AutoMag pistol mag and adapt that to a steel AR mag. Small sections of sheet metal will get welded to the pistol mag and a series of holes and slots put in the AR mag and I will use sheet metal screws to make it all adjustable. Once I have it properly aligned and feeding reliably I will weld it up solid.

rj

That sounds like a real good idea. You already seem to know that the real problem with the 22 magnum setup is first, finding a good magazine and second, getting it to work. My first was also adjustable but it still took awhile to get it right. I hope to see some positive results with your project real soon.

Did the 32 acp go by the wayside or is that still in the works?

WOP [ waiting on parts ]

If the automag mag works out it would be worthwhile to try and make a mag block out of some sort of plastic [ urethane ?? ] that would accept the mag and have it's own mag catch.

rj

Well, Santa in Brown came today bearing gifts !!!  Got the Anschutz bull bbl and the clymer 22 mag reamer. I had to polish the pilot on the reamer to get it to go in the 22 LR bore . Not unexpected. Now all I need is for the M261 kit to arrive from Sarco and I can get down to the nitty gritty.

rj

I love getting into stuff like this -- I've got a project kinda ready to get started but you got me interested again in the rimfire magnum stuff. The reason I was thinking about the adapter for the Ruger barrel to the AR upper is the fact that once you get the 22 magnum setup up and running the next logical project is the 17 HMR. There are a lot of barrels chambered in 17 HMR out there just waiting for you to try one! I just ordered a SS fluted 20" heavy barrel in 17 HMR but it's for another project. Keep the pictures coming -- it's always cool to see somebody start a project like this and be able to follow along as it progresses. By the way that barrel must weigh a ton!

I figured out how I am going to do the side rail. I am going to remove the m261 chamber adator and machine a slot in the end of the new bbl to accept the leg of the side rail. I will do this before we machine the locating pin for the bbl. This way if we need to rotate the bbl to move the side rail up or down it is no problem.

Numrich also had some .875 22 mag bbls for less than $40 if I remember correctly. You would still have to get a reamer.

rj

I have been thinking about the Ruger bbl conversion and I think you are going to have some issues making a sleeve. The wall thickness of the sleeve is only going to be about .040" which is too little to allow for much of an interference fit.  I think a large dia bbl blank machined to duplicate the std AR bbl ext is going to give the best and easiest conversion. You can get an A&B .224 blank from Midway for $80 and a PTG reamer is only $40.

I have found some 22 mag 're-loading' info if you are interested.

rj

Quoted: I have been thinking about the Ruger bbl conversion and I think you are going to have some issues making a sleeve. The wall thickness of the sleeve is only going to be about .040" which is too little to allow for much of an interference fit.  I think a large dia bbl blank machined to duplicate the std AR bbl ext is going to give the best and easiest conversion. You can get an A&B .224 blank from Midway for $80 and a PTG reamer is only $40. I have found some 22 mag 're-loading' info if you are interested. rj

You're right and I would not want to turn the Ruger type barrel down to the diameter of the stub that would normally fit into the ruger receiver and then build an adapter. Since I already have the reamers, crowning tools and stuff the only thing I would need would be to get somebody to cut me a .224 barrel blank to what ever specs I wanted and I'd do the rest. I just got into a 10/22 type project and have found that barrels seem to be easy to come by and I really only wanted to see what they would do up against an M261 unit. Volquartsen is coming out with 20 round mags for the 10/22 magnum and the 10/22 magnum converted to 17 HMR. I just finished the conversion to 17 HMR this afternoon although this is a target rifle. I'll build another 10/22 magnum and use that one for the 20 round mags.

Actually I thought about it some more and what you would do is make the sleeve OD oversize, press it on the ruger bbl and then have the od turned down to the proper DIA [ app 1" ] while the sleeve is on the bbl [ leaving the shoulder for the bbl nut to bear against]. Then drill the locating pin after aligning the extractor slot. This would assure the tightest fit of the bbl to the sleeve. I don't think I would use a bull bbl with all that weight out in front of the thin sleeve.


rj

Quoted: I have found some 22 mag 're-loading' info if you are interested. rj

I've seen threads about people unloading a live rimfire round and then reloading it to their own specs -- if this is what you're talking about I'd love to see it. I'm happy with the ammo that's available but I love to read about stuff like this.

www.gun-tests.com/performance/apr96reloading.html

I have a box of 223 dia 45gr "hornet" soft points it would be interesting to try in my 22LR bore.

Have you ever crono'ed your 16" 22 Mag?

rj

Quoted: www.gun-tests.com/performance/apr96reloading.html I have a box of 223 dia 45gr "hornet" soft points it would be interesting to try in my 22LR bore. Have you ever crono'ed your 16" 22 Mag? rj

That is some very interesting information -- thanks for the link! I've never had the chance to check the velocity (crono'ed) on the carbine. The carbine started out as a test bed and worked out so well that I decided to use it as a field gun. The liners can be slid in and out of the drilled out barrel so I can change calibers. The big ones are the 22 magnum and 17 hmr and the lighter ones are the 22lr and 17 Mach2.

This is the carbine with the 22 magnum barrel liner installed and the 17 HMR below. The mags are the 5 round range mag, some 15 round mags and a 25 round mag. The 20 round mag has a slide on cover but it's not shown. The actual barrel liner lengths are 17.5".

I think I am going to try some reloading. I dug out my 45gr Hornet bullets and they turn out to be 224 instead of 223 but I am going to try it anyway. I have some cheap Winchester ammo that would be perfect for experimenting with. I am going to get a collet and shell holder from Midway and some hornet dies off Ebay . I am DEFINIETLY going to wear a full faceshield when working with this rimfire stuff .  I will probably just shoot the reloads of of my Savage.

Hopefully my m261 kit from Sarco will show up in the next couple of days.

rj

Quoted: I think I am going to try some reloading. I dug out my 45gr Hornet bullets and they turn out to be 224 instead of 223 but I am going to try it anyway. I have some cheap Winchester ammo that would be perfect for experimenting with. I am going to get a collet and shell holder from Midway and some hornet dies off Ebay . I am DEFINIETLY going to wear a full faceshield when working with this rimfire stuff .  I will probably just shoot the reloads of of my Savage. Hopefully my m261 kit from Sarco will show up in the next couple of days. rj

Do you mean You're going to shoot your reloads in a Savage bolt action rifle? That would be a very good idea -- if you get your M261 setup working please don't try any reloads in it.

I will only shot the reloads in my Savage. They will probably end up a little long anyway.

There are some Pacific 22 Hornet dies on Ebay right now. Should work perfect in my 30+ yr old Pacific press

Brain fade on the typing in my other post

rj

I hope the M261 shows up -- you have a bit of work ahead.

A startling development in my 22 mag conversion....... my 'back ordered' M261 kit showed up from Sarco !!!!!!  This kit looks new. Now I have to start turning a large, thick walled tube into curlicues.

rj

Quoted: A startling development in my 22 mag conversion....... my 'back ordered' M261 kit showed up from Sarco !!!!!!  This kit looks new. Now I have to start turning a large, thick walled tube into curlicues. rj

Well, that was good news! You were thinking it would never show up!

In looking at the m261 it is obvious that you save a ton of work by using this kit as the basis for the 22mag conversion. The ejector is simple to cut back and the lower part of the bolt will be simple to modify to work with the longer cartridge. With your pushrod idea the only thing 'difficult' will be chucking the bolt up in a 4 jaw lathe chuck and opening up the bolt face.

What did you use for a buffer spring ? My 22mag upper will probably end up on a Cavalry Arms polymer lower with the carbine buffer and spring.

rj

Quoted: In looking at the m261 it is obvious that you save a ton of work by using this kit as the basis for the 22mag conversion. The ejector is simple to cut back and the lower part of the bolt will be simple to modify to work with the longer cartridge. With your pushrod idea the only thing 'difficult' will be chucking the bolt up in a 4 jaw lathe chuck and opening up the bolt face. What did you use for a buffer spring ? My 22mag upper will probably end up on a Cavalry Arms polymer lower with the carbine buffer and spring. rj

You have discovered why I went for the M261 unit for the 22 magnum setup. It's all there -- it just needs to be adjusted to work with a longer cartridge.

I started out using a lower with the full length buffer tube. In the full length tube I used a carbine spring (no plastic spacer in there) and a carbine buffer that had the weight modified. I changed the weight around on the buffer till I got the setup to cycle and still see a normal case head on the fired cartridge. This setup does not like any movement of the weight in the buffer so when you're adjusting the weight be sure the platic buffer tip compresses it all nice and tight each time. I started out using one of the original buffer weights and some Daisy BB's to play with the weight. If I needed a spacer to take up empty space, I used a piece of wooden dowel. In my carbine I use the same weight buffer and just cut a carbine spring back some. I can weigh my buffers and measure my springs if you want but there will be some operating differences between my setup and yours since I did my own barrels by relining them. The Redman liners are known to be tighter than a normal 22lr bore and you've actually gone to the larger .224 bore. You may not need as much weight as me but always start heavy and work back from there. When you first start, load single rounds and test -- if you have a mag in place and the cartridge case goes kaboom the magazine will get screwed. You can always test the full cycle after you get the setup firing ok. Do not forget to wear safety glasses.

The ramp on the under side of the bolt will need to be played with depending on the magazine setup you will use. There is a step in that ramp and that was for holding the bolt open when using 22lr rounds. The rear metal block needs to be cut back to allow the bolt to move back further and again, may be different than mine depending on the magazine setup you use.

This 22 magnum uppers work great -- when you get your's started, be sure to take pics and post them!