17mach2 to 22lr swagger barrel

[jrcanoe]

I'm thinking that once the mach2 barrels come out it would be relatively easy to ream out the chamber neck area and ream in a long forceing cone. 77/17 swagger here I come. 1$ abox ammo 17 velocities the accuracy is the only big question.

[gunnut69]

Better verify the gas handling capabilites of the 77 ruger first as I'm gonna guess your gonna find out first hand.  The bullet you'd be trying to create would be more than twice as heavy as that the round was design to handle and while the 22 LR bullet is lead it will generate more pressure than you'd want to think about trying to contain in a LR rimfire case.  I'd bet burst cases would be the norm.. Also accuracy would well and truly be the pits.  Like trying to shoot 110-130 grain 224 bullets in a 223 rem.  The twist rate wuldn't be nearly fast enough to handle the bullet length..

[longgun]

Your Ruger 77 will handle the pressure ok.   I did some experimenting with my 77 couple years ago.  Only I made mine to use a 20 cal barrel.   Perhaps I used too fast a twist but my rifle was not accurate as I wanted.  I was grouping about 1.5 " at 100 meters.    Also checked velocity with my cronograpy, and found that the velocity was slower than my standard 22 LR.   Also did some checking and found that the faster the twist rate the slower the velocity  of the 22's that I checked.   Was fun to play with though.   Have a 20 cal swager reamer you can use if you want to give it a try......  Don

[jrcanoe]

Longgun
I think the mach2 barrels will come with a 1 and 9 twist, which I hoped would be fast enough but it never occurred to me it could be too fast. I read the standard velocity 22lr had less velocity once extruded to 17 but the hyper-velocity 30grainers clocked at 2100fps out of a 17 swager. Thats equal to the mach2 but with nearly twice the bullet weight and 1/5 the cost for ammo. Like you said it should be fun to play with.

[KN]

You don't seriously think you can create more velocity by swagging a bullet down to a smaller diameter do you? Makes no sense. You still have the same weight bullet, but now it has more surface area to drag down the barrel. The same powder charge, no improvement there. And you have expended a severe amount of energy to size the bullet down. I don't see any feasible way this could accomplish any thing desirable. Am I missing some thing?   KN

[jrcanoe]

KN
Extruder barrels create more pressure. There has not been much fuss about them in the USA, but apparently they have been used with good success in Australia.

[Con]

Jrcanoe,
I think that Arthur Langsford had pressure issues with his 17 Myra Extruder, not sure whether he ever worked it out either. I believe at one point he approached Ruger seeking to use the 10/22 and 77/22 actions for his Extruders. Getting info on the Extruders is difficult since Langsford's death there has been very few people around to ask. I believe that Sprinter barrels in Sth Australia still may have some Extruder barrels in stock.
Cheers...
Con

[longgun]

Back when most of us were useing shooters.com  there was a lot of discussion about the 17 swager.   Can't remember for sure but a fellow with the first name of "Randy" was doing lots of conversions around the ruger 10/22 conversions to 17 cal.   He was getting velocity with hyper velocity  stuff like zappers and stingers with velocity around 1700 f/s. out of the 10/22's.   I had my barrel made for 20 cal but had an 8" twist, whick I found to be too fast.  Also I didn't specify that I needed a rimfire barrel so I may have gotten a barrel for jacketed bullets.   I have several 22 cal rifles with twist from 17" down to 14" twist.   And cronographing them the slower twist had more velocity and the more twist decreased velocith porportionately with the same ammo.

Swagging the bullets should increase the velocity, because of increase pressure vs lower voluum of the barrel.  Once the bullet has taken the rifling the pressure spike will be reduced.

If I try to do the swager again with 20 cal barrel ,  I think that I will use 14" twist and remove the riflings after about 14" of barrel.  Shortening the barrel should also increase the velocity.   IMO .........Don

[gunnut69]

Increasing the pressure in a rimfire is a dangerous practice.  While the rifle will handle the pressure I had suggested you check the gas handling properties of the action...  Where does the gas go when a case ruptures.  You are asking a case that's thin enough to allow a firing pin to detonate the priming misture by crushing the rim to contain over 10-12 thousand PSI.  It must also stabilize a bullet more than twice the weight the rifling was designed for.  Plus your going to create the bullet in the bore at firing.  That process will surely introduce a multitude of variables that should eliminate any chance at a usable level of accuracy..  Good luck but please be carefull...

[jrcanoe]

Gunnut69 If I do this I will be very carefull. I am just in the research phase right now. The mach2 barrels won't be out untill sept. and it will take even longer for their price to drop.  I own a long string, pully and brick house. Pieces of paper will tell the tale if I'm geting any blow back. Gas should come out the empty mag well and hopefully not thru the bolt down along the firing pin. If I get case ruptures I'll just rechamber and end up with a long throated 17hmr barrel. Thanks for your concern over my safety and more importantly any others reading this thread. Any and all gun modifications should be assumed to be dangerous untill proved otherwise.

[gunnut69]

Amen to that.  I've been working on guns for over thirty years and even being careful bad things can happen.  guess I've gotten pretty shy in my retirement years.  My last adventure was a 40 S&W.  Brought in because it wouldn't feed.  It had been over throated by some other ameture smith and while I noted  the problem I let it ride.  With a 45 ACP there would not have been an issue but I forgot about the 40 running at higher pressures.  It took several shots(had a nice group going) but a case finally let go.  Didn't hurt the gun much(bowed the steel reiinforced rubber grips) but the shock to my hand took over a month to heal..  Check the firing pin position and remember cas will travel along side the bolt unless there's a barrier. Eyes are not replaceable.  Wear safety gear... and good luck!

[rodgervich]

A friend of mine has made a .17 swager barrel for his 10/22. It shoots fine, not better or worse than regular 22lr. The bullets come out almost an inch long and they are neat to look at but it's really just a novelty.
Concerns over the gas blowing out into your face are VERY REAL! He has had a couple of cases blow out and the gas shoots out all around the reciever and out the bottom of the magazine. He got a faceful of hot gas and powder, he doesn't wear shooting glasses and was lucky he had his left eye closed while shooting with a 'scope or he would have been in BIG trouble.
If you really want to make a swager I would seriously recommend a bolt action rather than a semiauto. They work and they are neat but not any real gains over the standard 22lr parent. Wear shooting glasses EVERY TIME you shoot it!