Rimfire Chamber boring

[escopeta]

Have a Rim-x with Shilen #5 ratchet and Ezell PD tuner that shoots quite well with the JGS match chamber and Midas, but want to experiment with chamber boring. I have a new M24 profile Shilen blank on the way that I plan to use for testing.
I have test bored a piece of rim-fire barrel with a tool I made and seems to be no problem. Any opinions or advice regarding this project? Have good lathe with spiders fore and aft and precision measuring equipment.

 

[1Merlin]

Sounds like a great idea if you can afford to mess up (nothing negative meant) while learning/experimenting. I know there are lots of well thought out reamers already out there. Unless you plan something really out of the ordinary it's probably already available.

 

[escopeta]

Already have available all the good reamers available. Just want to experiment and the barrel on the way is just for that. Project I wanted to do.

 

[Tony K Harper]

Already have available all the good reamers available. Just want to experiment and the barrel on the way is just for that. Project I wanted to do.

Many rimfire gunsmiths prefer to bore their chambers. If you feel OK about cutting the leade go for it.

Some smiths bore the chamber but then use a reamer for the leade.

Please take pics and share when you get started.

TKH

 

[flatlander]

There was a discussion on Jerry Stiller's RimfireAccuracy site where he discussed boring 22RF chambers vs. reaming them. The jist of what I got out of reading the thread a couple of times is that boring had some theoretical advantages, but after he'd invested quite a bit of time & money in trying to get around issues involved, he more-or-less (at this point in time at least) threw in the towel. I'm still wet behind the ears when it comes to 22RF work; it often strains the limits of my puny knowledge & experience to get a really good job done using a very good quality match reamer. I'll leave it to others who know better what they're trying to accomplish to experiment with boring. One thing though - as hard as it is to get new Shilen blanks right now, I think that if I were going to experiment with something like you're contemplating, I'd get a few take-off Anschutz bbls and experiment with them first...

 

[JohnW...ski]

One of the first rifles I built from scratch, an FDH#2 falling block, was a .22 RF, I was too cheap to buy a reamer and bored the chamber with no problems. FYI, Bill Calfee advocates using a reamer that is straight not tapered and he builds some seriously accurate rimfire rifles.
John

 

[escopeta]

I like to experiment and this barrel is much longer than I use so I can screw up a few times and still be okay against my standard. Know Rimfire is ammo dependent as opposed to center fire where you can tune your load to rifle. Looks like Rimfire is tune your rifle to the load and not so easy. Just have to play with it.

 

[JohnW...ski]

I like to experiment and this barrel is much longer than I use so I can screw up a few times and still be okay against my standard. Know Rimfire is ammo dependent as opposed to center fire where you can tune your load to rifle. Looks like Rimfire is tune your rifle to the load and not so easy. Just have to play with it.

If you are planning to go down the road of building rimfire rifles read Bill Calfee's book The Art of Rimfire Accuracy. There is a lot of information in the book with his unique way of looking at some problems.

 

[JMA]

I believe Jerry Stiller was boring them on a cnc lathe
That gives much better control of feed rates and angles with no dwell time at at end of cut.
It would be very hard to duplicate the results on a manual lathe.

 

[escopeta]

Got Shilen M24 contour barrel done with h .225” chamber diameter and went with the Savage barrel nut arrangement to set headspace easily. Starting with full bullet engraving. Have extra adjustment so I can play with engraving. It does load, fire, and eject without bullet damage from the magazine. Bullet is all the way in the rifling. Will see how it goes when I get chance to shoot. For Midas only. MPA chassis, IOR Valdada 36 br scope shooting off SEB NEO. Fun gun for me.

 

[BP1]

Got Shilen M24 contour barrel done with h .225” chamber diameter and went with the Savage barrel nut arrangement to set headspace easily. Starting with full bullet engraving. Have extra adjustment so I can play with engraving. It does load, fire, and eject without bullet damage from the magazine. Bullet is all the way in the rifling. Will see how it goes when I get chance to shoot. For Midas only. MPA chassis, IOR Valdada 36 br scope shooting off SEB NEO. Fun gun for me.

Glad to see it working out for ya.

 

[linebaugh]

Not meant to be negative but I have to ask why the bbl nut? Are you planning to play with seating depth?
Second question, what did you do on leade angle?
Last question. Are you mag feeding and how rough is the actual chambering process with full engagement? EDIT... yes you are mag feeding, no other way. I guess I meant more along the lines are you benchrest style or PRS type use.

I have done a few rimX barrels now and my reamer has .0007 taper and I have it set up for rifling engagement of the first band only on ctrX. My idea was to keep the action as smooth as reasonable as I use it for PRS/NRL type shooting. Just curious how much you feel it as I am considering having a second reamer cut.

Can't wait to hear how it shoots.

 

[escopeta]

I used a straight fluted chucking reamer with a 45 deg. cutting angle on lead end. A standard type reamer. No tapered lead and straight wall. For depth I went in length of cartridge case plus about .015”. Runout after reaming was only about .0002”. Started with full bullet insertion now and can always go in deeper for less engraving. No difficulty in chambering feeding from magazine but in dirty environment you could have more resistance. I don’t shoot like that and only bench so no issues.

 

[escopeta]

First shoot today with barrel using Midas and a comparison with some Pistol Match. 10 rounds@50 yds. light cross wind. Fired about 75 rounds and rifle was consistent, shooter not but looks promising with no tuner. Only took a couple of hours from a cold start to do the barrel. Not pictured but I shot at 100 for grins with 10 rounds in under 3/4”. No issues with chambering or extraction. Barrel is just over 26”.

 

[linebaugh]

Results have promise. Thought you were actually boring a chamber not reaming. Keep posting. Interesting

 

[escopeta]

Took barrel off as waiting for Ezell tuner and going to cut it back to same length as my lighter weight #5 Shilen RF barrel with JGS match chamber that is from Lee Gardner. Ezell tuner works well on that barrel.

 

[RGRobinett]

Took barrel off as waiting for Ezell tuner and going to cut it back to same length as my lighter weight #5 Shilen RF barrel with JGS match chamber that is from Lee Gardner. Ezell tuner works well on that barrel.

This is a very interesting thread! Just to be certain that I am following corectly: the barrel will be shortened at the muzzle end, tuner installed, and the chamber left as/is (cut via chucking reamer)?RG

 

[holstil]

When you say bore, I’m thinking single point as opposed to reaming?? I played with single pointing a few chambers. When I did my first rimfire, didn’t take me long to order a JGS match reamer. Tooling flex and figuring out how much meat for final cut got the better of me. I never felt completely confident I could repeat it as well as a reamer anyway. I do not have a cnc.
Curious.

 

[escopeta]

No problem boring. I cut my own tool and I have precision bore measuring tools. I want to compare with JGS MATCH chambered barrel I have. Nice thing about RimX action is cartridge rim is captured in the bolt head so removal of chambered cartridge is no problem. The claw type like my Anschutz would probably not pull out a chambered round from my chamber.

 

[skeetlee]

Dwell will be a problem with any or all manual machines. I wouldn’t even attempt it with a manual lathe unless you just want too
I build several rimfire rifles in my shop and I use a JGS match reamer for a large percentage of my projects. My mentor uses the same reamer and had several top 10 rifles last year at the ARA nationals. Cutting a good chamber is only half the equation. Polishing leads and the throat is also extremely important.
I do think with the proper machine and tooling boring a chamber single point can be very effective. Certainly not a novice technique. Give it a whirl though if you must. Nothing ventured nothing gained!