problems with match chamber

[#57]

While Im laid up, Im building a single shot rifle for my grandson. I started with a marlin reciver because it feeds from a tray instead of having to feed directly into the chamber. added a shortened Rem barrel. and wanted to cut a match chamber into it. I ordered an anshutz type reamer from midway. the reamer was sharp and cut very easily by hand.BUT, this is where the problem starts. the chamber is so tight that I have to forse the bolt to close, and the chamber mouth is so sharp that it catches the lead bullit and wont feed from the tray.

I want a rifle that will shoot but if its a pain to load it wont be much fun for a kid. what should I do from here? Ive thought of "slightly " chamfering the mouth of the chamber and polishing the chamber with a dowl and some lapping compound. or I could open it up to a sporting chamber. what do you guys think ? #57

[BlauBear]

What kind of ammunition? Closing the bolt on some ammunition in a match chamber is very hard, so you might want to use something appropriate to your favorite .22 ammo. As for the sharp chamber edge, you might want to try polishing the chamber with Flitz, a chamber mop and a power drill. I've seen several shooters successfully use this on sticky chambers, but it makes me cringe.

[#57]

The ammo was RWS target, and Eley. it leaves the cases evenly scraped all the way around, and from mouth to rim. Im thinking of trying a slight chamfer at the mouth only, and if that doesnt work recutting with a bentz type chamber reamer. I did not think it would be this tight. thanks #57

[BlauBear]

You're right - that shouldn't happen, and you're thought about the Bentz chamber is probably right on.

[Evelio Mc Donald]

#57
To replace the existing barrel, with a Rem. barrel, the shank would have to be remachine for it to fit and headspace correctly.
You said you bought a Anchutz reamer, (never heard of one) and cut the new chamber by hand, ( Not recomended ) I hope you actually turn it by hand, and not with a powered tool.
First try to close the bolt in an empty chamber, it should close easily with just a slight pressure to expand the extractors, if it does not, your headspace is not right, or the extractor grooves are not correct.
All the scratches in the fired cases indicates that you had shavings caught in the reamer when cutting the chamber. Trying to polish it by hand is impossible, it needs to be put in a lathe, and polish at high speed.
Trying to re-cut the chamber with a Bentz reamer designed for semi auto rifles will not help.
I would rather buy a set of go, no-go gages and check the headspace, this is the distance between the bolt face, and the chamber face. Do not bevel the mouth of the chamber, this will make the case expand out in that area when fired, and will push the extractors out enought to hinder the extraction function. The best would be to polish the face of the chamber with a fine piece of Emery cloth, and thumb pressure with a rotating motion.
Evelio.

[#57]

#57
To replace the existing barrel, with a Rem. barrel, the shank would have to be remachine for it to fit and headspace correctly.
You said you bought a Anchutz reamer, (never heard of one) and cut the new chamber by hand, ( Not recomended ) I hope you actually turn it by hand, and not with a powered tool.
First try to close the bolt in an empty chamber, it should close easily with just a slight pressure to expand the extractors, if it does not, your headspace is not right, or the extractor grooves are not correct.
All the scratches in the fired cases indicates that you had shavings caught in the reamer when cutting the chamber. Trying to polish it by hand is impossible, it needs to be put in a lathe, and polish at high speed.
Trying to re-cut the chamber with a Bentz reamer designed for semi auto rifles will not help.
I would rather buy a set of go, no-go gages and check the headspace, this is the distance between the bolt face, and the chamber face. Do not bevel the mouth of the chamber, this will make the case expand out in that area when fired, and will push the extractors out enought to hinder the extraction function. The best would be to polish the face of the chamber with a fine piece of Emery cloth, and thumb pressure with a rotating motion.
Evelio.

The shank was cut to match the old marlin stub, the extractor was also cut to match. [ one extractor]. the reamer was made by PTG to match the anschutz chamber. it was turned in by hand. with an empty chamber the bolt moves easily. the problem it seems to me is that the chamber is too tight. it drags evenly all the way around the case. and the mouth of the chamber is very sharp. it catches the bullit and wont let it feed from marlins tray as it used to. could it be that the reamer was made too tight? I have access to a set of head space guages but as hard to chamber as brass is I hesitate to put them in there. I can barely push in a case with finger pressure. so far Ive been working with brass cases that have had there bullits pulled. the old marlin chamber ,I can drop a case in and feel side movement. if I turn it down the case will drop free. with the new chamber it will not drop free and has to be pulled with force. this is the first chamber Ive tried and its not going well at all. how can I tell if its a tool problem or if its my improper use? I thank you for taking the time to help me. and if you can think of anything else I could do I would be so greatful. #57

[Boyd L.]

could it be that the reamer was made too tight? I have access to a set of head space guages but as hard to chamber as brass is I hesitate to put them in there. I can barely push in a case with finger pressure.

In my limited experience, headspace gauges are made with body diameter and taper to minimum dimensions to allow insertion into any properly cut chamber. In the unlikely event one did become "stuck", this wouldn't hurt the gauge, simply drop a rod from the muzzle to dislodge it and it would indicate that the chamber isn't correct, allowing you the opportunity to cut it off and redo the chamber cut. I personally wouldn't make any other moves until this step verified all the information I need about the chamber and headspace.

Trying to polish it by hand is impossible, it needs to be put in a lathe, and polish at high speed

I agree. This is the only way to ensure concentricity, which prevents any "angles" from being polished into the chamber/bore relationship.

Just one man's opinion. Your mileage may vary.

[Evelio Mc Donald]

#57
I would not do anything until you check the head space, if you did not go deep enought with the reamer it will make the chamber tight. PTG is in my opinion the best reamer maker.
Most of PTG 22 LR reamers actually have a stop buid in them which is the size of the ream of the case, it should be run in until it touches the face of the chamber. All go, no-go gauges fit real loose, actually all they do is check the space between the chamber, and the face of the bolt, they will not get stuck in the chamber.
Evelio.

[#57]

OK, I borrowed a set of guages. it closes on the go and wont quite close on the field or the no go. when I run the reamer into the chamber I stoped just as it touched the stop built into the reamer. I also used a very brite light and a magnifing glass to inspect my work. the very opening of the chamber has a jaged edge going most of the way around. but the rest of the chamber looks fairly smooth. I may be able to clean this up with very fine emery cloth as you said above by just sanding the face of the breech. Ill give that a try tomorow. thanks again for your time. #57

[Evelio Mc Donald]

#57
Well it looks like you done everything the correct way, after you polish the face of the chamber, and get rid of the jagged etch, just feed a live round in by hand, and try closing the bolt. If it is still real hard to close the bolt, you may want to go about .003 to .004 deeper with the reamer. A tight chamber is more important to accuracy than a tight head space, being able to close the bolt with the no-go gage will not be a deterent to accuracy.
Good luck
Evelio.

[#57]

Evelio, I got a reply back from PTG. they said that this reamer has a chamfer built into it. and that I should run it in till it just "kisses" the breech with the stop. this is how I thought I had done it, but now Im thinking that maybe my "Kisses" are lighter than they expected . I stopped when it just marked the breech face. I have a few barrel pieces that I can experiment with differant depths to see if Im just not deep enough. Im not seeing any chamfer at all. and then if need be Ill cut a little off the breech and set it back to get the headspace back where it should be. thank you again for your time and Ill let you know how my experiment turns out. #57

[#57]

I got it! after PTG coaching me, I sent the reamer back to them to check. they found that it had been mismarked and replaced it with a new one. I tried the new tool in one of the experimental pieces and found that it would chamber ammo with just the slightest finger pressure. now I need to make a short extention for the Tee handle [ so I can recut it in the action] and Im in buisness. thanks all for the support. #57

[#57]

Well I got it back together today! first couple of rounds wernt so impresive but after about 100rds it will now shoot into 5/8" at 50yds! I tried several differant target loads and some of the bulk stuff. it will chamber "most "easily. it seems to like CCI standard Vel. I put an old pad on it so an adult could shoot it more comfortably. after these pics I also added a Simmons scope to complete it. DR

[BlauBear]

Looks nice, and nice work! Frustrating to have problems, but always nice to find out it was the "other guy"... Wonder if it will continue to improve with use?

[Jetmugg]

Very nice looking rig there. What more can you tell us about that stock? (i.e. is it custom made, adapted from some other application, commercially available, etc.).

That's a great idea for a "kid's" rifle (whether the kid is 8 or 80).

SteveM.