Movement of reamer in chamber and die

[Phys86]

Is it common or a really bad sign if you have a chamber and a die where if you put the associated reamer into the chamber or die which they've cut and there is enough play to wiggle the reamer shank?

I'm not talking a lot of wiggle... Just the tiniest bit that would be detectable by hand. I would expect that it would be totally tight and not wiggle at all.

 

[boltfluter]

Is it common or a really bad sign if you have a chamber and a die where if you put the associated reamer into the chamber or die which they've cut and there is enough play to wiggle the reamer shank?

I'm not talking a lot of wiggle... Just the tiniest bit that would be detectable by hand. I would expect that it would be totally tight and not wiggle at all.

Sounds like the back of the chamber is over size. It is very easy to turn a reamer into a boring bar! Never a good thing. How are you holding the reamer when chambering a barrel?
Paul

 

[marazzi59]

In my mind a few .001's of wiggle is fine. As long as your not pushing your reamer all the way in to where it is hard to remove because without rotation it's stuck because it didn't cut but jammed. And if jammed it could and probably will screw up the chamber and reamer.

 

[Phys86]

Sounds like the back of the chamber is over size. It is very easy to turn a reamer into a boring bar! Never a good thing. How are you holding the reamer when chambering a barrel?
Paul

I didn't chamber it or cut the die, But I own the reamer set. I had brass sizing issues with that cartridge and Manson checked out the reamers for me, measured them, and verified that they are in spec. The conclusion they came to was that my chamber and die must be cut oversize a little bit by way of the reamer not being lined up properly and it acting as a boring bar as you suggest.. That seems to be the case since I can wiggle the reamer in the chamber and the dye a little bit.... Or the Smith polished the chamber and the die way too much, although I don't think the latter is the case because they both look a bit rough under the scope.

I was just wondering how common it is for that to happen for a decent gunsmith

 

[Phys86]

In my mind a few .001's of wiggle is fine. As long as your not pushing your reamer all the way in to where it is hard to remove because without rotation it's stuck because it didn't cut but jammed. And if jammed it could and probably will screw up the chamber and reamer.

I just slid the reamers in by hand to check fit

 

[Alex Wheeler]

After you cut a chamber the reamer should be quite snug in the chamber.

 

[LVLAaron]

Is it common

Yes

really bad sign

Yes


I did an FTR barrel for someone. Customer supplied reamer that's always worked. Phone rang, trouble extracting all brands of brass. Had him get me his print... 200 line was something like .4701 (way too tight) - Had to chase it with another reamer I have. His former guy always cut lumpy and oversized chambers, so the tight reamer wasn't a problem... until it was used correctly. We both learned something from that encounter.

 

[Phys86]

Yes

Yes


I did an FTR barrel for someone. Customer supplied reamer that's always worked. Phone rang, trouble extracting all brands of brass. Had him get me his print... 200 line was something like .4701 (way too tight) - Had to chase it with another reamer I have. His former guy always cut lumpy and oversized chambers, so the tight reamer wasn't a problem... until it was used correctly. We both learned something from that encounter.

Ahh that's interesting.

Considering I have the issue with both my chamber and die... I figured I'd need to fix both issues rather than one because it would either cause sticky extractions or potentially oversizing brass and early case life failure

 

[LVLAaron]

Ahh that's interesting.

Considering I have the issue with both my chamber and die... I figured I'd need to fix both issues rather than one because it would either cause sticky extractions or potentially oversizing brass and early case life failure

You and my guy have the opposite problem. His chambers were always oversized. I cut him one onsize, and he found out his reamer was too tight.

But.. depending how bad yours is, could certainly cause problems too.

 

[gunsandgunsmithing]

I'm wondering, within reason of course, how does a big chamber create extraction problems. Oversizing, I get but again, within reason. How much constitutes oversizing? If both the die and the chamber are equally over reamer spec, do we not have the same amount of sizing? IME, way more problems are created by a chamber that is too tight than too loose. Again, within reason. But that gets into incorrect spec'ing of the reamer, often happens when based on virgin brass dimensions

 

[Walt Krafft]

If it is a seating die, should not be a problem. You can not make a sizing die with the same reamer you cut the chamber with.

 

[Phys86]

I'm wondering, within reason of course, how does a big chamber create extraction problems. Oversizing, I get but again, within reason. How much constitutes oversizing? If both the die and the chamber are equally over reamer spec, do we not have the same amount of sizing? IME, way more problems are created by a chamber that is too tight than too loose. Again, within reason. But that gets into incorrect spec'ing of the reamer, often happens when based on Virginia brass dimensions

Sizing die was cut too big, more than the chamber I guess so brass wasn't sizing down enough. However, chamber was also cut big.

In reply to Aaron I was talking about fixing one issue or the other. Fix the die, then oversizing may occur. Fix the chamber, then my die definitely won't size brass enough.

 

[Phys86]

If it is a seating die, should not be a problem. You can not make a sizing die with the same reamer you cut the chamber with.

It's a sizing die cut with resize reamer.

 

[LVLAaron]

Is it a common cartridge you could get a cheap resizer for, just to see if it helps/works? otherwise... I'd say "fix everything"

 

[gunsandgunsmithing]

Sizing die was cut too big, more than the chamber I guess so brass wasn't sizing down enough. However, chamber was also cut big.

In reply to Aaron I was talking about fixing one issue or the other. Fix the die, then oversizing may occur. Fix the chamber, then my die definitely won't size brass enough.

If both are actually as big as you make it sound, it's obviously time to talk to the man that did the work. My issue comes from the amount of subjectivity with words like "feel". There is no such thing as perfect and a 1.000 inch peg does NOT fit a 1.000 hole, so there is always clearance. I'd feel better about giving any advice aside from talking to your smith if you were able to quantify some numbers. We expect perfection like it was common but it does not exist. There are lots of degrees of F***ed up though. I'd take or ship it to your smith and let him know the perceived issue and go from there. Frankly, we talk about 2 tenths this and that on this site but I challenge anyone with a lathe that still has the paperwork to produce the inspection sheet that came with the machine when brand spanking new, and post the spindle runout numbers on here. It takes a pretty good machine to produce sub .0002 runout numbers(not talking about anyone's half million dollar cnc machine but typical lathes used in gunsmithing every day) when new. Yes, setup could be the problem(twice) so it's certainly possible but we simply don't know yet...Just my 2 cents is all. It tickles me to see videos of an indicator at the back of a chamber with the needle not moving, like it proves something. Yes, it proves the hole is round but that's all.

 

[Phys86]

Is it a common cartridge you could get a cheap resizer for, just to see if it helps/works? otherwise... I'd say "fix everything"

30-284AI. So unfortunately, no. I've got the reamers for sale right now as was planning on getting out of it. But was just wondering about that "wiggle" I could feel.

If no one's buys them, I'll set it aside and have it ground to standard 30-284 in the future or get the chamber fixed and a new die made.

 

[Phys86]

If both are actually as big as you make it sound, it's obviously time to talk to the man that did the work. My issue comes from the amount of subjectivity with words like "feel". There is no such thing as perfect and a 1.000 inch peg does NOT fit a 1.000 hole, so there is always clearance. I'd feel better about giving any advice aside from talking to your smith if you were able to quantify some numbers. We expect perfection like it was common but it does not exist. There are lots of degrees of F***ed up though. I'd take or ship it to your smith and let him know the perceived issue and go from there. Frankly, we talk about 2 tenths this and that on this site but I challenge anyone with a lathe that still has the paperwork to produce the inspection sheet that came with the machine when brand spanking new, and post the spindle runout numbers on here. It takes a pretty good machine to produce sub .0002 runout numbers(not talking about anyone's half million dollar cnc machine but typical lathes used in gunsmithing every day) when new. Yes, setup could be the problem(twice) so it's certainly possible but we simply don't know yet...Just my 2 cents is all. It tickles me to see videos of an indicator at the back of a chamber with the needle not moving, like it proves something. Yes, it proves the hole is round but that's all.

Unfortunately, he is no longer in business and I can't contact him. So without doing a cast of the die and chamber and measuring with a mic, I just won't know for sure. I don't have a mic and haven't done a cast.

Ray at Manson measured my reamers and verified they were spot on to spec. He also had the sizing die and noticed there was some wiggle when fitting the reamer in. That as well as measurements on brass he took and all the other information I gave him on loads, his best guess was that the reamers weren't aligned and acted as a boring bar.

I can say with certainty that my chamber reamer is specd to 0.502 at the 0.200 line and measured somewhere around 0.5025. My brass was coming out of my chamber after multiple firings with the largest diameter being 0.503 (or 0.5035 can't remember) just forward of the 0.200 line. Sizing die wouldn't size it down any further than 0.5025 even though the 0.200 line on my resize reamer was 0.4985.

This is with Peterson brass that measures 0.499 at base.

 

[Walt Krafft]

Your chamber dimensions and fired brass dimensions sound fine. You may just need a new sizer made. Find a new smith, explain the whole situation, and have him cut a new sizing die using the resize reamer. Sizing dies need to be heat treated and polished after cutting, this could have created the issue.

 

[DShortt]

Threads like this make my head hurt. There's been a lot accomplished my just throwing stuff on the wall and seeing what sticks. Never seems to be the same answer every time.

Many will take exception to those observations and that's fine. If I had it all figured out I'd explain it in detail.

 

[Lucky Shooter]

Maybe somebody who knows his stuff will chime in and
talk about taper boring.

A. Weldy