Poped My Chambering Cherry, Now Have A Question

[tinkerfive]

Ok I thought I was going slow enough.

cleaned and checked with GO guage 4 times, and no bolt closure.

On 5th time bolt closed and end play noted with bolt closed.

Checked with NO GO.

$^^%^$%*^%* IT!!!!

The bolt closed on the NO GO.

So back to the lathe and cut the shoulders back.

This time 3rd time was the charm.

Bolt closed on GO guage with no end play and

did NOT close on the NO GO.

 

 

I finish reamed this chamber twice and

the rear 3/4 of the reamer cut nary a trace of

metal.

 

So now here is the question...

Is this unusual for only the front of the reamer to cut ?

I would have thought as the reamer moved forward in

the chamber all surfaces of the reamer would have cut

evenly. The only conclusion I can come to it that A&B

rough chambered the barrel to a larger diameter than

the finish reamer. Is this unusual or any concern?

 

I didn't think to measure before I mounted the barrel.

 

[724wd]

i think it depends on caliber.... don't some cases have less taper than others? perhaps someone with actual experience might chime in... my cherry is firmly intact! :-)

[Doble Troble]

Welcome to chambering!

 

The shoulder of the reamer is definitly going to take off more material toward the end than the body of the reamer. Its also very possible that your reamer is on the thin side of tolerances while the A&B reamer was on the large side. I wouldn't worry about it as long as headspace checks-out. We've all been there having to take a bit more off the shoulder, so you should feel good about not being left out of the experience.

 

If you're chambering for accuracy you should consider your first loads to be fire forming, and then adjust your die to neck size only. Hopefully your chamber isn't so big that this results in sizing of the case walls too. If this does turn-out to be the case, don't worry, just get yourself a collet neck sizing die (cheap from Lee) and your problem is solved.

For hunting accuracy you should be fine with the FL sizer, for target loads neck size and everything's good.

 

Congrats on your first chamber! More details are in order, cartridge, action, etc...

 

I am obsessive about checking the quality of reamer cutting with a flashlight - I think this comes from a history of using crappy (home made) reamers (not all are crappy, but a few have been, and its hard to predict in advance how well a home made job is going to cut). Make sure your chamber is smooth and shiny, if its not some emery paper can help (but will increase the the chamber a hair - but if it prevents unsightly ridges on your cases [that can create extraction problems] its a good thing). The other thing to think about before taking the barrel out of the lathe is to put a bit of chamfer on the mouth of the chamber. If you cut it good and clean the edge will be sharp and will happily cut into cases during chambering - either shaving brass or preventing chambering. I do this with a lathe tool at ~ 45*, but others use a counter sink. Just a hair of a cut is all that's needed.

 

 

Congrats again!

[Guest Uncle Pope Redman]

Chambers are like any other tool, they vary.

The tool suppliers claim that their reamers are within SAAMI specs...some are-some ain't, without some pretty sophisticated measuring equipment, the only way to tell is to actually cut a chamber. I have new reamers and I have old reamers, I have reamers that have been sharpened a few times.......they will all cut a good chamber, but the chamber may not be spot on to SAAMI specs.....it doesnt have to be, to shoot well.

Your reamer may not cut the same as the factory reamer, it would be a near miracle if it did.....that factory reamer has cut thousands of chambers, while yours....?

When you fire your rifle the first time, examine the case carefully, you do not want to see a line around the case where the factory reamer transitioned to your reamer....that is a No-No.......you will then need to remove the barrel and set it back to where only YOUR reamer makes the cut. Reaming a chamber is not the mystical expierience some make it out to be. You only have to keep the reamer clean of chips, turn no more than a quarter of and inch of metal out of the cahmber before pulling back and cleaning the reamer and the chamber, also ...UNDER NO CIRCUMSTANCES REVERSE THE REAMER! that is the big UH-OH! you will leave a nasty jagged cut in the chamber wall that will most likely ruin the barrel. Once you have gotten your chamber cut to gage, you may wish to chuck and old barrel brush in a variable speed drill, wrap some four "O" (0000) steel wool around the brush and slowly turn it into the chamber. This burnishes the chamber walls and helps keep brass from siezing or dragging in the extraction process.

You will read and hear many different methods for getting a good chamber on a rifle, some will get so complex with formulas and theorums and quotes from Pythagoros to Kuhnhausen......they are all correct...and they are all wrong.......depending on who you talk to, the best method is the method that works best for you........

Good Luck and good shooting!

 

Uncle Pope Redman