Chambering by hand?

For many years (a long time ago) the armorers at Fort Benning, Quantico and Lackland AFB used a pull through reamer on the Match M1 rifles for their respective shooting teams. The process was cut the chamber short, fit the barrel to the receiver, install the pull through finish reamer, and cut the chamber until the bolt closed on the reamer. The reamer was turned at the muzzle with a t-handle and a long extension that attached to the reamer. I do not know if the bolt guns were done that way or not. NRA High Power Rifle Competition is very different from Bench Rest Competition the latter places much more emphasis on the equipment the former much more on the shooter. The tooling in .308 Winchester can still be purchased from several sources. The “Gas Guns” (AR 15 and variants) used today in High Power are chambered in the lathe like a bolt gun except that the barrel extension and bolt are used when setting the headspace and kept together until installed into the upper receiver with the bolt carrier. The slick Gunsmiths lay things out so as to drill the gas hole in the barrel so it is completely in a groove and not in or intersecting a land.

Nic.
 
For many years (a long time ago) the armorers at Fort Benning, Quantico and Lackland AFB used a pull through reamer on the Match M1 rifles for their respective shooting teams.
Click to expand...
My understanding of that is that theoretically, there is some distortion of the chamber when the barrel is installed on the action. By finishing the chamber after installation, that is removed.

Whether there is any practical basis for this I don't know. Certainly it hasn't hurt benchrest accuracy, or some of the "spare no time & expense" smiths would do this.
 
Charles E said:
My understanding of that is that theoretically, there is some distortion of the chamber when the barrel is installed on the action. By finishing the chamber after installation, that is removed.

Whether there is any practical basis for this I don't know. Certainly it hasn't hurt benchrest accuracy, or some of the "spare no time & expense" smiths would do this.
Click to expand...


I dont think this method would allow for proper bullet to bore axial/radial alignment in the leade area that we strive for in competitive BR, but it might be fine for open sight and hunting applications.

There is only one way to achieve competitive BR chambering alignment and that is in a lathe with an adjustable chuck................Don
 
Don, I wasn't clear . . . happens a lot. I think what they're proposing is to almost finish the chamber in the lathe, so you have as good as alignment as you care for, then fit the barrel & finish the last few thousandths reaming by hand, pulling from the muzzle. The reamer will of course follow what is already there, just like Jackie's reaming by hand after he's set up the chamber with a boring bar.

But no BR 'smith I know of finishes reaming after the barrel is torqued in the action, and I'd guess if it really had an advantage, somebody would. Most of us don't fit our barrels that tight, though I've seen it argued that anything over 50-ft pounds will distort a chamber finished before torquing the barrel -- argued, but far as I know, not proven for CF. I'm sure not going to lose any sleep over chambering "conventionally."
 
this is what i use and find i can chamber to with in .0005 and when i finish a run
i hit zero and can go straight back to it.:D

regards tasy_ted
 
Last edited by a moderator:
Great minds think alike..............:)

tailstockDRO-vi.jpg
 
I also agree with Dave

It's not about how quick you can shut down the spindle of a lathe. It's about controling the reamer depth with precision. When I get the reamer to depth, I let it dwell for a second or to until it relaxes anyway. You can control the depth of the reamer to the thousandth with the dial on the tail stock. Want it closer? Put a dial or digital indicator on the tail stock.

Now a quick question for Mike in Colorado. You mentioned engine assembly. Do you have a crankshaft balancer, or do you have cranks balanced by someone else? I know this isn't a benchrest question, so you can answer by emailing me at crankbalancer@yahoo.com.

Thanks, Michael
 
Last edited:
oneeyedmac said:
I spoke with a smith recently who was trained by an 80 yr old gunsmith who did things "old school", to use the current vernacular. He finish chambers all his barrels by hand and his mentor sometimes completely by hand. He says it really allows precision because he can stop his hand faster than he can stop his lathe. His results are pretty phenominal too, his guns shoot extremely well.
Click to expand...

New to gunsmithing. How long does it take to chamber by hand versus by tail stock feed?

Ed
 
I've reamed out a number of shotgun forcing cones by hand and that is a real chore- I can't image reaming an ENTIRE chamber by hand!!

My first chamber job I wasn't too careful and I ran the reamer in more than I should have at the end- probably about .040 on the last pass. The guy teaching me stopped me and told me that I probably went too deep:confused:

We stopped and checked it with the gage and voila- it was perfect- not a single extra pass. Bet that doesn't happen often on a first chamber!!!
 
dennisinaz said:
I've reamed out a number of shotgun forcing cones by hand and that is a real chore- I can't image reaming an ENTIRE chamber by hand!!
Click to expand...

I can't imagine why you would want to ream an entire chamber by hand. It's one thing to deepen it a few thousandths by hand, another to run a reamer into a barrel an inch or two by hand.
 
Even an imbecile will do it only once, read my post no."8"

Dave Short said:
HOURS VS. MONTHS

Does anyone actually chamber by hand, or know someone who does?

-Dave-:)
Click to expand...
,,,,,,,,,,,,,,,,,,,,,,,,

.450AI has only a "tiny" shoulder, if the shoulder was any bigger I still would be there today hand reamering.

Shoot better
Peter
 
I spoke with this fellow again and he is reaming the chamber on the lathe and finishing it by hand. He prefers to do it that way and his rifles shoot extremely well, so who am I to argue?
 
I occasionally finish out a chamber by hand as well especially when the bolt won't close on a go gage with the barrel tightened in the barrel vise. A couple of thousandths at the shoulder is pretty easy to get by turning by hand and as long as you push directly in at the base of the reamer, it will only show shavings cut at the shoulder of the reamer. Of course, it deepens the throat a little, but those piece are miniscule compared to what comes out at the shoulder.
 
I have done a couple .243 chambers in the last month.

The first one I got to with in .005" as always, and then finished with a long socket wrench extension on a T handle pushing on the reamer through the receiver.

I have always done it that way.

The second one, I decided that I had enough accuracy with my depth mike to do it all on the lathe.

It worked, and the bolt just felt the go gauge as it closed.

What does it all mean?
Next time I will be doing it all in the lathe again, and I hope it works as well.
 
Chamber by hand?? I just did 2 45-100 chambers in my M'bogo double rifle project, feeding the reamer in with the tailstock, turning by hand. Oil, insert, crank in tailstock, turn reamer 6-7 times, uncrank, blow out barrel, wipe reamer, reoil, repeat about 30 times....about one hour per chamber, and a case of tennis elbow. :eek:
 
chambering by hand

Guys, when I say I chamber by hand, that means all I do is use the reamer to establish the final .005 or so size shape, and depth of the chamber, AFTER I have single point bored the thing.
I agree with Peter, reaming an entire chamber by hand would not be on my list of things to do. I figure that the Ancient Egyptians probably did their Benchrest Chambers that way, only they had slaves to turn the handle........jackie
 
Mike Bryant said:
I occasionally finish out a chamber by hand as well especially when the bolt won't close on a go gage with the barrel tightened in the barrel vise. A couple of thousandths at the shoulder is pretty easy to get by turning by hand and as long as you push directly in at the base of the reamer, it will only show shavings cut at the shoulder of the reamer. Of course, it deepens the throat a little, but those piece are minuscule compared to what comes out at the shoulder.
Click to expand...

Mike you didn't mention it but I am sure you loosen your barrel vice if it is over the chamber area. Just a warning to those who want to try it... a barrel vice is capable of temporarily distorting the chamber dimensions when it is tightened ... a reamer won't go in the chamber without cutting an oval chamber...
 
You must log in or register to reply here.
Back
Top