Just for kicks, and pending on the delivery of the long promised Remington Spartan Double rifles, what affects will the chrome lined barrels have on a chamber reamer if one was going to rechamber one of the 45-70? Any special care needed to rechamber a chrome lined bbl.?

I tried that once on a Browning BLR I was trying to set the barrel back. I couldn't figure out why the reamer was "sliding" in the chamber and even used two different reamers. Then the "light dawned" and I figured out that it had a chrome plated bore and chamber. I took 80 grit enery cloth and roughed the chrome out of the chamber as much as possible and then tried re-chambereing. It kind of hesitated, skipped and caught and finally re-cut the chamber. With a double barrel, you'll have double the "fun"! You'll have to be careful and use a split dowell in a drill motor to rough out the chrome in the chambers, being careful not to go in too deep. I don't envy you having to hand cut two chambers, assuming you want to turn it into a .45-90/.45-100/,45-120.

I forgot to mention that you could also get a carbide reamer and that would negate having to remove the chrome at all.

I thought about carbide also. How much do they run?

I don't know because they say "call". That usually means "a lot". Check their website out; http://www.pacifictoolandgauge.com/carbidereamers.asp

Jeffeoso started a string on the Big Bore board about doing a group buy of the Spartan double 45/70's.

If that goes through I wouldn't buy a reamer as one of the Big Bore gun cranks will probably do a group deal on rechambering and we can all split the cost of the reamer.

I've always been of the opinion that chrome lined bores were of the persuasion that would ruin a HSS reamer. Carbide would be the way to go with the warning that chrome has a tendancy to chip away when being machined.

I was tasked ream a Chrome lined bore. The customer insisted I use a combination of lubricants; carboxymethyl cellulose, sodium alginate and EDTA, and also a latex liner.

It all worked out well, and I the chamber seemed very smooth.

This is little bit off topic, but I once lenthened a forcing cone on a shot gun with a chrome bore and it was a BITCH, go carbide or anything beside a standard reamer. Hard chrome is just that!I'm sure a latex liner would help.Stepchild

It keeps contaminants from gettting in the reamer.

I just had an episode with a A&B shortcahambered Series 3 barrel from Midway. The brand new reamer from PT&G behaved as described . Would not cut. I tried the reamer in the old pitted barrel I had taken off and it cut like a hot knife through butter.
While looking in the chamber under a stronger light, I seen a black coating. Further inspection showed me the whole bore had a black matte coating too.
The man I talked to at Midway never heard of such a thing, and I've got anoather barrel coming.
Could it have been hard chrome, and if so how and why did it get there? Wayne

I think I should have asked if it could have been black chrome, anyway if it was, it was plenty hard enough. I couldn't touch it with a scriber, while ajacent bright steel marked easily. Wayne

Walex

PTG reamers are made from a differant alloy than other brands. They will not cut at speeds we are use to using, 45 to 55 rpm. You need to adjust your spindle speed up to 120 rpm. Makes all the differance in the world.

I was trying to hand-ream the short chambered barrel that is sold that way on purpose, so that you can finish ream the last 50 thousands or so with out a lathe.
Simple mehanics stuff.

I doubt that one would get up to 4 or 5 rpm and intermittandt at that, with a tee handle. As I said, the reamer cuts like a straight razor in the junker barrel I took off.

This surface is so hard I'm sure that you would just burn up the tool if you had it in a lathe. What flakes away is very hard and gritty, I'm sure it would knock chunks out of most cutting tool edges at increased speed, like cutting metal that had sand imbedded in it.

Got a phone message from the man at Midway USA saying it was caused by the hydraulic oil from the button rifling not being cleaned up. If so, how did the chamber get reamed and plated ? After the barrel was turned, cut to length, crowned, threaded, is when the short-chamber is cut, nobody noticed it was turning black and hard. Some oil would have to dribble out and black plate the outside too if that was the case.

I run 140 gallons a minute of hydraulic oil 20 hours a day to the deck machinery of my fishing boat when hauling seine all season, and never seen any of it turn the surface of any metal black and hard as a rock, so I don't think that explains it.

What ever, I would be worried more about what might happen I some one managed to grind though this and managed to gt one chambered and then fired it. Might be fine, might just be grabby or tight and blow the barrel up if the bullet stuck.

Wayne

Wayne,
did midway just try to tell you that the INSIDE of a barrel had millscale? LOL!!!!!

try what craftsman said.. 120-140 .... and tap majic

jeffe

Thanks Jeffe,
No, Just said that they didn't clean up the Hyd oil used when they button rifled barrel. What I was trying to get across is why would anything done is why would any thing done during the rifling process coat the surface of the chamber which is machined much later.

I would imagine that One could try a lot of things, but would you waste any time trying to make a defective product work. And a rifle barrel or any defective part in a gun might not be safe.

Other than having the vendor make it right, I guess my interest here is academic, curiostity as to what this black and hard surface is, and how and why did it get there.
Wayne

This just just a SWAG, and a half-SWAG at that, but could it hve been an oxide formed from a dull and too hot reamer forming an oxide and work hardening the chamber? I think that would be waaaay hot though!

No the entire bore and chamber was coated rifling and all, very uniformly, one end to the other. none of the ouside surfaces, they were shiny and bright , and entirely normal. Wayne

Are we sure that you had a button rifled barrel, or could it have been a hammer forged tube? Some HF barrels have the chambers formed by the same mandrel as the rifling (barrel comes out needing not much more than crowning & threading. Would that explain the "uniform hard surface layer" you experanced?

Tailgunner, Thanks for the input. That could very well be, the thought had ocurred to me, but the customer serviceguy at MidwayUSA said it was button rifled.

But whether he knew what he was talking about or was just throwing something out that he picked out of the air while he was looking into the problem, or a solution to the problem, who knows?
Wayne

If you ever have to use a solid carbide reamer be VERY CAREFUL!!! The 300 Win reamer [JGS] I have is so $%^^ sharp it`ll cut your hand just by picking it up wrong. Lord help you if you try to grab it if it starts to fall. Also it`ll shatter easily too. It will cut though.

Aloha, Mark

Midways techincal help is not much. They did a bait and switch with me last May. I sent a $900.00 order back and told them to take me off their mailing list. Integrity and character are of the utmost essential in the gun business. They make very little themselves and one can find about anything they sell somewhere else. I would rather buy from Dave kiff, Dave Manson, Brownells, etc., and pay retail than support Potterfield and his chronies.
Longshot

quote:

Originally posted by walex:


Got a phone message from the man at Midway USA saying it was caused by the hydraulic oil from the button rifling not being cleaned up.

I called Midway and asked a question about thier ".223 Remington reamers".
They referred me to Remington Arms.