742 Barrel

[redfox33]

My Dad had picked up a 742 in .280 from a guy at work.  He knew something was wrong with it 'cause the guy was almost giving it away.  I took the gun to a respected gunsmith and he said the barrel wasn't any good.  He said the only thing that will solve the problem is a different barrel.  The gun is great shape other than that.

I've looked but the only thing I have found is .30-'06 barrels.  The gunsmith told me that in theory when these guns were made you could switch out the barrels if needed.  For instance the long-actions in .270, .280 and .30-'06 are all interchangeable.  He didn't know if special tools were needed for fitting though.  Is this true???

[gunnut69]

I've only worked with a few in this regard and they were interchangeable. That is NOT to imply that all are. The smith should check to be certain the headsapce is right. I wonder what is wrong with the barrel that's in the rifle.. ?

[redfox33]

It will try to eject the spent casing but it won't come out.  It will pull the lip off the brass but the casing will still be snug in the barrel after firing so it isn't the ejector.  He said a couple of things one - it could be major pitting or two - he said the barrels were made too thin and it could have been fired until it got hot enough that when it cooled it shrunk the diameter, I never heard of that happening before.  He kept it for over a month working on it, complete tear down and numerous polishes and other things to the barrel but the casing would still stick.

[gunnut69]

Pulling the lip off the case sounds like a problem with the chamber sure enough.. That amounts to a stuck case. I've never heard of a chamber 'shrinking' from getting too hot?? Egg shaped from over polishing,,maybe. or pitted badly..  I've even seen bad chambers from the factory.. When the case is removed are there any shiney spots on the sides or neck? The remington autoloaders don't sell well around here. There've been just too many problems.. Both with QC and premature wear.. I've 2 in the shop now that have the cam slots in the boltheads worn out. One's a really nice looking 243.. I don't believe I'd stick a lot of money in a 742..  Just my opinion of course..

[Nobade]

You might call Remington and see what they'd charge you to fix it. But as Gunnut says, they're not the best design anyway. I'll install muzzle brakes on them but beyond that won't have anything to do with them.

[redfox33]

When pulled out the case would have a rusty colored oily film on it.  Some areas darker than others.  I didn't notice any shiney spots on the case.  I may give Remington a call but with it being an older gun and them not producing parts for them anymore I don't really know what they can do.

[gunnut69]

They may have parts but I'd be sure to call first. Can't hurt to try though.. The rusty colored film does seem to indicate a rusty chamber.. If that's the case that may be the problem. Autoloaders can't deal with rust in the chambers. The brass cases bond with the walls of the chamber and won't turn loose.. The autoloader has enough power in the gas system to rip the extractor thru the rim and you've a problem. Before doing much try using a piece of fine (0000) steel wool wrapped around a mandrel(cleaning brush on rod or just a length of dowel) and chuched in a drill motor. Spin this fairly fast and use it to polish the chamber. The steel wool's action can ve enhanced by applying a bit of WD40.. Be sure to clean the oil and residue from the chamber several times and really good at the end. This should remove all the rust and leave the chamber nice and shiny.

[redfox33]

The gunsmith here did exactly that and the cases were still sticking.  He also said it looked like somebody else had tried to do the same thing and scratched the inside of the barrel up a little.

[gunnut69]

There's no good repair for a damaged chamber. If it were a bolt gun one could remove the barrel and set it back a thread, but the gas operated auto may object. Looks like a new barrel is the only way to go.. or sell the gun off for parts..  I did hear of a guy who rebarreled a 742 but didn't redrill the gas tap. Turned the rifle into a straught pull bolt action.. I've not seen it though.  Still it should work OK.. I think I would put an easier to operate bolt handle in place though..