Time for a new bbl- expanded

[sjk]

Installing inserted chambers, a little elaboration. Years ago when I was still smithing back in the 60's, I had a person bring in the most beautiful Shuetzen that I had seen. The problem was that it had a bulged chamber. Being a little new at the time I let it sit. Some time later I bumped into Parker Ackley and if I remember, at Perry. He recommended a fellow in Idaho by the name of Starr who would "rechamber the chamber" or re-insert it so I sent it out to him. Well, he did the nicest job and I couldn't even tell that this type of work was done to it. It shot like a dream and put them all in there. I said to myself, heck I'm a modelmaker, there's nothing here that I can't do. It was very difficult to set up the next pc that came in on a lathe due to runout, so I hung in over the side on my Bridgeport, fixtured it and then indicated it in. The chamber had a few .001's runout to the bore so I indicated in on the bore itself and then went ahead what this guy Starr did. I made up a straight hardened pin to fit the bore and indicated it in this way on the ZZ and indicating it to OC. In the years that I was in the business I'd say I did over 30 this way using the fixture for holding them vertically and boring everything out OC. I never had any of them come back and I didn't have to set the bbl back which was mostly the case. Setting the bbl back on some was almost impossible and cosmetically it would look bad. In the case of a drilling it was impossible to set back the bbl and still retain all the settings. Maybe someone out there will run into the same problem that I had and this may help them along a little. It sure beats a cheap way to save a bbl when the chamber/throat is shot but the bore is still in good shape. LOL

 

[TRECustom]

sjk, do you shrink fit the new chamber slug, or silver braze it in? I screwed up my T/C Contender .22lr chamber with a .22 Wmr reamer and am deciding whether to slug it or just open it up to .22 Hornet. I would like to keep it a Wmr and shrink fitting seems to me to be a better choice.

Thanks, Tom

 

[sjk]

Tom,
One of the first ones that I did was on a Holland and Holland in .300 that had a blown out throat and elliptical chamber. I shrunk in the insert .0015 and in about 10 rounds I noticed the bolt closed really hard. To make a long story short, the shrink didn't hold, but this is not necessarily true on a smaller chamber. The outward pressure on the walls should hold it in, I thought. With this in mind I never shrank any of them after that and went to a low temp silver solder which worked fine. Not one came loose after that. Again,the shrinking may be successful on smaller cartridges, but I never went that way so I can't relate to it. One thing I did do though, was to thoroughly tin the OD of the insert to make sure I got all of the surface to flow and mic'd the OD of the insert to a minus .0005 of the bbl. It flowed in nicely just like tinning a bore insert. One trick I did learn from all of this was to chamber the insert to about 50-75% completion using step drills before soldering it in. I didn't use that much heat to get it stuck in place. Later on I got a little more proficient at it and made up the whole inserted chamber on a lathe and then just soldered it in place and it came out fine. I had a rule to always work to a -.005 as a fudge factor just in case I screwed up somewhere and would have a problem with headspace. You can do this by mic'ing all the dimensions that you need before you start, and STICK to them. A journeyman machinist can do this procedure with no problem. For me it worked fine from a .450 Waats down to a to a .219 Donaldson
Hope it helped LOL
John

 

[TRECustom]

Nothing like experience, particularly when it works. I really appreciate the help. Maybe I can return the favor sometime.

Thanks, Tom