Home Forums Hunting & Shooting Gunsmithing Threading, chambering LW-50 stainless?

What is the trick to threading and chambering a Lothar Walther LW-50 stainless barrel? Had a local guy do one in 7mm PRC (yeah, I know, should have used Shaen) and he had problems. He said he couldn't use his 8-stud spider chuck cause it wouldn't hold the barrel cause the LW-50 steel was so hard that the pressure he had to put on the carbide reamer to get it to cut caused the barrel to turn in the spider. He was using a brand new Kiff carbide reamer (is that the problem??? ;), but had difficulty getting a smooth finish until he switched from Sulphur based to Tool-X nano fluid. Said he couldn't cut the steel with a HSS parting tool without it going dull cause he said the LW-50 steel was too hard so he had to part it with a carbide parting tool (when he faced the breech). He also said he's not happy with the quality of the threads. Says they look a little rough. Maybe he doesn't know what he's doing? Not trying to be a critic. He was using a high-end Precision Matthews lathe. I pick the barrel and action up tomorrow to send off for nitriding and will post photos tomorrow (if'n I can figure out how). I'd like some candid opinions on the work and the problems discussed above. The next project is going to Shaen for sure (lesson learned).


TIA

There are many known issues involving machinimg LW50 barrels. That doesn't mean they're good or bad...just different.

The nuances for machining them have been widely available from not only LW but many other sources for at least a decade and a half.

We worked with them as late as 2007 on the Benchrest stuff..

Yeah, I gave my guy the LW info on chambering LW-50 and it didn't seem to help.

S.O.P. for LW.

In this day and age, I can't savvy intentionally choosing one. The last two I got were freebies and I passed on using them. They're still in the barrel rack.

I had a proof do that to me. I managed to get through it with hss.....but holy crap did I sweat. I turned around and cut two barts with that same reamer and they were like butter.

I understand your point of view. I like their product though. I've used them for many projects and like them. I like their precision and the quality of their steel. I also like their polygonal rifling which they have in some calibers. Of course, their value presupposes a machinist who can machine their steel cleanly! My .02 worth.

At one time LW had a mixture to use on their barrels on their website. Equal parts high sulfur cutting oil, MolyD and ATF. I did one barrel with it, didn't see where it made much difference. The chamber did OK, but thread finish and crown finish never looked good. That was the first and last.

And now the new, unfired, untested, unquantified barrel that the 'smith had issues doing is going off to be nitrided?????????

Admittedly. I'm not much of a gambler. That scenario gives me the heebie jeebies.

Yes. The issues I described above did not affect the chamber. It looks good and I'm confident it's straight. I've never had an LW barrel that didn't shoot tight groups. I intend to scope the throat before sending and may JB it and the bore, depending on what I see prior to nitriding. If it doesn't shoot, I'll let you know so you can have the last laugh.

I scoped the chamber and throat. They're a butchered mess. The threads are a torn and butchered mess. I've got to find someone to bush the tenon, recut the threads, set the barrel back and then rechamber. Meeting with the "smith" tomorrow to talk about a refund. $380 for a complete ruination of a $700.00 barrel---unless I can find someone to bush the tenon and do everything over again.

It's not a "last laugh" thing by any means.

I hope it turns out for you.

Thanks. It's a mess. Per Greg Tannel, I need to find someone with the skill to bush the tenon with a 40 TPI thread, torque the bushing on with some permanent type Loc-tite and then mate/thread the bushing to the action and then recut the chamber. I've only got an extra half inch of barrel to work with, but I think it is enough to recut the chamber. Greg is too busy. I'll find someone. Hitting up the butcher tomorrow morning for a full refund on his "gunsmithing".

I tried to talk myself into the acceptability of the work, but it's just terrible. Chatter marks everywhere on the breech face. Threads look like alligator skin....its a mess.

Honestly, even if the threads look bad...that's not always a sign that it won't shoot. When you examine the mechanics of 60 degree threads and how they actually work, it's a small percentage of the length of the threads that 'load' when torqued.

If the throat is in there straight and the chamber is decently dimensioned and doesn't have too fine of a finish, I'd shoot it and go from there.

I never had any real problems with the Lothar Walther barrels, but I confess to only fitting a few. Contrary to their claims, they were not particularly straight, which complicated set-up. The steel was tough and had tendency to work harden if you weren't careful when reaming. The throats had a feather edge on the lands, left by the reamer. For this reason, I lapped the throats. I never had any trouble with threading. I don't care much for the barrels and would not buy one for myself. I do have a CM barrel from LW (took it on trade) which looks OK and I'll probably use it eventually. GD

Thanks and I don't necessarily disagree with you. The load-bearing side of the threads is not as bad as the other side. The problem is it just looks terrible. There are a lot of chatter marks on the breech face and where the bolt nose inserts. I could never sell it like that, if I chose to. I'm gonna try to find someone who can bush the tenon and recur the threads and chamber.

I can't imagine anyone in their right state of mind that would touch it. If you could find someone, at $85/hr. (bargain rate) you'll have more in it after a mornings work than a new blank would cost.

The other option would be to cut a half-inch off the breech, rechamber, pick up the old gatored threads and cut another half inch of new thread forward of the old ones. That would still give me a 22" long barrel.

Contact Pete Pieper of Precision Barrelwork. Pete did quite a few of them for Blackstar (Deathstar" Barrels in the early days. They bought the LW50 barrels from LW and did their chemical process to the bore and rifling. I believe they are a PH steel. Best luck I had was sulferized oil and moly D with heavier speed and feed.
https://www.precisionbarrelwork.com/
Pete might kill me as he thought they were a piece of [bleep].

Thank you Butch. I'll leave your name out of it! Give you a little protection!

Thanks, I need a lot of help with this.