Thoughts on Lothar Walther?

[Buck Fever]

I'm still waiting on my barrel but while I'm waiting I have been watching videos from Mark and Sam After Work and saw their linear bearing bipod mount.

I like the idea but it is expensive, the bearings look Chinese which is probably fine but I'm cheap so I found a surplus Swiss made linear bearing that was half the cost and can make two bipod mounts.

It's cheap enough to experiment with so that's what I'm going to do.

It will be Arca mount for the bipod, not picatinny so potentially more stable.

I also tried forming a case. It went fine. I did a 338 RUM Lee sizing die with an 8mm expander as the first step just to expand the neck, then the .338" expander to complete the expansion. Next I bumped the shoulder back with my body die but that left the shoulder to neck junction undersized so back to the Lee sizer, then I trimmed.

It looks good, certainly good enough to make a few break in loads and send the once fired brass to Lee for a collet neck size die.

I haven't started doing the sizing yet, I want to make sure I set my brass to the barrel headspace so my brass is moving as little as possible after I form the new neck.

The good part is that I know it should work pretty easily.

 

[Buck Fever]

Life got in my way for a while but I finally got the barrel.

So far it looks good but I haven't given it a really thorough inspection with my Teslong bore scope yet.

One thing was weird. I screwed it hand tight on my receiver, then tried to chamber the dummy round I made from the one piece of formed brass I made. The bolt handle seemed to get all the way forward and then stop before dropping. I had to unscrew the barrel about 70° to get it to close easily. That's about 0.010".

I didn't think I could be off that far so I hand tightened the barrel again, got out my Hornady modified case (for setting bullet seating depth) and it chambered just fine. Side by side they look near identical. I'm going to have to do some careful measuring to see what is different.

I also installed my 3/4-24 Sidewinder brake adapter on the muzzle.

Any way, I have the parts, now I need to make it in to a system so I can just grab the case, grab a range bag and go shooting a mile+.

After I get the brass sorted out and the barrel final torqued in the receiver I need to cut and mount the 15mm linear bearing bipod mount, drill the Arca rail adapter to bolt to the linear bearing, cut the Kaizen foam for my case to hold the rifle, bipod, magazines and ammo, develop a load at 200 yards, zero it, generate DOPE at probably 300, 600 and 1,000 yards and then take it somewhere that I can stretch it out.

 

[Buck Fever]

I got my 0.400" headspace comparator out and found the problem, it is about 0.013" longer than the Hornady modified case. I guess my presbyopia is getting the better of me, luckily my first prescription readers should be in my hands next Tuesday.

I'm going to see if I can bump it back another 0.009" and see if it closes so that I can nail the initial brass sizing and reduce the stretch on first firing.

Now a question, how much can a chamber move back when going from hand tight to 150 ft-lbs?

My rough calculation using bolt stretch calculators suggests possibly around 0.002" stretch but is that all behind the cartridge shoulder, leaving it relatively the same from a headspace perspective?

The 0.002" stretch also suggests about 14° of twist past hand tight to get to 150 ft-lbs torque.

 

[Buck Fever]

One good thing, initially I wanted to max out the barrel length at 32" but measuring it seemed like that might not fit in my case so I changed my order to 30". I'm glad I did because it's a very tight squeeze in my SKB 4909 case. To fit I have to remove the rear of my chassis (luckily I only have to loosen one set screw for that) and remove my Area 419 Sidewinder brake which is a self timing design and can be installed and removed by hand.

My scope is pushing the limits of the 9" width so I'm going to carve about 1/4" off the bottom of the pistol grip so that i can have more foam surrounding the sides for squish if the case gets dropped. That was excess length on the grip any way, it won't be missed unless someone with really big hands trys it.

 

[Savage 12BVSS]

It will move some as you tighten for sure, I usually mark the barrel with sharpy when its where I want it and you can then see how far it continues. Start to tighten before its where you want it for headspace, I like mine to tighten on brass right as bolt fully closes. Takes some trial and adjustment setting it perfect for headspace. Good Shooting

 

[shortgrass]

150# of torque on a barrel to receiver connection is completely not needed or necessary

 

[Buck Fever]

It's the spec ARC uses and it's nothing for a 1.0625"-20 thread. Why would I do any less?

 

[shortgrass]

Because 150# is not needed to secure a barrel to an action, that's why! 60# is plenty. But, it appears you will believe about about anything posted on the sites you visit. I didn't fall off the turnip truck yesterday. I've been fitting custom barrels for 30+yrs and I did bother to get a formal gunsmithing education, although it wasn't on the interdnet, it was a 2yr accredited school. I'm not a betting man, but I'd bet your barrel vise lets the barrel slip long before you reach your 150#. 60 Ft. pounds will hold the 2 together securely. 150 ft. pounds will do nothing but stretch threads more than need be. Its a "wanna-be" thread. You don't want any advice from those that "do", like sable tireur, or anyone else. Good luck . Pre-fit barrels are for the hobbyist crowd. Nuf said

 

[Buck Fever]

Yep, I'm a hobbyist with a prefit barrel and the guy suggesting 150 ft-lbs is the know-nothing who designed and manufactured the action.

 

[Savage 12BVSS]

30-50 ft lbs. is accepted as normal, some use less and a few go up to as high as 70. I snug in position and give two raps with a 2lb. hammer. Never had one get loose and have done more than a few...... pre fits work great and it don't take a gunsmith to install one on any of my savage's Go over to the savage forum and ask how many people pay for headspacing or taking their savage barrels on and off for them. If shooting twos and threes and being able to switch out your barrel's at your own discretion are for the hobbyist's crowd then count me in All savage barrels are threaded pre-fits and I trust Criterion or Lothar Walther will do a good job building the barrel, they do so for a living and never done me wrong.........

 

[Buck Fever]

Yes, I'm a fan of the Savage type barrel nut and also ARCs Barloc system (I have two currently) but I decided to go for a shouldered prefit on this one since it's a really long and heavy barrel (8.4 lbs) and potentially pushing the SAAMI spec on pressure. My first real "magnum" too.

I guess LW liked it because now they list American Rifle Company in their menu of barrel threads for their custom barrels. It wasn't there when I ordered and I had to send them the tenon blueprint.

So far the barrel looks nice on the outside and seems to headspace properly on the brass if the case shoulder is where it should be. I'm going to be doing a lot more measuring, inspection and test firing before I fully develop an opinion on the barrel but so far it is looking nice.

 

[atblis]

With an inside action wrench on a Rem 700, I wouldn't do 150 ft-lbs. That's probably where many people are coming from (R700 stuff).

Lilja did an interesting and most likely applicable to the 300 RUM experiment with barrel length. It appears 30" is likely the point of diminishing returns (arguably).

Barrel Lengths in the 338/378 Weatherby Magnum - Lilja

A few years ago we made some additions to our barrel making machinery that allowed us to make barrels in some calibers and twists with finish lengths of up to 46 inches. One of the first calibers we added in these extra-long barrels was the .338 and in a 10″ twist rate. During the initial...

riflebarrels.com

 

[Buck Fever]

For hunting, I agree with him.

Adding 2" and 36 fps probably would have been better for a heavy ELR rig but wouldn't fit my case.

30" will be ok but 34" or 36" probably isn't too long.

My situation is a bit different because 338 RUM is a lot smaller than a 338-378 Weatherby but it still is pretty big. One reason why i decided that 338 RUM was my chambering is that 338 Edge isn't necessarily always going to have a velocity advantage especially with the lighter 250 grain class bullets.

 

[Buck Fever]

I need a bushing for the Brownells barrel vise.

Instead of paying $30 and shipping for one set from Brownells, I think I'm going to buy a foot of 1.75" by 0.250" wall aluminum tube and have enough material to make 4 sets of bushings for $25 shipped.

I'll saw it to 3" length, then saw through one wall so it remains in one piece but can clamp down on my barrel.

If it works well, I'll sell the other three for $15 each shipped.