And So It Begins - .375 WSM Project

[Llama Bob]

After

After our exchange last year I thought for sure your were a died in the wool 7MM man! With its superior BC and all that?

The big change was Federal's release of the Edge TLR/Terminal Ascent with both incredible BCs and great terminal performance. They offered a heavy .308 and only a light .284. So for the time being the 7mm WSM is in the safe and the .300 WSM is up to bat. If the bullet situation changes again, it's possible I'll switch back. I certainly didn't sell my 7mm.

 

[LoonWulf]

The big change was Federal's release of the Edge TLR/Terminal Ascent with both incredible BCs and great terminal performance. They offered a heavy .308 and only a light .284. So for the time being the 7mm WSM is in the safe and the .300 WSM is up to bat. If the bullet situation changes again, it's possible I'll switch back. I certainly didn't sell my 7mm.

I just saw a bunch of those TLRs for sale on Midway I think for what I thought was a reasonable price I've got some of my cart but I never submitted the order Don't know if they're still there....

 

[Elkins45]

I bought my LH Ruger stainless laminated in 375 Ruger for $600 on close out from CDNN. When I bought it I picked up 200 rounds of brass, which is probably two lifetimes worth for me. I’m never going to knock a guy for wanting to build himself a bespoke gun, I’ve done it myself. But for the price difference I’m willing to carry an extra pound or two and risk the 0.00001% chance of a misfeed on a follow-up shot against a bear attack.

 

[LoonWulf]

Delete, wrong thread......

 

[Llama Bob]

I just saw a bunch of those TLRs for sale on Midway I think for what I thought was a reasonable price I've got some of my cart but I never submitted the order Don't know if they're still there....

The Edge TLR is dead or about to be. The Terminal Ascent is the replacement. Supposedly better accuracy and less pressure with the TAs. I have quite a few of both, but I wouldn't buy into the TLR at this point.

 

[Llama Bob]

Making some good progress. The rifle has arrived, and been fit with the Bell & Carlson stock and PTG Oberndorf bottom metal.



This B&C stock needed more fitting than the one on my .300 WSM, but it's acceptable. I also did a mockup on the .300 WSM to make sure that the combination of a 30mm scope, Talley QD low rings and bases, and NECG solder on safari sights will work. This ended up being a fairly complicated exercise, and the jury is still out. It looks like I can make it work, but it requires a high front sight and that may cause problems with what hood to use. I need to recheck my math in the morning, but it looks like the WSM guns must have a very steep taper in the barrel compared to most hunting rifles. I guess that makes sense - they have a magnum sporter shank and a pretty small muzzle. Or I just made a measurement or math mistake.

If their wait isn't insane, I'll probably use NECG to install the sights and reblue the gun. The local smith balked a bit and that's never a good sign.

I also made 51 pieces of brass with no losses, so I think I've got brass sizing down.

 

[LoonWulf]

Thats gonna an awsome rifle!

 

[troy fairweather]

Looks awesome, any chance to get a pic of the ptg bottom I don't think I've ever seen one on a rifle lol.
What was the Smith balking about with doing the sights, not much to it, should be sliver soldered on other wise if hot blued the sights will fall off.

A nice mate rust blue would look very nice for this build.

 

[horsemen61]

Can’t wait to see the bear stopper finished up!!!!

 

[Llama Bob]

Looks awesome, any chance to get a pic of the ptg bottom I don't think I've ever seen one on a rifle lol.

There's an action screw that needs replacing, but it looks like a pretty good fit overall. It snapped together with the B&C inlet and factory mag box without any trouble.

Anyone know a good source of Torx action screws for M70s?

What was the Smith balking about with doing the sights, not much to it, should be sliver soldered on other wise if hot blued the sights will fall off.

Not really sure. I think he didn't want to deal with the polish and bluing maybe? Soldering them does not look that hard - I may do it myself.

 

[Llama Bob]

I re-did the sight height math. I must have done something wrong last night, because when I worked it out longhand today for both the .300 WSM and .375 WSM, I got that the NECG sights at normal front sight height would both clear the bases and provide adequate ability to get the guns regulated. I'm much more comfortable with this answer, because this really isn't a special case - I checked the WSM barrel profile and it's very similar if not the same to the regular M70 short action sporter profile.



There is an argument here for going to a sight with only 1 folding leaf, or even no leaves. The MPBR zero I plan to regulate the fixed blade for reaches out to about 280y for the .300 and about 230y for the .375. Honestly I'd be reluctant to shoot much farther than that at game with an express type sight. A 400y leaf seems pretty optimistic. The leaves could be kind of fun at the range though.

With this out of the way I can buy a set of Talley bases and rings for it knowing that they should work with the sights OK.

 

[horsemen61]

This is so cool to me your somewhat making a custom rifle and I love it!

 

[troy fairweather]

I my get a set of old style Talley for my pre 64, I have a set of qd Talley rings but I need some parts I was going to call them and see if I can get them.
I like that bottom metal, the ptg always looked good and not to pricy. One of the action screws for my m70 is camed out so I'll get a new set soon don't know how makes the Allen key ones tho.

 

[Llama Bob]

This looks promising for action screws:

https://www.newenglandcustomgun.com/proddetail.php?prod=N-70B

I want to switch the .300 WSM over too - it's got standard screws, which work better than Phillips but only barely.

 

[amflyer]

Have you loaded some of the brass with bullets/no primer or powder and tried a function test yet?

 

[High Plains]

Llama Bob——This is a very, very interesting wildcat and I will follow it as closely as I can.

 

[Llama Bob]

Got the NECG action scews. They are a solid replacement for any older M70 with sketchy screws. The hex heads would be very hard to damage I think.

 

[horsemen61]

Got the NECG action scews. They are a solid replacement for any older M70 with sketchy screws. The hex heads would be very hard to damage I think.

View attachment 1003442

man that looks good!

 

[Llama Bob]

I also want to get a Lee factory crimp die for .375 WSM - I'm not 100% sure I'll use it, but since I may be using compressed loads I want to be able to clamp everything in place. A round that grows in length could lock up the action. Unfortunately Lee is not making custom dies right now.

As a cheap option, I bought an extra .325 WSM crimp die. I'm going to have the collet reamed out 0.05" and see if the resulting die is usable. If not, not a big loss...

 

[Llama Bob]

man that looks good!

I agree. This is a really easy platform to make progress on and the aftermarket parts have fit very well overall. While the New Haven classics probably aren't the best M70s off the shelf, the things that are wrong with them are easy to fix. The FN guns with the MOA trigger are nicer in a lot of ways, but the trigger is a no-go for me.

There are FN M70 WSM actions with the old trigger, but they were built for FN police rifles and I've never actually seen an action in person.

 

[Llama Bob]

Have you loaded some of the brass with bullets/no primer or powder and tried a function test yet?

As much as is possible given the gun still has a .270 WSM throat and bore, yes. I made both soft and solid dummies, and they feed from all three mag depths just fine. Very smoothly, actually.



The only functional problem I encountered (not with the dummies) was a slight hitch on bolt close. It felt like a tool mark or something. Working the action a few times made it go away - I'm not sure the rifle has ever been fired much if at all.

 

[Mk-211]

There was a thread on a rifle made in 8mm-378 Weatherby! Probably archived but you can search for it.

I don't think the poster ever shot it, might be a picture of it. Seems like it would be one heck of a bear stopper itself.

 

[Llama Bob]

There was a thread on a rifle made in 8mm-378 Weatherby! Probably archived but you can search for it.

I don't think the poster ever shot it, might be a picture of it. Seems like it would be one heck of a bear stopper itself.

I guess it's about the fastest 8mm you could make other than 8mm-338 Lapua maybe. It'd be a big heavy gun though. With that much case I'd think the factory .338-378 would be more appealing.

 

[troy fairweather]

I guess it's about the fastest 8mm you could make other than 8mm-338 Lapua maybe. It'd be a big heavy gun though. With that much case I'd think the factory .338-378 would be more appealing.

My dad built a 338-8mmremmag years ago, it was impressive with the newer high bc bullets one would be nice.

 

[Llama Bob]

My dad built a 338-8mmremmag years ago, it was impressive with the newer high bc bullets one would be nice.

Going that direction makes some sense to me. Not enough sense to tote around a magnum action medium bore, but at least I can see why someone would do it.